Water Quality Improvement Plan

Douglas Shire Far North Queensland

December 2006

Prepared by Douglas Shire Council, Far North Queensland Funds provided by Natural Heritage Trust, an Australian Government Initiative Compiled by Richard Davis, 2006

This publication may be cited as Richard Davis (2006): Douglas Shire Water Quality Improvement Plan. Douglas Shire Council

Executive Summary

Background 1. In late 2003 the Queensland and Australian Governments agreed to the Reef Water Quality Protection Plan (RWQPP), the objective of which is to halt and reverse the decline in water quality entering the Reef within 10 years. The RWQPP identifies nutrients and sediment as pollutants impacting on the inner reefs and seagrass areas of the Reef. Under the auspices of the RWQPP, Water Quality Improvement Plans (WQIPs) are being developed and implemented as the primary management vehicle for achieving long-term ecologically sustainable pollutant loads to Reef waters.

2. Douglas Shire was chosen for the initial WQIP and associated projects, which commenced prior to release of the RWQPP, because of (a) the willingness of the Douglas community to accept and adopt change to protect its environment, and (b) the relative small size of the Douglas catchments and therefore likelihood of demonstrating effective water quality management over a shorter period.

3. WQIPs, prepared through the NHT Coastal Catchments Initiative (CCI), are environmental management plans that codify and implement Australia’s National Water Quality Management Strategy (NWQMS) and the National Principles for the Provision of Water for Ecosystems.

4. This WQIP: • identifies current status of pollutant loads; • identifies the Environmental Values (EVs) of water bodies in Douglas Shire, and the Water Quality Objectives (WQOs) that will protect the EVs; and • commits to a set of management actions to achieve and maintain those EVs and WQOs, and which will take the first steps to reducing the current pollutant loads towards the achievement of sustainable pollutant loads. • derives estimates of pre-European and current loads of nutrients and sediments from Douglas Shire; • develops modelling and monitoring systems, and adaptive implementation strategies.

5. Implementation of the WQIP will require sustained partnerships between the Douglas Shire Council, FNQ NRM Ltd, relevant Queensland Government agencies, and industry bodies such as Canegrowers and Agforce (see Table 1)

6. The Wet Tropics NRM Board (FNQ NRM Ltd) has developed a natural resource management plan for the region under the NHT’s regional NRM programme. The Australian Government considers implementation of WQIPs a core deliverable of the regional NRM programme. Therefore the Douglas Shire WQIP will be integrated into the Wet Tropics NRM Plan and its implementation accorded a priority for investment under the regional NRM arrangements.

Environmental Values and Water Quality Objectives 1. Douglas Shire contains parts of two World Heritage Areas – the Wet Tropics and the Great Barrier Reef World Heritage Areas (WHAs). The Environmental Values (EVs) of the freshwaters, estuaries and near-shore waters of Douglas Shire have been established by the Queensland Government, through consultation with the Shire community. These have now been scheduled under an amendment to the Queensland Environmental Protection (Water) Policy 1997. The EVs are the waterway values and uses to be protected for these areas. A census conducted by CSIRO found widespread community support for retention of the natural values of the Shire’s waterways.

2. Total suspended sediments (TSS), and the nutrients - total nitrogen (TN) and total phosphorus (TP) are the three parameters of concern in this WQIP. Water Quality Objectives (WQOs) were established for these parameters to protect the EVs. Subsequent work by QEPA has expanded the WQOs to other parameters and to the whole Shire. These added parameters and waterways have not been included in this plan.

3. Comparison of the WQOs with an ambient water quality monitoring program showed that water quality in the Daintree River and the upper Mossman River meets the water quality objectives for all pollutants of concern. Forms of nitrogen exceed the WQOs in the lower reaches of the Mossman River, while phosphate exceeds the WQO in the lowest reach of the Mossman River and Cassowary Creek. The turbidity WQO is also exceeded in Cassowary Creek. Lower Mowbray exceeded turbidity, total nitrogen and phosphorous.

4. The principal point sources of the three parameters of concern in this WQIP in the Shire include the sewerage treatment plant at Mossman, unsewered residential areas, tourist resorts, boat discharges (polluter can be isolated, but discharge is diffuse) and aquaculture. Principal diffuse sources include nitrogen losses from sugarcane production, sediment loss from shire’s modified drainage pattern, and streambank erosion.

5. There has been no long-term monitoring suitable for calculating pollutant loads, (the amount of pollutant eg suspended solids delivered over a period of time). Using CSIRO modelling and expert opinion, TSS, TN and TP loads are estimated to be 134,000 tonnes, 2,250 tonnes and 179 tonnes per annum. Uncleared land, principally in the WHA, is by far the major source of all three pollutants due to the dominant share in area within the catchments.

6. The same models were used to calculate pre-European settlement loads as 72,800, 1,980 and 122 tonnes p.a. for TSS, TN and TP respectively. These values are used as the interim long-term Aspirational targets for the WQIP. These values will be reviewed with further information generated during the 7-year life of the WQIP.

Pollutant Loads 1. Sugar cane is the principal crop grown in the Shire. There is some beef grazing in the mid- Daintree catchment and small pockets within the other catchments. Tourism, based on the two WHAs, is a major activity in the Shire with Port Douglas the centre of this activity.

2. The principal point sources of nutrients in the Shire include the sewerage treatment plant at Mossman, unsewered residential areas and tourist resorts, boat discharges and aquaculture.

3. Principal diffuse sources include nutrient and sediment losses from sugarcane production, cattle grazing, and streambank erosion. There has been no long-term monitoring suitable for measuring current pollutant loads. Using CSIRO modelling, TSS, TN and TP loads are estimated to be 134,000 tonnes, 2,258 tonnes and 179 tonnes per annum respectively. Land which is relatively undisturbed, principally in the World Heritage Area, is by far the major contributor to all three pollutants, due to its much higher area than other land uses. Further water monitoring data inputted into the modelling will improve these estimates.

4. Pre-European settlement loads of TSS, TN and TP are estimated from modelling to have been 73,000 tonnes, 1,980 tonnes, and 122 tonnes per annum respectively. These values are used as long term aspirational targets for the WQIP, as it is believed that achievement of these targets will protect the EVs of the Great Barrier Reef. These values equate to a reduction of 45% for TSS, 12% for TN, and 32% for TP. However, there are very high uncertainties associated with these modelled pre-European and current day loads. These uncertainties will be addressed through this WQIP’s adaptive management strategy.

5. In the absence of precise information on impacts of land based pollution from Douglas Shire on the Reef, it is proposed to set a 25 year load reduction target of half the Aspirational targets; that is, 22.5% reduction of TSS, 6% of TN and 16% of TP for protection of the GBR. These targets are effectively Resource Condition Targets (RCTs), and equate to half the anthropogenic (human-induced) loads of these pollutants. Both the Aspirational and Resource Condition Targets will be reviewed during the life of this WQIP.

Environmental Flows 1. Aquatic life in the rivers and estuaries of Douglas Shire depends on the continuation of long term flow patterns as well as good water quality. Flow patterns can be modified through barriers across rivers; extractions of water; discharges of water; changes in land use; and climate change.

2. There are no barriers across Shire rivers, with none planned. There are some small irrigation and town water supply abstractions under licence to the Queensland Department of Natural Resources and Water. The abstractions may have local effects; water supply to Mossman and Port Douglas does not constitute a major component of river flows.

3. There have been major changes to land use, altering runoff patterns in the lowlands. Although there are no monitoring data available, runoff is believed to have become more immediate as a result of vegetation clearance, drainage works and wetland reclamation. The CSIRO modelling shows that 87% of runoff originates in the high rainfall coastal ranges where vegetation is relatively undisturbed.

4. The volumes and patterns of flows in the rivers are not believed to have changed significantly since pre-European times, although there may be some changes in the immediacy of runoff in the lowlands as a result of land use change.

5. The Douglas Shire Council and the Queensland Department of Natural Resources and Water have drafted an MoU containing draft flow objectives. This Plan recommends the following objectives, consistent with the MoU: • Maintain current flow volumes; • Maintain inter-annual and intra-annual natural flow variability; • Prevent barriers to wetland and floodplain inundation; • Minimise effects of weirs and other barriers across rivers; • Minimise effects of dams on water flows; • Minimise drainage to rivers and estuaries through BMPs and recycling; • Minimise water withdrawals from rivers; and • Maintain in-stream river and estuarine physical habitats.

Pollutant Management Actions A range of actions to reduce pollutant losses from point and diffuse sources was identified through consultations with stakeholders and scientific investigations. Table 1 provides a concise listing of actions required over set times. The table also indicates the lead agencies involved with actions. While some of the actions carry commitments, others have as yet attracted no or insufficient commitments to ensure they are undertaken. During the life of the Plan, and using the principle of adaptive implementation, opportunities will be explored to maximise the implementation of all actions. It is also likely that the RWQPP will result in opportunities for implementation which can be exported into low and medium priority catchments, such as the Mossman and Daintree Catchments.

Table A: Priority management actions determined that will reduce nutrient and sediment loads entering the GBR lagoon for Douglas Shire # MANAGEMENT ACTIONS1 Start Finish Estimated2 Lead Agencies 3 Partnership Costs Linkage Licensed/regulated sources and activities 1 Upgrade Mossman STP (Section 4.1.1). 2007 2013 $5-6M DSC NRW, DLGPS, QEPA 2 Connect Newell & Cooya Beaches septic systems to Mossman 2008 2013 $10-13M DSC NRW, DLGPS STP. Connect Wonga Beach to Mossman STP or a stand-alone system (Section 4.1.7). 3 Ensure all tourist boat effluent is discharged to the Port Douglas 2010 Ongoing $10K/vessel Queensland Marine tour land-based repository for treatment. (Section 4.1.3) Transport (QT) operators, DSC 4 Ensure aquaculture discharges work towards achieving WQOs 2008 Ongoing QEPA Aquaculture for adjacent watercourse reach. (Section 4.1.2) industry 5 Investigate area in the Shire where there needs to be a Ongoing $3-5M DSC Community, prioritised replacement of rural residential septic systems. (Section 4.1.7) 5.1 Identify alternative waste disposal systems. Provide Ongoing $20K DSC information on replacement toilet systems. Establish pump-out database for compliance measures. 6 Ensure river tour operators comply with speed limits. (section Ongoing $10-12K/yr QT River tour 4.1.3) operators, DSC 6.1 Identify boat design options to reduce wave wake. Provide 2008 2013 $30K QT DSC & tour boat information to operators on objectives to maintain speed limits. operators Introduce design requirements for new operators/boats.

1 For details see sections 4.1 and 4.2./ 2 Costs are indicative to the inkind and cash contribution required to implement the action 3 This column identifies the agencies that can lead discussion to the action, but not necessarily contribute the full cost, nor at this stage commits them to undertake the actions described.

7 Amend permits for quarries under 5,000m3 to ensure Ongoing $5K/5yr DSC compliance with the Environmental Protection (Water) Policy, 1997. (Section 4.1.4). 7.1 Undertake awareness program via site visits and inspections, Ongoing $3K/yr DSC Extraction prior to and during wet season, and distribution of guidelines. Industry 8 Maintain & review license conditions on quarries over 5,000m. Ongoing QEPA Extraction (section 4.1.4) Industry 9 Water-take and management of legal entitlements Ongoing Not determined NRW 9.1 Introduction of metering surface & groundwater 2012 2013 Not determined NRW extraction(excluding domestic supply) 9.2 Develop a Wet Tropics Water Resources Plan 2008 2011 Not determined NRW Community Urban stormwater 10 Implement Erosion Control & Stormwater Management Ongoing DSC Development Development Guidelines. (Sections 4.1.5 and 4.1.6) Industry 10.1 Ensure all building contractors have, and adhere to, erosion 2007 Ongoing $5-10K/yr DSC control methods. Undertake site inspections prior & during wet season. Implement penalties system for non-compliance under the EP(Water)P. 10.2 Investigate sediment prevention and settlement plus nutrient 2008 2009 $30K (does not DSC EPA (guidance removal or redistribution for the wet tropics. Survey urban include for DSC), runoff/erosion and recommend priority sites for remediation, installation) DPI&F (possible including installation of retention/settlement ponds. role associated with wetlands and marine plants) 10.3 Enhance stormwater management and compliance to ensure 2006 2013 Incl 9.1 & 9.2 DSC Development consistency with the Environmental Protection (Water) Policy, Industry 1997. Implement community awareness program. 11 Implement relevant State Government guidelines on reducing Ongoing Incl in above DSC FNQROC, domestic pollutants. (section 4.1.7) NRW, QEPA Cane-growing: fertiliser management 12 Make slow-release fertiliser available to cane growers. (Section 2006 2008 4 Cane industry NHT, Joint 4.2.1) groups, QFF, Steering

4 It is proposed these be pursued as a reef catchment-wide initiative, and therefore supported through implementation of the RWQPP. Committee (disbursing funds), DPI&F, BSES, FIFA 13 Develop and implement the Douglas Shire Fertiliser 2006 Ongoing $20K for DPI&F, FNQNRM DAFF, DSC Management Strategy for the purpose of achieving the development Ltd. Cane industry WQIP’s objectives. (Sections 4.2.1 and 4.2.2) only groups 13.1 Identify barriers and incentives for uptake of alternative cane 2006 2007 Other WQIPs are DAFF, FNQ NRM, Cane industry & growing/fertilising techniques. Implement incentive for continuing this CSIRO research groups, action, commenced improved fertiliser/land management, recognising the private in the Douglas, DPI&F benefits of implementation. with work undertaken by CSIRO 13.2 Implement the Douglas Shire Fertiliser Management Strategy 2007 2013 Cane industry DAFF, NHT, to assess the effectiveness of alterative fertiliser use practices. groups (Extension DPI&F Establish trial sites throughout the Shire where N fertiliser is $150K for 3 yr Component), BSES, applied: trials CSIRO (Research - consistent with recommendations following soil and/or Component), FNQ plant tissue analysis; NRM - sub-surface and as soluble/slow release forms; - optimal with respect to timing of application and application methodology; and - at reduced rates to assess any production losses due to reduced application rates; for comparison to conventional fertiliser use practice. The Strategy will also: $30K - trial legume crops &/or soya hybrids under varying paddock conditions; - promote case studies of successful drilling of legume into trash, eg Sugar Awareness Day; - investigate commercial pricing of mill mud mix; - evaluate the results of case studies with long history of analysis on fertilizer variation; and - investigate the N/yield relations of low N requiring varieties of cane. 13.3 Implement the Douglas Shire Fertiliser Management Strategy, 2006 Ongoing $180K over 3 Cane industry Research groups, through working with canegrowers in Douglas Shire to ensure yrs groups. Linkage FNQ NRM Ltd, , that fertiliser use and applications are consistent with through DPI&F DAFF, DPI&F, achievement of this WQIP’s objectives, and to this end are: Future CaneInitiative FIFA, Fertiliser - based on soil and plant analysis information; Industry - optimal with respect to timing of application and application methodology; - applied below a green trash blanket; - made sub-surface to avoid stormwater runoff losses; and - with slow release forms of fertiliser. The Strategy will also facilitate the use of fallow system and, low N or N-fixing cane varieties. 13.4 Develop effective techniques to direct drill into trash and for 2006 2009 $30K Cane industry & DPI&F, DAFF trash planting. research groups

13.5 Develop and make available information for canegrowers and 2007 Ongoing Cost Cane industry & FNQ NRM Ltd, related service industries on (a) the costs and benefits of non- incorporated research groups DPI&F, DAFF conventional fertiliser practices, (b) losses from different N into above tasks sources, (c) legume fallow cropping, (d) both costs and yield effects of fertilizer applications based on regular soil analyses, and (e) use of low N requiring cane varieties. 13.6 Provide soil testing service to determine plant requirements Incl in 12.3 Cane industry groups DPI&F other than N, which has taken into account mill mud and fallow legume. Cane growing: drain and wetland rehabilitation 14 Develop and implement a Douglas Shire Cane Drain 2006 Ongoing $20K for Cane industry NHT, NRW, Management Strategy, which is designed to modify drains in development groups, FNQ NRM DSC, Joint cane growing properties to achieve the WQIP’s objectives. only Ltd, Steering (Section 4.2.3) Committee (setting funding priorities), DPI&F 14.1 Establish a working group that includes Douglas Shire 2006 2007 FNQ NRM Ltd Cane industry Council, landholders and Main Roads to develop the proposed groups, DSC, Cane Drain Management Strategy. DPI&F, DMR, NHT 14.2 Develop the proposed Douglas Shire Cane Drain Management 2006 2008 $150K FNQ NRM Ltd Cane industry Strategy that will: groups, DPI&F, - identify drains in the Shire and the relative risk of sediment DSC, DMR, and nutrient loads to the Reef; NRW, NHT - identify existing wetlands and their condition, and opportunities to construct wetlands to optimise the capture of pollutant loads and improve wetland functionality; - identify and develop drain rehabilitation measures for the Shire (including an evaluation of local application/modification of detailed recommendations from Herbert/Johnstone catchments); and - rank drain and wetland rehabilitation works according to cost-effective water quality outcomes; - cost-sharing options for deep drain design and stabilisation. 14.3 Implement the Douglas Shire Cane Drain Management 2008 Ongoing $100K/yr Cane industry NHT, DPI&F, Strategy. Implementation will include: groups, FNQ NRM DSC, DMR - field days to demonstrate stable drains; Ltd, - photo sets and procedures on drain and wetland rehabilitation; - the promotion of wetland values in the shire; and - a funded program of prioritised works. Grazing management 15 Develop and implement a Douglas Shire Grazing Management 2006 Ongoing $20K DPI&F, Grazing Strategy. This will be achieved by maintaining dense industry groups, FNQ groundcover for slopes and plains through implementing Farm NRM Ltd Management Systems and GRAZING. (Section 4.2.4) 15.1 Establish a grazing study group. Determine soil losses from 2007 2009 $100K Grazing industry & FNQ NRM Ltd, hillslope erosion. Initiate research of vegetation type and research groups DPI&F management on runoff/erosion. Produce research model using published runoff data from comparable cover/slope situations. Investigate burning season effect on soil loss. Incorporate findings into Douglas Shire’s SedNet. Undertake survey of locations where productivity and stability currently occurs. Identify existing legal duty of care by graziers as a baseline to determining cost-share arrangements. 15.2 Undertake a series of field days involving land management 2007 Ongoing $50K DPI&F, Grazing FNQ NRM Ltd, decision makers, including landholders, DPI&F, NRW, NRM industry & research NRM Board Pty Ltd and downstream stakeholders. Establish trials to groups compare current practice with spring burning (moist soil) and herbicides for regrowth. Produce graphic examples and descriptions of grazing condition classes for landholder field evaluation. Promote field days and invite cooperation to trial alternative burning regimes. Establish soil loss plots on grassland and forest slopes. Horticulture and Forestry 16 Land managers adopt priority BMPs in all horticultural crops 2006 Ongoing $20K DPI&F, FNQ NRM Ltd, consistent with Farmcare. Undertake extension programme to GROWCOM, HAL NRM&W. maximise adoption of priority BMPs through short courses and or equivalent. demonstrations. Facilitate incentive programs aiding landholders in the implementation of priority BMPs. (Section 4.2.7) 17 Ensure adoption of CoP for forest activities on private lands. 2006 Ongoing $20K Forestry industry & DPI&F, DSC Investigate suitable forest species for a range of situations in research groups, (planning codes) this shire. Extension service that provides sustainable FNQ NRM Ltd techniques in establishment, silviculture, harvesting. (Section 4.2.9) Improved knowledge and science support for decision-making 18 Enhance receiving water quality model(s) 2006 2009 $50K Reef Water Quality CSIRO, DSC, Partnership NRW, DEH 19 Ambient water quality monitoring for improved model Ongoing $15K Reef Water Quality Community, calibration/verification. Partnership Mossman Monitoring Alliance (FNQNRM Ltd, DEH, CSIRO, NRW, EPA, GBRMPA, DSC) 20 Maintain and enhance predictive models and decision-support Ongoing $50K Reef Water Quality CSIRO L&W, tools (SedNet and EMSS). Partnership NRW, FNQ NRM Ltd, DEH 21 Provide science support for adaptive planning purposes and Ongoing $20K Reef Water Quality DEH decision-making. Partnership Riparian management 22 Reduce and avoid further river and creek bank erosion, through 2006 Ongoing $100K/yr River Improvement NHT, NRW stock exclusion, establishing off-stream watering points and Trust, DSC (regulatory role), stable on-stream watering points, and vegetative and QEPA mechanical bank stabilisation. Support coordination and (regulatory role, implementation of on-ground works. (Sections 4.2.5 and 4.2.6) DPI&F (regulatory role – marine plants) 22.1 Map erosion risk areas and determine erosion rate at active 2007 2008 $50K River Improvement NRW sites. Identify and recommend stabilisation methods for each Trust, DSC risk class. Investigate and evaluate incentives options. Produce guide that analyses costs and benefits for appropriate management of watercourses and explains incentives and landowner obligations. Investigate cost-effectiveness of locally adapted stabilisation techniques, building on outcomes of the DSWQIP plus from the Tully & Johnstone. Review landholder riparian agreements as circulated September 2004. 22.2 Conduct field trips within Douglas and to other Shires to 2007 Ongoing $5K/2yr River Improvement NRW demonstrate successful erosion mitigation, including off-stream Trust, DSC watering point demonstration sites. Undertake a series of field days involving land management decision makers, including landholders, DPI, DSC, DNW, EPA, NRM Board Pty Ltd and downstream stakeholders. Use existing videos on riparian rehabilitation to promote uptake to landholders. Remove or realign snags. Road maintenance 23 Develop and support implementation of road sediment action 2006 Ongoing $100K/yr DMR, DSC program for each sub-catchment as defined in the FNQROC Development Manual (current edition). (Section 4.2.8) 23.1 Develop rapid assessment method of identifying road sediment 2007 2007 $50K DMR, DSC sources and corrective action. Map and prioritise roads for sealing based on likely sediment loss to watercourses. Develop Shire road sediment control plan in consultation with landholders, including development controls. 23.2 Promote road drain management plans and engineering 2007 Ongoing $50K DSC WTMA, DMR guidelines to achieve drainage and soil stabilisation outcomes, including for steep roads. Recommend locations for application of techniques in Main Roads sediment control guidebook. Circulate leaflet to affected landholders on erosion control techniques, landowner obligations and cost-sharing (where available). Survey eroding steep private roads and promote engineering guidelines and landowner obligations. Monitoring 24 Implement, review and expand Douglas Shire Monitoring Strategy 24.1 Continue a load focused water monitoring program that, maintains 05/06 07/08 $90K/yr Mossman Monitoring ACTFR present estuarine modelling, provision of expertise to interpret Alliance, Reef Water data, inform community of findings to date, maintain automatic Quality Partnership sampling stations, provide adequate resources for collection, handling and analysis of samples. Update conceptual models 24.2 Undertake effectiveness monitoring such as, but not exclusively to, Ongoing Not determined Reef Water Quality ACTFR provision of expertise to interpret data from N-loss trial, determine Partnership effectiveness on drain remediation, & trial effectiveness of varying width riparian vegetation.

Reporting on outcomes from implementing the WQIP 25 Provision of annual, mid-term and final report that provides 2007 2013 $3K/yr DSC, FNQNRM Ltd, DEH information to the community and the State & Commonwealth Governments. Ideally the reporting structure need to be in one format that meet all constituents requirements

1. These were assessed against both effectiveness in reducing pollutant loads and acceptability within the Shire. Effectiveness was directly estimated for point source management actions, and obtained from CSIRO modelling for diffuse source actions. Acceptability was obtained from a survey of Shire residents and from consultations with industry groups.

2. The most cost-effective means of reducing sediment losses to the Reef lagoon is to stabilise and repair cane drains.

3. The most effective management action for reducing nitrogen loads is to reduce losses from sugar cane fields; however this action will need to be combined with other nitrogen reduction actions to have a significant effect on the Reef. Managing N loss is to be achieved through the consistent and reliable improvement in cane farm management, which includes; • application of fertilisers according to soil and plant tissue tests; • applying fertiliser sub-surface; • using slow-release fertiliser; • improved fallow management, and planting of leguminous crops (subject to further investigations); and • repairing two thirds of the cane drains to reduce sediment and nutrient loss.

4. Upgrades to Mossman STP, including connection of outlying villages, will contribute an 8% reduction in TP loads within 7 years. Improvements in cane drains will also reduce TP loads over the longer term.

5. It is proposed to achieve during the life of this WQIP a significant reduction in pollutant loads to the Barrier Reef lagoon: • A 12% reduction in the total sediment load (Aspirational target 45%; RCT 22.5%); • A 4% reduction in TN load (Aspirational target 12%; RCT 6%); and • A 14% reduction in TP load (Aspirational target 32%, RCT 16%). Loads of each of the three pollutants will be reduced by about half that needed to reach the Aspirational targets – if all management actions proposed are implemented over 25 years.

6. Management actions were categorized into Immediate (i.e. during the life of this WQIP), Support or Long-Term depending on their joint acceptability and effectiveness. Immediate actions included: • upgrading Mossman STP and commissioning Wonga Beach STP; • connecting villages to an STP; • implementing nutrient loss reduction practices in sugar cane production; and • converting shallow drains in sugar cane fields to grassed swales.

Monitoring and Research 1. A monitoring alliance developed in 2005 ensures collection of water samples from automatic water samplers in the Mossman Catchment, plus the 2 samplers in-paddock in a trial looking at effectiveness of reduced N-application for the 2005/2006 wet season. At present no community monitoring is being undertaken.

2. Water quality monitoring is required to improve management. This is achieved through determining (in order of priority): • the effectiveness of management actions; and • better estimates of current pollutant loads. • Improvements in the capacity of resource managers to use and refine predictive modelling

3. Quantifying the effectiveness of management actions and the rates of implementation by land managers will allow the plan to be modified as it is implemented. For example if the effectiveness of management action priorities is shown to be less than anticipated, other measures may need to be adopted or accorded greater priority. If the rates of management action uptake fall short of acceptable targets governments may pursue further incentives to enhance uptake.

4. It is proposed that the Decision Support System (containing the two water quality models used in preparation of this plan) be operated and improved over time by the Wet Tropics NRM Board.

5. High priorities for further scientific investigation include determining: • cost effective options for deep drain stabilization; • cost effective options for converting shallow drains into spoon drains; • the cost-effectiveness of cane fertilizer management strategies; • the cost-effectiveness of leguminous fallow plants; and • rates of stream bank erosion at active sites. These will be incorporated into the proposed monitoring programme.

Adaptive Implementation 1. The Plan will be implemented by Douglas Shire Council in collaboration with the Far North Queensland NRM ltd, State government agencies and industry groups, including individual land managers. Funding will be sought from federal-State programmes such as NHT2, as well as from State government sources.

2. To oversee the implementation of the WQIP (Tables 1 and 2) a local reference group will be formed with a direct link to the FNQ NRM Ltd.

3. There are currently known commitments for a limited number of the priority implementation, monitoring, and research activities. Funded priorities include: • upgrades to sewage treatment and connection of unsewered villages (Douglas Shire Council); • continuing sugar cane nutrient loss management trials for one year (CSIRO); and • a Monitoring Alliance between Local, State, Federal & Wet Tropic NRM Board ensures a 2005/06 wet season monitoring program

4. Notable unfunded priority activities include: • sugar cane nutrient reduction activities beyond 2005/06; • sugar cane shallow drain improvements; and • monitoring effectiveness of management actions, including drain stabilization techniques.

Reporting and Reviewing 1. Annual reports will be produced as part of the adaptive management approach, describing progress in plan implementation, results of monitoring and research activities, consultations with stakeholders and the public, actions of government agencies and any exogenous changes affecting Shire water quality. The annual reports will be provided for public inspection and comment.

2. The WQIP will be reviewed annually based on the annual reports, information from monitoring and evaluation of current and future management activities, and feedback from stakeholders and the public. These reviews will recommend changes in the plan implementation, if warranted, based on this information so as to maximise opportunities to more quickly and efficiently achieve the Resource Condition Targets These changes may include changes in the implementation of the management actions, and adoption of new management actions.

3. There will be a major review after 7 years to assess progress in meeting the load reduction targets, the effectiveness of the management actions and the appropriateness of the current load targets. A revised plan will be drawn up as a result of this review.

4. The considerable uncertainty in these loads because of untested assumptions in the EMSS and SedNet models means that these target values should be modified during the life of the WQIP as better information becomes available from a monitoring program and from advances in modelling in wet tropical areas.

Table B: Commitments to WQIP implementation. Task Accountability Period Budget Estimate and Contributions Action Implementation WQIP DSC 2005-06 Partnership funding for Implementation Officer ($40,000). Implementation Governments1 2005-07 Partnership funding for Implementation Officer ($60,000). Upgrade Mossman DSC 2006-11 Upgrade sewage treatment to tertiary level, $5-6M. STP Connect villages to 2006-11 Connect Newell & Cooya Beach to Mossman STP, $6-8M STP (40% State Treasury contribution to a component of above budget) Connect Wonga 2007-11 Upgrade present septic systems to STP Beach to STP $4-5M if connected to Mossman STP; $6-7M if reticulated in Wonga Stormwater DSC ongoing Council to ensure stormwater from new developments, building sites and extractive management industries (under DSC Extractive Permit) meets DSC Erosion Control and Stormwater Management Manual, through consultation & compliance. $15,000. 2005-11 Construction and maintenance of Shire’s drainage network, applying Best Management Practice in drainage management ($450,000) Road management DSC 2005-11 Council road sealing program $200,000. Conversion of verges/aprons for slashing access. $50,000. QDMR 2005-11 Main road maintenance of verges. Budget estimates not available. Sustainability Officer DSC 2005-06 Capacity building within DSC for sustainable management within Council, plus contribution to Greenglobe & Cities for Climate Programs, $35-45,000/annum, plus oncosts Wetland and riparian DNR&W, DSC. 2005-06 Undertake works as identified in WQIP (Project 4) as per River Improvement Trust restoration works schedule, $100,000. Governments1 & 2005-06 Rehabilitate wetlands, $200,000 (funding pending). DSC DSC 2005-06 Operation of Plant Nursery & planting team, $110,000. Governments1 2005-08 Assistance for plant propagation for peri urban plantings, riparian, drainage & wetlands (under the program revegetation for Community & Climate Program, $50,000. Extension – sugar QDPI Ongoing Extension services, including monitoring BMP uptake, $30-40,000. Extension – cocoa Ongoing Extension services in the establishment of alternative sustainable cocoa plantations. $7,000. Extension – grazing QDPI 2005–06 Provision of Grazing Land Management Package. $20,000. Monitoring Current pollutant QDNR&W 2005/06 Hydrographer, data collection and analysis, 2 automatic water quality sampling load monitoring stations ($25,000). QEPA 2005/06 Water quality sample analysis from 2 stations (Supply Acoustic Doppler equipment, $10,000. QEPA - $10,000). DSC 2005/06 Maintenance of 4 automatic water quality sampling stations ($8,000). DEH 2005/06 Cash contribution to a multi-agency Monitoring Alliance ($50,000). CSIRO 2005/06 Estuarine modelling program for the Mossman Catchment (up to $50,000). BMP monitoring QDPI, Ongoing See Extension – Sugar, Cocoa & Grazing. Governments1 Knowledge Acquisition Sugarcane nutrient CSIRO-CSE 2005/06 Collection and analysis from automatic water quality sampling stations, including reduction trials lysimeter analysis ($10,000). Sugarcane Nitrogen 2005/06 This research project is undertaken in the wet tropics including DS. ($50,000 CSIRO application inkind). Reporting/review Annual Review DSC/Governments1 Annual A role of the DSC Implementation Officer (approximately $3,000/yr) Mid & Full-term 2008 & Costing not available Reviews 2011 1 denotes delivery of Qld and Australian Government contributions through FNQ NRM Ltd.

Table C: Implementation Schedule for WQIP.

2005/06 2006/07 2007/08 2008/09 2009/2010 2010/2011 2011/2012 Action Implemetation (Immediate Actions only) Upgrade Mossman STP Connect Cooya, Newell & Craiglie to STP Provide an STP connection for Wonga Beach residents Reduce nutrient losses from sugar cane fields Rehabilitate shallow drains in sugar cane fields Extension of BMPs within the sugar industry1,2 Extension of BMPs within the cattle industry1,2 Extension of BMPs within the cocoa tree crop1,2,3

Monitoring Management Action effectiveness Current pollutant loads Monitoring 'input' information on management actions

Research (Priority research) Trial deep drain stabilization Trial cost effective options for shallow drains Field trials of sugar cane fertilizer management Economic research linking water quality with marine benefits

Reporting and Review Annual report 7-year report Annual review 7-year review 1 Commitment can be only identified for set period due to non-guarantee of resource allocation 2 While BMP delivery may not have a focus on water quality, a significant number of BMPs (including business planning have both direct and indirect benefit to water quality 3 A potentially alternative/supplementary tree crop in this shire CONTENTS

Executive Summary...... 1 Acknowledgements...... 25 Chapter 1. Introduction ...... 26 1.1 Background to the WQIP...... 26 1.1.1 Great Barrier Reef Water Quality Action Plan...... 26 1.1.2 The Great Barrier Reef Water Quality Protection Plan ...... 27 1.1.3 The Coastal Catchments Initiative...... 28 1.1.4 Wet Tropics Natural Resource Management Plan...... 30 1.2 Douglas Shire...... 31 1.2.1 Physical characteristics...... 31 1.2.2 Activities ...... 33 1.2.3 Geography of Douglas Shire ...... 34 1.2.4 Study Catchments of Douglas Shire...... 37 1.2.5 The Economy...... 43 Chapter 2 Environmental Values and Water Quality Objectives ...... 45 2.1 Environmental Values ...... 46 2.2 Water Quality Objectives...... 48 2.3 Pollutants of Concern ...... 50 2.3.1 Sectoral and Community Attitudes to EVs...... 51 2.3.2 Comparison of Current Water Quality and the WQOs...... 52 2.3.3 Existing programs addressing pollutants in Douglas Shire ...... 52 2.4 Pollutant Loads ...... 54 2.4.1 Point Sources of Pollution ...... 54 2.4.2 Diffuse sources ...... 57 2.4.3 Current Pollutant Loads...... 58 2.4.4 Loads from Monitoring ...... 58 2.4.5 Loads from Modelling...... 59 2.4.6 Seasonal variation in loads ...... 63 2.5 Pre-1850 Pollutant Loads ...... 63 2.5.1 Total Maximum Pollutant Load Targets...... 65 Chapter 3 River Flow Objectives...... 66 3.1 Environmental Water Needs...... 67 3.1.1 Role of flows ...... 67 3.1.2 Development Effects on Flow ...... 69 3.1.3 Modifications to Flow ...... 69 3.1.4 Environmental Flow Programs...... 71 3.2 Flow Management Objectives...... 72 Chapter 4. Management Actions...... 73 4.1 Point Source Management Action ...... 75 4.1.1 Mossman Sewage Treatment Plant...... 75 4.1.2 Aquaculture...... 75 4.1.3 Tourist Boats...... 76

20 4.1.4 Quarrying...... 77 4.1.5 Stormwater...... 77 4.1.6 Development Sites...... 77 4.1.7 Septic – Residential...... 77 4.2 Diffuse Source Management Action ...... 77 4.2.1 Reducing nutrient losses – Sugar cane...... 78 4.2.2 Fallow – Sugar cane ...... 78 4.2.3 Drain management – Sugar cane ...... 78 4.2.4 Ground cover – Grazing ...... 79 4.2.5 Riparian management – Cassowary Creek (Mossman Catchment)...... 79 4.2.6 Riparian management – Rest of Shire ...... 80 4.2.7 Fertilizer and soil management – Horticulture ...... 80 4.2.8 Sediment management – Roads...... 80 4.2.9 Reduced soil and nutrient losses - Forestry ...... 81 4.2.10 Feral Pig Management...... 81 4.3 Criteria for Assessment ...... 81 4.4 Cost Benefit Analysis ...... 82 4.5 Consultation...... 83 4.6 Land Use Change ...... 84 4.7 Changes in Pollutant Loads...... 85 4.7.1 Pollutant Load Reductions...... 86 4.8 Categorizing Management Actions...... 89 4.9 Management Actions for Implementation ...... 94 4.9.1 Adaptive Management Strategy ...... 104 4.9.2 Relationship between the WQIP and the RWQPP ...... 105 4.9.3 Relationship between the WQIP and the regional NRM plan...... 105 Chapter 5: Monitoring and Research ...... 107 5.1 Existing Monitoring Programs ...... 107 5.1.1 Mossman Monitoring Alliance...... 107 5.1.2 Queensland Government ...... 108 5.1.3 Monitoring During the WQIP Preparation ...... 109 5.2 The Water Quality Monitoring Program...... 110 5.2.1 Effectiveness of Management Actions ...... 110 5.2.2 Measuring Pollutant Loads...... 111 5.2.3 Calibrating the Water Quality models ...... 112 5.2.4 Input Monitoring ...... 112 5.2.5 Decision Support System...... 113 5.2.6 Monitoring for WQIP Review...... 114 5.3 Knowledge Requirements...... 114 5.4 Reef Water Quality Partnership...... Error! Bookmark not defined. Chapter 6: Adaptive Implementation...... 117 Chapter 7: WQIP Reporting and Review...... 123 7.1 Reporting ...... 123 7.2 Review of WQIP...... 124 7.2.1 Annual reviews...... 124

21 7.2.2 Mid-term review...... 124 7.2.3 Full Review ...... 125 References...... 127 Appendix A Environmental Values and Water Quality Objectives for Douglas Shire Waterways...... 129 Appendix B. Water Quality Models ...... 135 B.1 Comparison of the rainfall periods considered by EMSS and SedNet ...... 136 B.2 - Rainfall runoff calibration of EMSS ...... 137 B.3 – Pollutant parameters used in EMSS and SedNet ...... 142 B.4 – Implementation of Management Actions ...... 143 B.5 Results...... 146 Appendix C. Milestone activities undertaken in projects supporting the DSWQIP process (Activity reports can be viewed at www.dsc.qld.gov.au/)...... 151 Project 1: Adoption of Agricultural Best Management Practice for Sediment and Nutrient Reduction in Douglas Shire ...... 151 Project 2: Determination and Demonstration of Agricultural BMP in the Saltwater Creek Catchment of Douglas Shire ...... 154 Project 3: Control of Point Source Discharges of Sediment & Nutrient in Douglas Shire ...... 157 Project 4: Protection and Restoration of Riparian and Wetland Areas in Douglas Shire ...... 159 Project 5: Monitoring & Modelling of Sediment & Nutrient Flow Within & From Waters of Douglas Shire ...... 162 Appendix D. Relationship of WQIP Management Actions to FNQ NRM Ltd Management Actions and expanded table of actions relating to Table 4.6 ...... 165

Table A: Priority management actions determined that will reduce nutrient and sediment loads entering the GBR lagoon for Douglas Shire...... 5 Table B: Commitments to WQIP implementation...... 17 Table C: Implementation Schedule for WQIP...... 19 Table 1.1: Principal land uses in Douglas Shire...... 35 Source: Table from Report 5 P1A2 ID of BMPs...... 35 Table 1.2: Demographic data for the Douglas Shire...... 44 Table 2.1: Reaches in the catchments and Coastal Waters sections of Douglas Shire.... 46 Table 2.2: Potential Environmental Values ...... 47 Table 2.3: Median concentrations and WQOs for a range of water quality parameters for the identified reaches of Daintree and Mossman Rivers (Median values in red if they exceed the WQO)...... 53 Table 2.4: Discharge and pollutant loads of TN, TP and TSS at Upper Mossman and Upper Daintree from monitoring and modelling studies...... 60

22 Table 2.5: The loads of pollutants of concern in the four catchments in Douglas Shire. Diffuse loads were obtained from CSIRO modelling studies and are subject to large errors. Point source loads were taken from Appendix G of Final CSIRO Modelling report 2004 - 2005. The negative value for sediment loads in the Mossman estuarine region denotes there is more sediment deposited than eroded in this region...... 61 Table 2.6: Percentage contributions to the cleared land diffuse source loads from the three principal land uses...... 63 Table 2.7: Contributions of each catchment to pollutant loads in pre-European conditions and current day...... 64 Table 3.1: Water withdrawal rates from the three points of urban supply in Douglas Shire...... 70 Table 4.1: Industry Codes of Practice in Queensland...... 76 Table 4.2: Producer surplus* (million A$ per annum) to both terrestrial and marine industries from selected management actions, based on sediment management...... 82 Table 4.3: Summary of relative social and economic acceptability in Douglas Shire of actions for managing improvements in water quality, where high indicates a positive effect and low a negative effect; neutral indicates effects are mixed and small...... 84 Table 4.4(a): Pollutant load and management action targets for the Daintree River catchment...... 90 Table 4.4(b): Pollutant load and management action targets for the Mossman River catchment...... 90 Table 4.4(c): Pollutant load and management action targets for the Mowbray River catchment ...... 91 Table 4.4(d): Pollutant load and management action targets for the Saltwater Creek catchment ...... 91 Table 4.4(e): Pollutant load and management action targets for the Coastal Strip1 ...... 92 Table 4.5: Summary of acceptability, and relative effectiveness of management actions for reducing pollutant loads...... 92 Table 4.6: Management actions, timelines, approximate costs and proposed accountabilities...... 95 Table 6.1: Commitments to WQIP implementation...... 120 Table A.1. Water quality guidelines/objectives for each environmental value (based on local reference data and NWQMS)...... 129 Table A.2: Summary of EVs and draft WQOs for each segment of Douglas Shire waterways ...... 131 Table B.1 Rainfall scaling factors applied to calibrate SIMHYD rainfall run off model for the ‘forest’ land use group, within Region 1 (see Figure A.6) ...... 137 Table B.2 Sub catchments within the two hydrologic regions within the Douglas Shire, relating to the rainfall scaling (Table A.1) calibration and the SIMHYD parameters for ‘forest’ and ‘non forest land use groups (Table A.3)...... 141 Table B.3 The SIMHYD parameters applied within the 2 hydrologic regions used within the EMSS model...... 142 Table B.4 Event mean concentrations (EMC) and dry weather concentrations (DWC), for each land use category used in the model EMSS, expressed in mgl-1...... 142 Table B.5: Estimated average concentrations of dissolved inorganic nitrogen DIN, dissolved organic nitrogen DON, filtered reactive phosphorus FRP and dissolved

23 organic phosphorus DOP in runoff from land uses Wet Tropics Regions (after Brodie et al., 2003)...... 143 Table B.6. C factor and average slope values used in the RUSLE calculations for the Douglas Shire Project. Average slope values for each land use were obtained from the DEM. N/A means ‘not applicable’...... 145 Table B-7. Percentage reduction in total Shire pollutant loads as a result of applying management actions or simulating possible land use changes. The figures in brackets show the percentage change in load within that subcatchment...... 146 Table AD- 1: Linkage of management actions to FNQ NRM Ltd management action targets...... 165 Table AD-2. Range of tasks defining management actions. Refer to section 4.8 for explanation of category...... 167

24

Acknowledgements

The Douglas Shire WQIP was managed by Peter Bradley of Douglas Shire Council. The WQIP and associated projects were funded by the Australian Government’s Coastal Catchments Initiative, a programme of the Natural Heritage Trust.

The plan was drafted by Richard Davis. Comments and assistance were received from Neal Hardy, Department of Environment and Heritage and John Bennett and Lindsay Delzoppo of the Queensland Environmental Protection Agency, Dr Tony Webster and Dr Frederieke Kroon of CSIRO Sustainable Ecosystems, Dr Tim Ellis and Dr Rebecca Bartley of CSIRO Land and Water, Darryl Parker of Mossman Agricultural Services, Greg Keith of Douglas Shire Council and Professor Brian Roberts of CSIRO Sustainable Ecosystems and the Douglas Shire Joint Venture Partners. Terry Melchert, CEO of Douglas Shire Council. Ian Barton of Douglas Shire Council is thanked for Financial Administration support. Allan Dale, FNQNRM Ltd for identifying linkages between WQIP and NRM Plan. Community water monitoring volunteers who collected 18 months of ambient water samples.

Individuals and organisations that contributed to the various workshops, meeting and provision of comments on the draft Water Quality Improvement Plan are also gratefully acknowledged.

25

Chapter 1. Introduction

Summary o The Queensland and Australian Governments reached agreement in late 2003 on the Reef Water Quality Protection Plan (RWQPP), to protect the waters of the Great Barrier Reef (GBR). Water Quality Improvement Plans (WQIPs) are being developed to help reduce pollutant loads to these coastal waters. The RWQPP identifies Douglas Shire as an area where a WQIP will be developed. o The Wet Tropics NRM Board has developed a natural resource management plan for the region under the NHT arrangements. The Plan will be the primary vehicle for delivering Australian and Queensland Government investments for implementing the Douglas Shire WQIP. o Douglas Shire contains parts of two World Heritage Areas (WHAs) – the Wet Tropics and the GBR WHAs. The western part of the Shire consists of steep, largely vegetated mountains and hills, giving way to alluvial plains in the east. The Shire has four major rivers– the Daintree, Mossman and Mowbray rivers and Saltwater Creek. There are areas of Mangroves around some of these river estuaries and along the coast. o Sugar cane is the principal crop grown in the Shire. There is some beef grazing in the mid- Daintree catchment. Tourism, based on the two WHAs, is a major activity in the Shire with Port Douglas the centre of this activity.

1.1 Background to the WQIP

1.1.1 Great Barrier Reef Water Quality Action Plan Since European settlement in the 19th Century, use of the north Queensland coast has grown and intensified to include commercial fishing, tourism, shipping, scientific research and recreational pursuits such as boating, fishing and diving. During this period there has also been significant urban and rural development of the mainland adjacent to what is now the GBR Marine Park. These activities threaten the considerable environmental values of the reef region unless managed carefully.

Since c1850, pollutant loads are estimated to have increased to the Reef lagoon many- fold5: • Sediment loads between 300-900% • Phosphorus loads between 300-1,500% • Nitrogen loads between 200-400%

5 GBR Water Quality Action Plan Exec Summary, November 2001.

26 The increases in nutrient loads (nitrogen and phosphorus) are of concern due to their potential to cause eutrophication and disrupt the Reef’s ecosystems. As well as transporting nutrients, sediment loads can smother seagrass beds and inshore coral reefs.

In 2001, in response to these concerns, the GBR Ministerial Council authorised development of a Water Quality Action Plan to reduce these pollutant loads over a 10 year period. The Plan identifies the pollutant load reductions to be achieved for each of the 26 catchments contributing to the Great Barrier Reef lagoon. Two of these catchments – Daintree and Mossman – fall within Douglas Shire6.

1.1.2 The Great Barrier Reef Water Quality Protection Plan The Queensland and Australian governments reached agreement in late 2003 on a plan to protect the GBR and lagoon from declining water quality – the RWQPP. The Plan is based on previous reviews that identified the extent of water quality deterioration since European settlement7. The causes were identified as being land degradation within the catchments, urban development, vegetation clearing, water use practices, wetland drainage leading to reduced trapping of sediments and nutrients, and coastal developments on acid sulphate soils.

While there was little evidence of these developments causing degradation of the outer Reef, there was clear evidence that they were affecting the inshore reefs, estuaries, and important near-shore areas. At the same time, the Plan was sensitive to the economic importance of industries within the coastal catchments including beef, sugar, horticulture, tourism, mining, and fishing industries8.

The RWQPP has the twin objectives of: 1. reducing the pollution load from diffuse sources into the water entering the Reef; and 2. rehabilitating and conserving areas of the Reef catchments that play a role in reducing pollutant loads.

Pollutant loads have been selected as the targets for the plan because they provide a measure of the total quantity of pollutant able to be mobilised in receiving waters such as the Barrier Reef lagoon over an extended period. Pollutant concentrations are used for river health targets because they provide a measure of the pollutant available to aquatic organisms in the water column.

In determining catchments/basins of high priority for the RWQPP a risk assessment process that utilised the criteria of Bio-physical risk, Social risk, Development risk, and Risk to marine industries. The RWQPP recognises that the risk assessment process requires further work to be undertaken to clarify and improve the risk assessment process.

6 Note that the catchments defined in the Great Barrier Reef Water Quality Action Plan are larger than the catchment definitions employed in the current study. 7 Great Barrier Reef Catchment Water Quality Action Plan: A Report to Ministerial Council on targets for pollutant loads, Great Barrier Reef Marine Park Authority, November 2001. 8 “Industries, Land Use and Water Quality in the Great Barrier Reef Catchment”. Productivity Commission, Canberra, February 2003.

27 Arguments could be given to maintaining the integrity of relatively healthy catchments from the pressures of population growth and industry diversification, as well as proving- up management strategies in small catchments with shorter response time before addressing larger catchments subject to greater seasonal and inter-annual variations.

A significant component of the CCI is focused on protecting the GBR. The Douglas WQIP and its Interim Projects (Appendix C) have trialled approaches and methodologies that will be rolled out as appropriate, in other GBR catchments.

A recent initiative by Australian and Queensland Government is the formation of the Reef Water Quality Partnership (Reef Partnership), which formalises ongoing collaboration between Australian and Queensland Government agencies and five of the regional NRM bodies of the GBR catchments. The role of this body is to facilitate RWQPP actions H1, H2, I4, I5 and I6, which addresses coordinated water quality target- setting, monitoring and reporting to support the implementation of the Reef Plan.

1.1.3 The Coastal Catchments Initiative The Australian Government, through the Coastal Catchments Initiative (CCI), is committed to improving the condition of Australia’s coastal waters through joint action with State and local governments. As a first step this will be achieved through the development of Water Quality Improvement Plans (WQIPs) for those coastal waters.

WQIPs – prepared in accordance with the Australian Government’s Framework for Marine and Estuarine Water Quality Protection - are consistent with existing government strategies such as the National Water Quality Management Strategy and (where relevant) the National Principles for the Provision of Water for Ecosystems. The Plans will incorporate the environmental values of coastal waters, the water quality issues that threaten these values, the sources (diffuse and point, including atmospheric and internal sources) of pollutants that are contributing to these issues, the pollutant load reductions to be sought from these sources, the river flow objectives for maintaining ecosystem health, the management interventions needed to achieve pollutant load reductions, and the “reasonable assurance” that the WQIP, if implemented, will achieve its targets. Monitoring systems will be established in the targeted catchments to allow the cost- effectiveness of management interventions to be assessed.

The sediment and nutrient reduction targets and the likely effectiveness of management actions have been set using water quality models because of the limited amount of water quality monitoring data available. Because of the paucity of good data in this part of Australia, these model predictions are subject to considerable error and so this plan takes an adaptive implementation approach, drawing on the monitoring data, whereby the WQIPs are regularly reviewed and modified. The key inputs to this adaptive management framework are discussed further in Section 4.9.1. Consequently, the reasonable assurance that the management actions in this plan will achieve the targets has to be qualified by the need to modify the targets and the management actions during the life of the plan as better information becomes available from the monitoring program.

28 The Douglas Shire Council and any other bodies providing this reasonable assurance will be involved in these revisions.

Some of the parameters governing the development of WQIPs include: • meeting Australia’s international environmental obligations; • implementing nationally agreed resource protection strategies, eg NWQMS; • local, state and Australian Government cooperation and leadership; • use of best available scientific knowledge, within an adaptive implementation framework; and • community and industry involvement.

Under the RWQPP WQIPs will be developed by local governments or regional NRM bodies, consistent with the Framework for Marine and Estuarine Water Quality Protection. There are many catchments contributing pollutants to the Barrier Reef system, ranging from the large – e.g. Burdekin and Fitzroy - to the small catchments – e.g. Plane and Murray catchments. The Plan will be progressively implemented in these catchments, drawing on the readiness of communities and local authorities to participate, the seriousness of the issues and the extent of knowledge.

The Douglas Shire WQIP has been prepared with assistance from the Australian Government’s Natural Heritage Trust and the Queensland government. Six projects have been undertaken to help prepare the Plan. Projects 1-5 (see Appendix C) provided information on sources of point and diffuse source sediments and nutrients and their management through source reduction and interception during transport. The sixth project assisted preparation of Environmental Values and Water Quality Objectives for Douglas Shire waters.

The Queensland Environmental Protection Agency (QEPA) was contracted by DEH to assist DSC with the establishment of EVs and WQOs. The framework for setting EVs and WQOs is well established through the NWQMS and is embedded in the Queensland Environmental Protection (Water) Policy 1997 [EPP (Water)]. The framework is shown in Figure 1.2.

29 Community wants Environmental and needs values Feedback loop

Management goals

Impacts not acceptable Water quality Water quality guidelines objectives

Alternative Consider social, management economic & strategies environmental values

Agreed water quality Impacts acceptable objectives

Management Monitor and actions review

Figure 1.2 Process for establishing Environmental Values and Water Quality Objectives, adapted by the Queensland Environmental Protection Agency from the ANZECC Water Quality Guidelines (2000).

1.1.4 Wet Tropics Natural Resource Management Plan The Wet Tropics NRM Board was established as the Regional Body to oversee natural resource management (NRM) in the Wet Tropics, covering the local governments from Douglas Shire in the north to Hinchinbrook in the south, and as far west as Atherton Tablelands. It has now been succeeded by the Far North Queensland NRM Ltd.

The North Queensland Afforestation Association (NQAA) is an incorporated association of local government in the region which supports and administers various NRM activities including the Wet Tropics Vegetation Management Program, Land for Wildlife and the North Queensland Farm Forestry Extension Program.

The NRM Board and the NQAA have jointly developed an accredited NRM plan9 under the NHT arrangements. The plan identifies a range of NRM issues, including some of relevance to this WQIP: • riparian and in-stream degradation through encroaching adjacent land uses and catchment clearing and development; • inadequate management and allocation of surface and ground waters;

9 FNQ NRM Ltd & Rainforest CRC (2004) Sustaining the Wet Tropics: A Regional Plan for Natural Resource Management 2004-2008. FNQ NRM Ltd, Innisfail (240pp).

30 • land management practices at the individual property level that degrade natural values; • failure to implement best practices in primary industry; and • declining water quality due to sedimentation and other forms of diffuse pollution, in addition to disturbance of acid sulphate soils, point source pollution and salt water intrusion.

A Memorandum of Understanding has been signed between the NRM Board and Douglas Shire Council to work together to protect the GBR from land based pollution. This allows for Douglas Shire Council and other parties to draw on regional funding, where appropriate, to help implement the WQIP and for the NRM Board to incorporate findings and final WQIP into the NRM Plan.

1.2 Douglas Shire

1.2.1 Physical characteristics There are four catchments within the Douglas Shire Council’s jurisdiction – Daintree, Mossman, Saltwater, Mowbray (Figure 1.2) that have been described in this Plan. The four catchments cover an area of 186,000 ha.

Mangrove wetlands, sandy beaches and inshore fringing reefs characterise the coast. There are small islands, notably Snapper Island at the mouth of Daintree River and Low and Woody islands off Newell. The numerous coastal reefs include the reefs around Snapper and the Low Islands, Morey Reef off Pt Douglas, Wentworth Reef south off Pt Douglas, Alexandra Reefs, Yule Reef and Garioch Reef in the southern section of the Shire. The seagrass beds that occur off Port Douglas, Newell Beach and Yule Point provide habitat for dugong. There are extensive areas of mangroves at the mouth of the Daintree River extending upstream to above the ferry crossing. Smaller areas of mangroves occur at the mouths of the other rivers in the Shire.

The GBR, comprising the world’s largest system of coral reefs, together with inter-reef lagoons, seagrasses and mangroves, occupies a swathe between 25 and 45 kms offshore along the length of Douglas Shire. The Great Barrier Reef was declared as a Marine Park in 1975 and, due to its international importance, was inscribed on the World Heritage List in October 1981. About 98 per cent of the WHA is within the GBR Marine Park, the remainder being Queensland waters and islands.

31

Figure 1.2. Catchments addressed in this WQIP.

The Marine Park supports a high degree of biological diversity due to the variety of ecosystems present and the immense scale of the area. It provides habitat for approximately 1500 species of fish, 350 species of hard corals, over one-third of the world’s soft coral and seafen species, 5000 mollusc species, six of the world’s seven species of marine turtles and more than 30 species of marine mammals. The Marine Park represents an important area for the conservation of many rare or threatened species such as marine turtles, dugong, seabirds, humpbacks and other whales. This extraordinary biodiversity and the interconnectedness of species and habitats make the GBR and the surrounding areas one of the richest and most complex natural systems on earth.

In additional to its environmental values, the GBR provides economic activity worth more than A$1 billion per annum. Tourism provides about A$650 million per annum; commercial fishing around A$150 million per annum and the large recreational fishing and recreational boating sector is worth about A$120 million per annum.

32 Major reefs off-shore from Douglas Shire includes (from north to south) Rudder Reef, Chinaman Reef, Opal Reef, Tongue Reef and Batt Reef. Trinity Passage to the Coral Sea bounds these reefs in the south.

1.2.2 Activities These coastal waters are used for a wide variety of commercial and non-commercial uses. Commercial fishing includes netting, trawling and line fishing. No figures are available for the commercial fish catch within the region of Douglas Shire – however, commercial fishing accounts for $119m in 1999-2000 for the Reef as a whole10. Tourism is a particularly important commercial activity in the Port Douglas region accounting for $64.5 million p.a. Tourist activities - wildlife viewing (dugongs, turtles), snorkelling, scuba diving and fishing - are concentrated in the Double Island North to Port Douglas region.

Recreational activities in waters adjacent to Douglas Shire include fishing, spear-fishing, snorkelling and boating. These activities are particularly concentrated on East and West Hope Island Reef, Pickersgill Reef, Evening Reef, Rudder Reef, Tongue Reef, Snapper Island Reef, and Batt Reef.

In addition, these coastal waters retain considerable environmental values consistent with the general environmental values of the GBR Marine National Park. All waters beyond the low tide limit form part of the GBR Marine National Park and the GBR WHA. For example, although the GBR Dugong Protection Areas are further south, dugongs are frequently sighted in the inshore waters from Port Douglas north to Cape Kimberley11. These threatened mammals feed primarily on sea-grasses in this region and, amongst other threats, are vulnerable to anthropogenic activities that threaten these food sources.

The region of the Reef waters between 5km offshore and the outer reef is included in the Cairns Area Plan of Management (2002). Originally, the waters between the coastline and 5km offshore were excluded from this plan but have recently been incorporated into the Reef Zoning Plan (2004). The Cairns Area Plan of Management provides detail on the activities that are permitted in the region offshore to Douglas Shire with the aim of “protecting and conserving identified values of the Cairns Area, while allowing for reasonable opportunities to access and use the Planning Area”.

The Reef Zoning Plan incorporates the previously excluded near-shore areas off Douglas Shire and identifies the activities that are permitted in considerable detail in this region. For example the Marine National Park Zone along the coast south of Alexandra Shoals will provide protection to Garioch Reef and Unity Reef and restrict fishing usage in a less accessible area of the coastline.

While these zoning schemes can prevent some of the damage from activities that are carried out within the National Park itself, they do not address the problem of damage caused by activities exogenous to the Park. The RWQPP and supporting catchment

10 Productivity Commission report Ch 4. 11 GBR Zoning Plan – Basis for Decision, June 2003.

33 WQIPs facilitate planning and management to reduce the threat from the transport of contaminants from catchments adjacent to the Reef.

1.2.3 Geography of Douglas Shire Landforms12 Steep to precipitous mountains and hills dominate the Shire. They form rugged highlands that surround a narrow coastal plain to the north, south and west. The maximum distance between the Coral Sea and the highlands is approximately 12 kilometres.

The highlands reach their highest elevation in mountain ranges along the western margins, south of the Daintree River. Slopes commonly exceed 30% and are often close to 100%. The highlands to the east and north of these ranges contain lower mountains and hills formed on low grade metamorphic rocks. Basic volcanics similar to basalt are inter-bedded with these rocks and outcrop in the north-east between Cape Kimberley and Daintree. Although the highlands of metamorphic origin are not as high as the ranges they are very rugged with slopes commonly exceeding 30%.

Extensive alluvial fans have developed along the edge of the highlands. The fan material is predominantly of metamorphic origin but has a basaltic influence in the north-east. One very small granitic alluvial fan occurs in the upper reaches of Whyanbeel Creek. Slopes vary from less than 1% on the lower ends of the fans to as high as 10% on the upper slopes.

The rugged highlands are drained by numerous streams that have incised into the hard rock. These streams carry material eroded from the highlands to the Coral Sea. The eroded material has been deposited enroute to form alluvial plains, alluvial terraces and flood plains. Many of the alluvial plains and terraces represent older deposition. However, flooding is still active on the lower flood plains which continue to form by deposition. Swamps are common in low lying areas.

The alluvial plains, terraces and flood plains merge into beach ridges and tidal flats of marine origin towards the coast. The beach ridges have formed by the deposition of sandy material in a series of ridges and swales by wave action with subsequent reworking by wind to form sand dunes in a few locations. The beach ridges are very gently undulating with slopes mainly between 1% and 3%. The tidal flats are low-lying areas inundated by sea water during high tide and are mainly covered with mangroves.

12 Taken from GHD draft report “Strategic Management Plan for the Major Rivers and Streams of the Douglas Shire” for the Douglas Shire River Improvement Trust.

34 Land use and vegetation Sugar cane production is the largest agricultural activity in the Shire occupying 8000 ha. It dominates the cleared lowlands consisting of alluvial fans, alluvial plains, terraces and flood plains, except in the upper valley of the Daintree River where grazing is the predominant land use. The natural vegetation has been completely removed in these areas except where the freshwater and brackish swamps have not been drained for use. Sugar is also grown on parts of the beach ridges. Grazing of beef cattle is the next largest agricultural activity accounting for approximately 5,700 ha. Grazing occurs primarily in the mid-Daintree catchment with small pockets in the other catchments of the shire.

Most of the mountains and hills in the highlands (89,900 ha) are designated either National Park or State Forest. The vegetation in these areas remains relatively undisturbed rainforest and eucalypt open forest. However, feral pigs are present in these areas and are believed to cause significant disturbance to the soils of the region. However, 12,100 ha of rainforest and eucalypt open forest are in private tenure, the bulk of which appears to be undisturbed. On the hillslopes fringing the coastal plain much of the original vegetation has been removed, by clearing and fires which have spread from adjacent sugar cane farms. There are small amounts of logging on private land in the upper Daintree Valley.

Table 1.1: Principal land uses in Douglas Shire. Source: Table from Report 5 P1A2 ID of BMPs Sugar Cane • Daintree 1,169 ha • Saltwater 2,547 ha • Mossman 2,795 ha • Mowbray 1,486 ha • Total 7997 Grazing Approximately 5,700 ha Horticulture • Papaws 15 ha • Bananas 38 ha • Lychee 20 ha Aquaculture 1 QEPA licenses issued 5 DSC permits issued Protected areas • Daintree 134,200 ha • Saltwater 7,500 ha • Mossman 4,700 ha • Mowbray 6,900 ha • Total 153,300 Urban1 • Daintree 18 ha • Mossman 184 ha • Creeks (Port Douglas) 310 ha • Total 512

35

The majority of the public and private land in the highlands of the Shire is included in the Wet Tropics WHA. This Area of 890,000 ha stretches as a broad belt of land from Cooktown in the north for 500 kms almost to Townsville in the south. The area represents the largest remaining fragments of tropical rainforest in Australia and contains a remarkable diversity of mammals, frogs, birds and invertebrates, many of which are endemic to the region.

About 75 ha of land is used to grow tree crops, mostly in the upper Daintree valley but also in the upper reaches of Whyanbeel Creek.

About 500 ha of residential, rural residential and recreational areas are scattered throughout the coastal plain on beach ridges, alluvial plains, terraces and alluvial fans.

Climate13 The Shire is part of the Wet Tropical Coast and is characterised by very high rainfall. There is a rainfall gradient on the coastal plain from over 3000 mm in the Daintree area to 2000 mm south of Port Douglas. A sharp gradient also exists in the highlands with very high falls occurring on the eastern part and much lower falls on the western edge.

The rainfall is uneven over time as well with more than 80% of the annual total falling in the four summer months from December to April. Although the rainfall has a strong summer dominance, significant falls can occur during the winter period. A feature of the rainfall is the very high intensities that can be experienced especially when associated with tropical low pressure systems. This gives rise to high intensity flow events in the rivers of the Shire with associated heavy erosion.

Despite the high rainfall totals the strong seasonal distribution results in evaporation exceeding rainfall on average from May to December throughout the Shire.

Soils The steep to precipitous mountains and hills of the highlands have permeable, red and yellow gradational soils in which surface texture gradually increases with depth. The surface of the soils on metamorphic rocks varies from sandy clay loam to light clay and grades into finely structured red or yellow clay. Weathered rock occurs between 60 cm and 2 m depth.

A range of soils occur on the alluvial fans below the highlands. On fans of metamorphic origin the soils range from red gradational soils, through yellow gradational and duplex soils to bleached, mottled grey gradational soils. Weathered parent material usually occurs between 60 and 120 cm depth. Friable red and yellow gradational soils with a sandy loam to clay loam surface that grades into clay loam to clay subsoil dominate in the better drained areas. Yellow gradational soils and yellow and grey duplex soils with a

13 Taken from GHD draft report “Strategic Management Plan for the Major Rivers and Streams of the Douglas Shire” for the Douglas Shire River Improvement Trust.

36 fine sandy loam to silty clay loam surface that abruptly overlies mottled clay subsoil predominate in the lower slopes and seepage areas.

The soils on the alluvial plains, terraces and flood plains are best subdivided into three groups based on drainage. The well drained soils vary from red, yellow and brown silty clay loams to silty clays and heavier clays. The well drained soils merge into a range of poorly drained soils with mottled yellow and grey clay subsoils. The soils have a clay loam to clay surface that either gradually changes into, or abruptly overlies, a clay subsoil of low permeability. The subsurface is usually bleached and the surface may be highly organic around the margins of swamps. There are numerous freshwater and brackish- water swamps on the coastal plain containing gleyed soils with a highly organic loam surface grading to bleached silty clay loam subsurface that abruptly overlies waterlogged and mottled grey, yellow and brown subsoil.

The beach ridges contain a range of sands with a dark surface that becomes paler with depth. Further inland the pale subsurface overlies brown and yellow sand which often has high organic matter content. Smaller areas of red sandy loams and gradational soils and yellow sands are also included. The soils of the tidal flats are mainly reworked beach ridge sands although there has been some addition of finer textured deposits in most areas. The dominant textures range from clayey sand to sandy clay with clays and muds predominating in only a few minor areas.

1.2.4 Study Catchments of Douglas Shire Daintree River The Daintree River has the largest catchment in the Shire with an area of ~1332 km2. The mean annual discharge of the Daintree River is 907 000 ML14 although this varies considerably seasonally and inter-annually. The river rises on the Great Dividing Range but by comparison with the other streams of Douglas Shire, it descends relatively gradually to the coastal plain. The river enters a broader estuarine section about 5km above the Ferry crossing. Below the ferry, the river broadens further into a wide estuarine channel with an extensive system of minor tidal estuarine channels leading to the ocean.

Stewart Creek is the major tributary of the Daintree in its alluvial tract. Stewart Creek and its tributary Douglas Creek have steeper alluvial tracts than the Daintree and these include significant lengths of non-tidal alluvial channel.

Streamflow is perennial but strongly seasonal in the Daintree River and these two tributaries (Figure 1.3). The latter may cease to flow in some dry seasons. All other tributaries are ephemeral.

Bed material is predominantly sand and gravel from where the Daintree River emerges from the rainforest. There are extensive sand bars once the river enters the tidal section above the Ferry. The river is subject to tidal influence for the entire alluvial tract.

14 This data and other information in this section comes from Russell, McDougall and Kistle 1998. “Fish Resources and Stream Habitat of the Daintree, Saltwater, Mossman and Mowbray Catchments.” DPI, Queensland.

37

The banks of the Daintree River are cleared and grassed from the river’s emergence from forest, apart from less accessible areas where riparian rainforest remains. Grazing is the predominant land use in upper section of the river floodplain, interspersed with sugarcane in the lower sections down to the Ferry crossing. There is also some tourism boating on the river around and below Daintree township. Once the river enters its estuarine section above the Ferry, the vegetation changes to mangroves and associated vegetation. There is a mixture of grazing and sugar cane in this section. The mangrove swamps increase in extent below the ferry and there are no further commercial land use activities from here to the river mouth. There are over 2100 ha of mangroves in the lower reaches of this river.

Monthly Mean flows - Daintree River at Bairds

300000

250000

200000

150000

Megalitres 100000

50000

0 Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep

Figure 1.3. Monthly mean flow (1968/89-2002/03) in the Daintree River at Bairds station (from QDNRMW)

Localised bank erosion is apparent along the Daintree River, especially at the downstream end where the channel is wide and wind fetch is large. The principal mechanism for this erosion appears to be wave action, as the sediment eroded from the banks accumulates in beaches at the foot of the bank rather than being removed by the river. Bank damage from the wash of tourist boats also occurs mostly downstream of Daintree village. Bank erosion is also apparent at several sites along both Stewart and Douglas Creeks. This may have been exacerbated by the removal of riparian vegetation. A number of major cutoffs have occurred on Douglas Creek since 1957. It is not clear if these cutoffs are the result of natural dynamics or a response to land use change.

Much unvegetated sand is visible in the channel of the Daintree River, largely occurring as point bar deposits on the insides of meander bends. At some locations there has also been extensive overbank sand deposition. Sandy deposits are visible in the channel as far upstream as the mouth of the gorge, suggesting that some of the sand is derived from the largely forested Daintree catchment where it is generated mainly through natural processes. Sand is also being delivered to the Daintree estuary by Stewart Creek. At least some of this

38 sand is likely to have been liberated by the recent channel changes along Douglas and Stewart Creeks.

Flood flows in the Daintree estuary are reported to be highly turbid. Waters flowing from the gorge are believed to be relatively clear and so the channel changes on Douglas and Stewart Creeks are a possible contributing factor along with continuing erosion in the other small tributaries which feature sandy clay banks (eg. Martins Creek). Agricultural development on sloping lands is also likely to play a role, as land use practice has been found to exert a major influence on suspended sediment load in Queensland's humid tropics.

Population density is extremely low with only 738 people resident within the Daintree and Saltwater catchments combined15. Ninety-five percent of the catchment is undeveloped forest or wetland, 87% of which is within the Wet Tropics WHA. The remaining area is almost equally divided between sugar cane (48 km2) and grazing (45 km2). There is a small amount of horticulture in the catchment. The village of Daintree lies at the junction of the Daintree River and Stewart Creek, and the coastal village of Wonga to the south of this catchment.

Saltwater Creek Saltwater Creek has a catchment area of ~136km2. This catchment is characterised by some of the largest rainfall quantities and intensities in the Shire, with an average annual rainfall of 2,591mm. The Creek has an annual average discharge of 46,000 ML.

Bed sediment size decreases quite rapidly from boulders and cobbles at the upstream end, to gravels and then to sand for considerable distances. However, the downstream fining of sediments is interrupted by inputs of coarse sediments from tributaries. For example, the bed of Whyanbeel Creek is sandy upstream of its confluence with Little Falls Creek, but becomes gravelly further downstream because of inputs of coarse bed material from Little Falls Creek and High Falls Creek.

The riparian areas are covered in rainforest vegetation to just above the Miallo Road bridge, with this vegetation narrowing downstream of the White Road ford. Below this point, there is a mixture of rainforest and grass on the streambanks as far as the estuarine area. Mangroves are the predominant vegetation in the estuarine area. Sugar cane fields abut the riparian vegetation down to the estuary.

The Creek and its major tributaries flow parallel to each other for considerable distances on the coastal plain. Creek flow is perennial but markedly seasonal (Figure 1.4). Flow may cease in the smaller tributaries in some dry seasons.

15 GBRMPA Fact Sheet.

39 Mean Monthly Flow - Saltwater Ck at O'Donohues Road

16000 14000 12000 10000 8000 6000 Megalitres 4000 2000 0 Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep

Figure 1.4. Mean monthly flows (1990/91-1995/6; 1998/9) in Saltwater Creek at O’Donoghues road (QDNRMW)

The headwaters are forested (70% of the area) while the coastal plain portion of the catchment is under intensive farming, predominantly sugar cane (25% of the catchment). There are only small areas of mangroves (<200 ha) at the mouth of this river. The beach village of Newell Beach lies on the border of this catchment and the Mossman catchment.

Mossman River The Mossman River, South Mossman River and Cassowary Creek, with a combined catchment area of ~208km, rise on mountainous terrain of the Great Dividing Range before falling to the coastal plain. River flow is perennial but markedly seasonal (Figure 1.5). Rainfall at Mossman town is 2208 mm and the annual average river discharge is 224,000 ML.

40 Mean monthly flows - Mossman River at Mossman town

70000 60000 50000 40000 30000

Megalitre 20000 10000 0 Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep

Figure 1.5. Mean monthly flows (1948/49-1960/61; 1988/89-2001/02) in the Mossman River at Mossman town (QDNRMW)

The Mossman River emerges from the Mossman Gorge about 10 km from the coast as a system of anabranching channels at the upstream end of its alluvial tract. The reduction in energy as it enters these anabranches results in a reduction of sediment transport capacity with consequent deposition of sediment loads. Where the river emerges from the Gorge, its bedload includes boulders and cobbles while further downstream near Mossman, the sediments become finer and the river contracts to a single sinuous channel. Through this section the outer banks are covered in rainforest vegetation although the central islands are either cleared for cultivation or covered in low scrub and subject to occasional high-energy floods. This section of the river is in excellent condition with good water quality and a high abundance of fish.

Further downstream to the tidal limit the river coalesces into a single channel with a sandy bed. The banks are covered in rainforest vegetation with sugar cane fields behind. The river bed continues as sandy to the river mouth, approximately 2km below the junction with the South Mossman River. The river banks in the estuarine section are covered with mangrove vegetation with sugar cane fields behind the higher verges.

Less sand is visible in the river bed and at some tributary sites today than in the mid 1950's (GHD, p106). The presence of sand deposits in pools within the Gorge demonstrates that sand is being delivered to the river from the forested catchment upstream. Bank erosion is apparent at many sites in the Mossman estuary. Some fairly major changes in channel position of the Mossman River and its distributaries, as the result of natural processes, have occurred in the anabranching system of channels near the river mouth since the 1950's.

Most of this catchment is undeveloped with forests and wetlands accounting for 78% of the total catchment area. This catchment contains the largest area of sugar cane in the Shire (4000 hectares). Almost all this activity occurs on the floodplain of the Mossman River and

41 its tributaries and encompassing 20% of the catchment. There are only small areas of mangroves (<150 ha) at the mouth of the river16.

The seat of local government, Mossman township (population 1800), lies at the junction of the Mossman and South Mossman Rivers. Apart from being the administrative centre for the region, the town also supports the Mossman sugar mill and provides services for tourists heading north to the rainforest areas and for visitors to Mossman Gorge. The town’s sewage treatment plant and the Mossman sugar mill discharge waste products into the South Mossman River. The coastal village of Cooya also lies in this catchment.

Mowbray River The Mowbray catchment as used in this report includes the short coastal creeks that enter the sea between the Mowbray and Mossman Rivers. The Mowbray River and its tributaries Collards Creek, Spring Creek and Rocky Creek, rise on elevated terrain in the Great Dividing Range and plunge steeply to a short alluvial reach on the coastal plain. Annual average rainfall is only 1960 mm and annual average discharge is 14,000 ML.

The stream beds are bouldery at the upstream end of the alluvial section and gravelly deposits are apparent on the river bed even as far downstream as the river mouth. The flow regime is seasonally intermittent: towards the end of the winter months (dry season) water seeps through the gravels of the riffles in many places, and pools of water are the only permanent water bodies. However, in the summer (wet season) the river carries a considerable discharge.

Unlike the other catchments in the Shire, the Mowbray River does not rise in National Park or forested land. Its upstream catchment contains some grazing and rural residential land uses before it enters the WHA. Once it emerges from the WHA the river is in good condition with rainforest to the riverbanks with little introduced weeds. Water quality is excellent and there are numerous fish in this mid-section. Further downstream below the confluence with Collard Creek, there is an active floodplain with rainforest riparian vegetation backed by sugar cane fields. The river reverts to a single channel leading towards the estuary. Downstream of its confluence with Spring Ck the Mowbray River straightens with thin vegetated riparian strip predominantly mangroves. There are further sugar cane fields behind this riparian strip. The river broadens and meanders in the estuarine section with numerous mudbanks. There are fringing mangroves in this section, backed by further sugar cane fields. The river mouth is split in two with primary flows through the south exit.

Mowbray River catchment in the south has an area of 174km2. Most of the Mowbray catchment is forested (72%) with only small areas allocated for sugar cane (11%) and grazing (9%). It is the driest catchment in the Shire, and much of the water flowing in this catchment moves within small coastal streams rather than in the Mowbray River itself.

The largest town in the Shire, Port Douglas, is located within the Mowbray Catchment. Port Douglas has grown rapidly over the last three decades from a small fishing village of 200

16 Russell, McDougall and Kistle Table 4.

42 people to a major tourist destination17. The town now has a population of 4000 and depends almost entirely on tourist activities within the Great Barrier Reef Marine National Park and the Wet Tropics World Heritage Area.

1.2.5 The Economy The Douglas Shire was the fastest growing Shire in the Far North Region 1991 – 1998. With two internationally-renowned tourism destinations in the Shire (Port Douglas and the Daintree National Park), and positioned between the Wet Tropics and GBR WHAs, tourism is the largest sector of the local economy. Total expenditure on tourist accommodation in the Shire in the year ending September 2003 was $81 million (OESR, 2003) – a 33% increase since 199918. Even while excluding spending on tours, for example to the Reef off-shore from Port Douglas, the direct value of tourism to the local economy thus approaches $200 million annually19.

Agriculture is the second most important sector of the local economy. The gross value of production in the Shire for the year ending June 2001 was $11.9 million for crops (principally sugar cane) and $1.1 million for livestock (OESR, 2003).

The estimated resident population for the Shire was 11,525 in June 2003 (OESR, 2004) and grew at a rate of 2.6 % in the preceding 12 months (Table 1.2). The projected population of the Shire in 2026 (under a ‘medium’ growth scenario) is 17,059 (PIFU, 2004). In 2001, the median age was 35 years, while 20 % of the population was under 15 and 8 % were over 65. The projected median age for 2026 is 45 (PIFU, 2004).

The Shire population tends to be poorer but better educated than the Queensland average. Mean taxable income for Douglas Shire in 2000-01 was $29,810, compared to $34,980 for Queensland (OESR, 2004). The percentage of the population over aged 15 with post high school educational qualifications in 2001 was 37.3 % in Douglas Shire and 32.3 % in Queensland (OESR, 2004).

Unemployment in Douglas at the time of the 2001 census was 4.8 %, which was lower than the 8.2 % recorded for Queensland (OESR, 2004). In line with the importance of tourism to the local economy, accommodation, cafes and restaurants were the largest employer in the region, accounting for 21.6 % of the labour force. Employment in the agricultural, forestry and fisheries sector was 6.0 % (OESR, 2004). Of 414 jobs in this sector in the Shire, 168 were associated with sugarcane production, 53 with horticulture, 39 with beef production and 42 with fisheries (ABS, 2001).

17 K. Sherlock (2001). “Port Douglas: The Creative Destruction of a Sense of Place”. TASA 2001 Conference, The University of Sydney, 13-15 December 2001 18 Sustainable Futures report P51. 19 Much of this section has been taken from Smith et al, CSIRO Nov 2004 report.

43 Table 1.2: Demographic data for the Douglas Shire Indicator Value Population, June 2003 11,525 Projected population, 2026 17,059 Annual population growth rate, 2002-2003 2.6 % Age structure, 2001 median age 35 percentage <15 20 % percentage >65 8 %

Projected median age, 2026 45 Mean taxable income, 2000/01 Douglas Shire $ 29,810 Queensland $ 34,980 Percentage of population >15 years Douglas Shire 37.3 % with post high-school Queensland 32.3 % qualifications, 2001 Unemployment, 2001 census Douglas Shire 4.8 % Queensland 8.2 %

44 Chapter 2 Environmental Values and Water Quality Objectives

Summary { Douglas Shire contains parts of two World Heritage Areas – the Wet Tropics and the Great Barrier Reef World Heritage Areas (WHAs). The Environmental Values (EVs) of the freshwaters, estuaries and near-shore waters of Douglas Shire have been established by the Queensland Government, through consultation with the Shire community. These have now been scheduled under an amendment to the Queensland Environmental Protection (Water) Policy 1997. The EVs are the waterway values and uses to be protected for these areas. A census conducted by CSIRO found widespread community support for retention of the natural values of the Shire’s waterways.

{ Total suspended sediments (TSS), and the nutrients - total nitrogen (TN) and total phosphorus (TP) are the three parameters of concern in this WQIP. Water Quality Objectives (WQOs) were established for these parameters to protect the EVs. Subsequent work by QEPA has expanded the WQOs to other parameters and to the whole Shire. These added parameters and waterways have not been included in this plan.

{ Comparison of the WQOs with an ambient water quality monitoring program showed that water quality in the Daintree River and the upper Mossman River meets the water quality objectives for all pollutants of concern. Forms of nitrogen exceed the WQOs in the lower reaches of the Mossman River, while phosphate exceeds the WQO in the lowest reach of the Mossman River and Cassowary Creek. The turbidity WQO is also exceeded in Cassowary Creek. Lower Mowbray exceeded turbidity, total nitrogen and phosphorous. o The principal point sources of the three parameters of concern in this WQIP in the Shire include the sewerage treatment plant at Mossman, unsewered residential areas, tourist resorts, boat discharges (polluter can be isolated, but discharge is diffuse) and aquaculture. Principal diffuse sources include nitrogen losses from sugarcane production, sediment loss from shire’s modified drainage pattern, and streambank erosion. o There has been no long-term monitoring suitable for calculating pollutant loads, (the amount of pollutant eg suspended solids delivered over a period of time). Using CSIRO modelling and expert opinion, TSS, TN and TP loads are estimated to be 134,000 tonnes, 2,250 tonnes and 179 tonnes per annum. Uncleared land, principally in the WHA, is by far the major source of all three pollutants due to the dominant share in area within the catchments. o The same models were used to calculate pre-European settlement loads as 72,800, 1,980 and 122 tonnes p.a. for TSS, TN and TP respectively. These values are used as

45 the interim long-term Aspirational targets for the WQIP. These values will be reviewed with further information generated during the 7-year life of the WQIP.

2.1 Environmental Values Environmental Values (EVs) are defined20 as “the particular values or uses of the environment that are important for a healthy ecosystem or for public benefit, welfare, safety or health and that require protection from the effects of pollution, waste discharges and deposits. Several environmental values may be designated for a specific waterbody.” That is, EVs are the beneficial values and uses that people receive from waterbodies and that need to be protected. These include consumptive uses (such as water for irrigation); non-consumptive uses (such as scenic views across a lake); indirect use values including ecosystems services (such as nutrient removal by wetlands); and non-use values such as bequest values (leaving some values for future generations) and existence values (the benefit from merely knowing that the GBR exists).

The EVs of the freshwaters, estuaries and near-shore waters of Douglas Shire were established using the method established in the National Water Quality Management Strategy (NWQMS) guidelines21. The waterways of the four catchments in the Shire and the coastal waters were grouped into reaches, each judged to possess similar EVs. These are listed in Table 2.1.

Table 2.1: Reaches in the catchments and Coastal Waters sections of Douglas Shire Catchment Water Type Groupings of Reaches Daintree Upland stream Freshwater streams in natural areas Lowland stream Stewart Creek in developed freshwater areas Lowland stream Daintree River in developed freshwater areas Estuary South Arm Reach Estuary Daintree River estuary Saltwater Upland stream Freshwater streams in natural areas Lowland stream Freshwaters in developed areas Estuary Estuarine “saltwater” reaches Mossman Upland stream Freshwater streams in natural areas Upland stream Mowbray River in national parks Lowland stream Freshwaters in developed areas downstream on national parks

Estuary Estuarine “saltwater” reaches Mowbray Upland stream Freshwaters in developed area upstream of national parks Upland stream Mowbray River in national parks

20 Australian and New Zealand Guidelines for Fresh and Marine Water Quality - Volume1. Glossary, Appendix 1. Department of Environment and Heritage, Canberra. 21 Water Quality Targets: A Handbook. Version 1.0 Environment Australia, June 2002

46 Lowland stream Freshwaters in developed areas downstream on national parks

Estuary Estuarine “saltwater” reaches

Coastal Open coastal Inshore (0-5km) coastal Waters (Inshore) Open coastal Offshore (5-20km) coastal (Offshore)

All catchments except the Mowbray have large relatively undisturbed natural areas at their heads. These were delineated as separate reaches. For the Mowbray, a grouping of developed freshwaters reaches was added above the natural reaches. The reaches downstream of these natural areas were grouped into freshwater and saltwater reaches. This allowed the EVs that apply to freshwaters only (e.g. irrigation, stock watering, drinking water) to be separated from those that apply to saltwater. The saltwater reaches on the Daintree were separated into South Arm Reach and the lower Daintree. Finally, the coastal waters were divided into two groups – those within State waters (about 5kms of the coast) and those between 5 and 20kms from the coast.

The EVs for each of these 17 reaches were developed by participants at a workshop in May 200322 and confirmed by the attendees at a subsequent workshop in May 200423. The potential EVs were taken from those identified in the NWQMS (Table 2.2).

Table 2.2: Potential Environmental Values Environmental Value Description Aquatic Ecosystems Supporting pristine or modified aquatic ecosystems High Systems that are largely unmodified or have undergone little conservation/ecological change. They are often found in national parks, conservation value systems (HCV) reserves or inaccessible locations. Targets for these systems aim to maintain no discernable change from this natural condition. Slightly to moderately These systems have undergone some changes but are not disturbed systems (SMD) considered so degraded as to be highly disturbed. Aquatic biological diversity may have been affected to some degree but the natural communities are still largely intact and functioning. An increased level of change in physical, chemical and biological elements of these ecosystems is to be expected. Highly Disturbed (HD) These are degraded systems likely to have lower levels of naturalness. These systems may still retain some ecological or conservation values that require protecting. Targets for these systems are likely to be less stringent and may be aimed at retaining a functional but highly modified ecosystem that supports other environmental values also assigned to it (e.g. primary industries). Primary Industries Irrigating crops such as sugar cane, lucerne, etc. Water for farm use such as fruit packing or milking sheds.

22 Workshop 1 May 16 2003, held at the Douglas Shire Council Chambers. 23 Workshop 2 May 29 2004 held at the Douglas Shire Council Chambers.

47 Stock watering. Water for aquaculture (barramundi, red clay). Human consumption of wild or stocked fish, crustacea. Recreation and Aesthetics Primary Recreation with direct contact with water (swimming, snorkelling). Secondary recreation with indirect contact with water (boating, canoeing). Visual appreciation with no contact (picnicking, bushwalking). Drinking Water Raw drinking water supply. Industrial Uses Water for industrial use (power generation, manufacturing). Cultural and Spiritual Cultural and spiritual values.

Each reach contained a number of EVs, reflecting the values and uses that attendees ascribed to these waterways. The participants at the workshops voted on the degree of protection in the case of aquatic ecosystems, or the level of current use in the case of the other EVs, as described in the NWQMS. There are three possible degrees of protection – high conservation/ecological value (HCV), slightly to moderately disturbed (SMD), highly disturbed (HD) – for aquatic ecosystems, and three levels of current use – high, medium, low – for the other EVs. Thus, the Aquatic Ecosystems in the Stewart Creek reach of the Daintree River were assigned a “slightly to moderately disturbed” degree of protection, reflecting the less than pristine state of these ecosystems. Stock water was assigned a moderate (M) level of use in this river reach.

These EVs and their degrees of protection and current use reflect the special values arising from the presence of the onshore and off-shore national parks and WHAs. Thus, the aquatic ecosystems EV in the streams in WHA at the head of the Daintree River were assigned 100% HCV level of protection, and the aquatic ecosystems in the Coastal Areas beyond 5km offshore were assigned 80% HCV.

2.2 Water Quality Objectives The basis for deriving the water quality objectives for protecting aquatic ecosystems is specified in the NWQMS Guidelines24 “Water quality objectives are measurable outcomes (numerical or narrative values) that, if achieved, should ensure protection and or maintenance of the environmental values. Ideally, the water quality objectives should be based on locally derived data so as to accommodate natural spatial and temporal variations in aquatic ecosystems. Derivation of objectives based on local data may not always be possible. In these situations national water quality guidelines can be used as interim or default water quality objectives while additional information can be gathered to tailor them to local conditions. Where more than one environmental value applies to the same receiving waters, the environmental values need to be prioritised and the most stringent guideline should be used (ANZECC & ARMCANZ (2000a). The most stringent guideline will in many cases also protect the other environmental values”.

24 “The Australian and New Zealand Guidelines for Fresh and Marine Water quality 2000”. ANZECC and ARMCANZ. Environment Australia, Canberra.

48

The Douglas Shire Water Quality Objectives (WQO) on various reaches serve as targets which, if achieved, would protect the EVs that the community would like to see protected. The WQOs should be valued as benchmarks that the shire needs to maintain for healthy waterways.

The Water Quality Objectives (WQOs) in Douglas Shire were established by Queensland QEPA for each EV using both local reference data and the national guidelines.

1. Aquatic Ecosystems (High conservation/ecological value – HCV) For these waterways, the existing water quality (i.e. median and outlying percentile values) was used as the water quality objectives, in accordance with the NWQMS guidelines.

2. Aquatic Ecosystems (Slightly-moderately disturbed – SMD) Locally derived data for waterways of the Wet Tropics was available for reference sites on rivers (upper and lower catchment), estuaries and coastal waters (inshore only). The draft water quality objectives for the SMD Aquatic Ecosystems were derived from this local water quality data. The NWQMS guideline values were used for SMD Aquatic Ecosystems in offshore coastal waters. As specified in the Guidelines, the water quality objective was selected to be the 20th or 80th percentile (whichever was relevant for the particular parameter) of the reference site data for the particular river reach.

3. Aquatic Ecosystems (Highly disturbed – HD) For highly disturbed ecosystems that cannot feasibly be returned to a SMD condition, the Guidelines provide advice to assist managers to derive alternative objectives that give lower levels of protection. In summary, this means firstly assess the existing WQ at the highly disturbed test site. Then, the initial objective is to ensure no deterioration from this. The long- term objective is to attain the SMD objective values.

4. All other environmental values The national water quality guidelines provide default water quality objectives aimed at protecting the other EVs (farm supply, human consumption, etc) which relate to the specific uses of the water.

These water quality guidelines/objectives are presented in Table A.1 (Appendix A) with the footnotes providing further explanation on the refinement of these guidelines/objectives for circumstances in Douglas Shire25.

These WQ guidelines were then considered for each of the EVs in each river reach/coastal area. The most stringent WQ guideline for each pollutant of concern was then selected to be the WQO for that reach (Table A.2 Appendix A). Due to the high environmental values within the Shire, Aquatic Ecosystems was the most stringent WQOs for each waterway section. These WQOs also provide for protection of all other EVs in each waterway section.

25 Queensland EPA. Towards Establishment of Environmental Values and Water Quality Objectives For Douglas Shire Waterways DRAFT - 11 March 2005

49

The Queensland Government has now scheduled these EVs and WQOs under the amended Environmental Protection (Water) Policy 1997: (Environmental Protection (Water) Amendment Policy (No. 1) 2006.

2.3 Pollutants of Concern The EVs cover both fresh and estuarine waters within the Shire and marine waters adjacent to the Shire. The WQIP is concerned with managing the impacts from changes in river flow patterns and reduction in water quality from anthropogenic activities.

Reduction in water quality can affect EVs in a wide variety of ways: • reduction in off-shore habitat, such as sea-grasses and near-shore coral reefs, as a result of blanketing with sediment with consequent losses to recreation and tourism activities; • nutrient enrichment of near-shore waters leading to shifts in species composition and dominance. Nutrient enrichment is (also) thought to affect coral recruitment, which exposes coral to longer lasting damage from events including cyclones, climatic change and crown of thorn-fish; • delivery of toxic material such as pesticides and organic pollutants leading to absorption into the freshwater, estuarine and marine foodchains; • reduction in fish numbers in river reaches affected by low oxygen levels as a result of high BOD levels; and • delivery of pathogens from human and agricultural sources to the nearshore areas.

A range of pollutants has been identified from scientific investigations and during public consultations, including nutrients, sediments, pathogens, agri-chemicals, BOD, and industrial contaminants. However, there is not much information on the concentrations of heavy metals and agricultural chemicals in the Shire rivers, and what little information there is indicates generally low levels of insecticides within the rivers at least. Tests of a range of invertebrate and vertebrate organisms in the Daintree River for heavy metals and agri-chemicals in 199126 found Arsenic, Copper and Zinc at appreciable levels, but very low levels of DDE and Dieldrin. Herbicides including Atrazine appear not to have been tested in this study in the Daintree. However, there was insufficient information given limited resources, to warrant further investigation of these pollutants.

For the WQIP, the main pollutants of concern in the Shire were judged to be nutrients and sediments. These were measured as Total Phosphorus (TP), Total Nitrogen (TN) and Suspended Sediments (SS). These contaminants are released from both point sources (identifiable sites) and diffuse sources (broad area emissions), which are identified later in this chapter.

26 Russell D.J. and Hales P.W. (1993). Downstream effects of agricultural chemicals on aquatic biota – the Johnson River, a case study. In ‘Proceedings, Australian water and Wastewater, 15th Federal Convention”. Gold Coast, Australia. April 1993. pp834-840.

50 Information recently published, Brodie and Mitchell, 2005, indicates that Dissolved Inorganic Nitrogen (DIN) may be the most damaging form of Nitrogen produced for Reef health, and that it is mostly associated with agricultural practices. Dissolved Organic Nitrogen (DON) appears much less likely to be bioavailable in Reef waters. DON is likely to make up the bulk of Nitrogen exported from native forests in the Shire.

2.3.1 Sectoral and Community Attitudes to EVs Consultations were held with industry representatives through three workshops held on May 16th 2003, May 29th 2004 and August 28th 2004 (presentation of shire-wide attitudinal survey to EVs). The feedback from these workshops has been incorporated into the EVs, water quality objectives and management actions described in chapter 4 of this WQIP.

Community attitudes to EVs and WQOs were also tested through a census conducted by CSIRO at all postal addresses in the Shire27. This census confirmed that aquatic ecosystems, aesthetics and drinking water quality were the EVs with the highest rating warranting protection in all catchments and among all groups of land managers. Use of waters for agriculture, aquaculture and recreation were rated with lower importance by all groups. Farmers with >10 ha rated the importance of use of water for irrigation or stock more highly than others, though with less importance than aquatic ecosystems. Cultural and spiritual EVs were rated similarly to agricultural uses for water. Industrial uses for water were consistently rated with low importance.

These results indicate that setting water quality objectives and selecting management actions under the WQIP with reference to aquatic ecosystems, drinking water quality and preservation of landscape character are likely to be widely accepted in the community. Setting objectives with reference, for example, solely to agriculture, recreation or cultural values is more likely to invoke a sceptical response in some parts of the community.

The Shire Council has also established a public website where major documents describing the development of the WQIP and its supporting projects are posted (www.dsc.qld.gov.au).

It is also important to note that the Australian and Queensland Governments have supported inscription of the GBR on the World Heritage List, the GBR has been included in a Marine Park, it is the focus of the joint RWQPP, and that more recently significant public funds have been spent to restructure the commercial fishing sector to enhance the conservation of the GBR. There is therefore strong international, national, regional and

27 DM Smith, PC Roebeling, AJ Webster, M Kragt, I Bohnet, A Zull (2004). Assessment of the Socio- Economic Impacts of Management Options for Improving Water Quality in Douglas Shire. CSIRO Townsville. 27Brodie, J.E. and Mitchell, A.W. (2005). Nutrients in Australian tropical rivers: changes with agricultural development and implications for receiving environments. In Marine and Freshwater Research, (2005) 56, 279-302.

51 local momentum to protect the GBR. Reducing land based sources of pollution to protect these ecological values is consistent with this long-term objective.

2.3.2 Comparison of Current Water Quality and the WQOs Table 2.3 presents the median measured ambient water quality value for each parameter of concern in the Daintree and Mowbray Rivers based on Queensland QEPA water quality monitoring in the Daintree and Mossman Rivers. The Saltwater Creek and Mowbray rivers were not included in the QEPA water quality monitoring, however based on the WQIP community monitoring program these two catchments generally complied (exceeded during wet season) to proposed WQO. The median value is shaded if the water quality objective is not met.

Water quality in the Daintree River and the upper Mossman River meets the draft water quality objectives for all pollutants of concern. Oxidized forms of nitrogen (NOx) exceed the WQOs in the tributaries and lower parts of the Mossman River although TN only exceeds the WQOs in the lowest reaches of the South Mossman River. Phosphate slightly exceeds the WQOs for the lowest reach of the South Mossman River and Cassowary Creek and turbidity exceeds the WQO only in Cassowary Creek. Cassowary Creek has only a narrow band of riparian vegetation lining the lower reaches and the upstream parts of this tributary of the Mossman River are severely disturbed with removal of riparian vegetation. Presumably, the erosion of soils in these areas contribute to the high sediment and phosphate values. The high nitrogen levels in this creek could be due to a number of factors, including runoff from cane fields, seepage from septic systems and animal wastes.

2.3.3 Existing programs addressing pollutants in Douglas Shire There are several projects and programs that assist in reducing these pollutants in the Shire: • the Sugar Research and Development Corporation is funding a project to assess and promote improved management practices in the sugar industry within the Shire. A project officer is located at the Mossman Agricultural Research Station; • the Douglas Shire Council operates a nursery and tree planting program to re- establish trees in critical locations throughout the Shire. CCI funding has upgraded the nursery to increase production; • the grazing industry within the Shire is developing a set of BMPs to reduce the impacts of their industry on the environment; While these BMPs have yet to be finalized or endorsed, they are likely to receive support from the graziers and their industry. • There are a number of Community Based Organisations active in the Shire. The Low Isles Preservation Society has established a program to reduce litter and operational and monitoring programs on Low Isles. Several tree planting groups operates in the shire, with Daintree Cassowary Care Group operating their own nursery. The Douglas Shire Sustainability Group plays an active role to raise the profile of sustainability in this shire.

52

Table 2.3: Median concentrations and WQOs for a range of water quality parameters for the identified reaches of Daintree and Mossman Rivers (Median values in red if they exceed the WQO).

Monitoring Median WQ Values & draft WQ Objectives River/Creek Site TN NOx N Total ammonia N TP PO4 Turbidity Chl a (Distance Median WQO Median WQO Median WQO Median WQO Median WQO Median WQO Median WQO from mouth, km) mg/L NTU μg/L Daintree River System DAINTREE RIVER 32.4 0.131 0.150 0.010 0.030 0.004 0.006 0.010 0.010 0.003 0.005 2.5 6 0.5 0.6 [UP] STEWART CREEK 0.15 0.124 0.240 0.014 0.030 0.005 0.010 0.008 0.010 0.003 0.004 3 15 0.5 1.5 [LOW] DAINTREE RIVER1 12.6 0.142 0.250 0.022 0.030 0.011 0.015 0.013 0.020 0.003 0.005 5.5 10 1.87 3 [Est] DAINTREE RIVER1 8.7 0.134 0.250 0.010 0.030 0.009 0.015 0.013 0.020 0.003 0.005 5 10 1.94 3 [Est] Mossman River System MOSSMAN RIVER 14.35 0.119 0.150 0.019 0.030 0.003 0.006 0.006 0.010 0.004 0.005 0 6 0.5 0.6 [UP] MOSSMAN RIVER 1 7.65 0.177 0.250 0.080 0.030 0.005 0.015 0.007 0.020 0.003 0.005 1 10 0.5 3 [Est] SOUTH MOSSMAN 8.15 0.187 0.240 0.092 0.030 0.005 0.010 0.008 0.010 0.004 0.004 1 15 0.5 1.5 RIVER [LOW] SOUTH MOSSMAN 1.35 0.278 0.240 0.165 0.030 0.008 0.010 0.010 0.010 0.005 0.004 2 15 0.5 1.5 RIVER [LOW] SOUTH MOSSMAN 0.65 0.428 0.240 0.195 0.030 0.028 0.010 0.013 0.010 0.006 0.004 5 15 0.5 1.5 RIVER [LOW] CASSOWARY 1.3 0.714 0.240 0.320 0.030 0.024 0.010 0.037 0.010 0.008 0.004 10 15 0.5 1.5 CREEK [LOW] based on water quality at largely un-impacted reference sites [Water Type] UP = Upland Stream (freshwater) LOW = Lowland Stream (freshwater) Est = Estuary

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2.4 Pollutant Loads

2.4.1 Point Sources of Pollution28 Licensed Environmentally Relevant Activities (ERAs) that are potentially significant point sources of pollution in Douglas Shire are: • Sewage Treatment Plants (STPs); • waste disposal facilities; • aquaculture facilities; • sugar mills; and • extractive industries such as dredging and quarries. The following point sources are listed from most significant to least significant based on their potential contributions to water quality impairment. Other, minor sources of point pollution not specifically discussed here, include motor vehicle workshops, petrol stations and quarries.

Sewage treatment plants The Port Douglas STP is licensed to discharge 5,700 cubic metres per day, except on wet weather days when it must not exceed 28,500 cubic metres per day. The plant discharges to Dickson Inlet. The plant uses biological treatment to achieve reductions in nutrients and suspended solids in sewage effluent that are above the standard achieved in a tertiary treatment plant. The phosphorus is retained in the sludges generated by the process and the nitrogen is discharged to the atmosphere through a process of nitrification and denitrification. Some of the effluent from this plant is supplied for reuse on the Marina Mirage resort golf course.

The Mossman STP is licensed to discharge a maximum of 4.2 t/yr of N, 4.2 t/yr of P and 12.6 t/yr of SS to the Mossman River (1,150 cubic metres per day during dry periods, and a maximum of 5,750 cubic metres per day during a wet weather day). The plant is older than the Port Douglas STP and was designed for disinfection and BOD removal rather than for nutrient removal. However, the operators have modified the operation of their oxidation ditch to consistently achieve good denitrification and some phosphorus removal. There is no reuse of effluent from this plant. The residential area of North Mossman has recently been connected to the Mossman sewage treatment plant, as will Newell and Cooya Beach and potentially Wonga Beach. Feasibility of Wonga Beach being either connected to Mossman STP or being a stand- alone system has not been commenced.

Unsewered residential areas Septic systems and package treatment plants are also utilised for smaller urban populations, rural residential and more remote tourist accommodation facilities. There are currently more than 2,000 unsewered residences on septic tank systems in the project area. The poorly draining clay loam soils found in some of the project area, particularly in the Daintree catchment, may give rise to environmental and health issues due to failures of absorption trenches serving septic tanks. The efficiency of septic systems will be affected by factors such as soil drainage, trench size and rainfall. At the other end of the spectrum, the unsewered settlements on the beaches are

28 This section based on report from Project Three “Control of Point Source Discharges of Sediment and Nutrient In Douglas Shire”, Task Seven, (Anon) “Establish program for upgrading significant point sources of sediment and nutrient discharge.” September 2003. Environmental Protection Agency, Douglas Shire Council

54 Draft Water Quality Improvement Plan typically built on free draining dune structures that allow septic tank effluent to readily contaminate groundwater. Seasonal elevation of these water tables can bring this contaminated ground water to the surface with attendant public health and environmental impacts.

The nutrient loads generated by the unsewered residential areas of Cooya, Newell beach and Craiglie/Wonga are estimated to total about 11.6 t N/yr and 5.5 t P/yr. Not all of this will be discharged to waterways. However, some of these areas have seasonally high watertables and may discharge effluent during wet periods. The Council is currently conducting a survey of watertables in these areas to provide some baseline data on this source of pollution.

Septic tanks on individual rural properties, if sited and maintained properly, confine phosphorus and pathogens to the soil. Nitrogen is discharged to the atmosphere through denitrifying process or taken up in plant material. No survey has been carried out within Douglas Shire of the state of operation of these septic tanks. However, based on experience in other rural areas, it is expected that about 50% are not functioning properly and may be contributing nutrients to nearby creeks during wet periods. However, given the small rural population of the Shire, these contributions are likely to be low and will not be considered further.

Resorts None of the resorts with package treatment plants discharge to surface waters. They all irrigate their effluent to maintain garden beds and lawns around the resorts. Provided that contamination of surface runoff and seepage to groundwater are properly managed, these resorts are unlikely to pose much threat of environmental contamination.

Boat Discharges People living on boats moored in Dickson Inlet or on the Daintree or Mossman Rivers are unlikely to use on-shore waste facilities and are presumed to be discharging directly into the water. These discharges may cause local pollution of pathogens and nutrients where there is little tidal exchange, but are unlikely to make major contributions to pollution of near shore areas. Nevertheless, these discharges can pose localised health and eutrophication risks, as well as being unsightly.

Offshore boat operators at present are permitted to discharge effluent into the GBR lagoon when 1000m from shore or the green zone of reefs.

Aquaculture Aquaculture potentially has a number of impacts on water quality such as discharges leading to increased nutrient, sediment and chemical loads in waterways, release of waters with low dissolved oxygen concentrations, and release of pathogenic organisms.29 Pollution from aquaculture effluent is localised and can vary according to rainfall, farm location/design layout, season, age of ponds, other activities in the catchment and farm management practices.

There are six aquaculture facilities operating within the Shire. Five of them are less than five hectares in size and operate with a Council permit. Council is currently reviewing licence conditions. The only aquaculture facility in the project area licensed by the QEPA is the Seafarm Pty Ltd prawn farm in Dickson Inlet. The operation is licensed to discharge up to 195

29 Productivity Commission. Industries, Land Use and Water Quality in the Great Barrier Reef Catchment . Research Report. www.pc.gov.au/study/gbr/finalreport/ Accessed 01/09/03

55 Draft Water Quality Improvement Plan megalitres per day of wastewaters from prawn ponds to Muddy Creek and Packers Creek, which both drain to Dickson Inlet, with an annual licensed load of 178 t of N, 5.7 t of P, and 2,135 t of SS. Currently, the average annual measured discharges to be 1 t for nitrogen, 0.33 t for phosphorus and 107 t for suspended solids. Although these are much less than the licensed loads, this facility is the single most significant point source in Dickson Inlet.

Sugar Mill The Mossman Central Mill Limited is the only significant source of thermal pollution in the Shire. The Mill is licensed to discharge up to 70 megalitres per day of cooling waters to the South Mossman River with an annual TSS discharge of 383 t. The discharge also contains traces of sugars, commonly measured as BOD (Biochemical Oxygen Demand), and excess condensate. Whilst this effluent generally contains low levels of nutrients, the elevated temperature of the discharge, particularly during periods of very low stream flow, has the potential to increase the impact of nutrients from other sources, such as the Mossman sewage treatment plant located upstream of the mills discharge. Previous discharges from the Mill have lowered the BOD in the South Mossman River causing penalties.

Because thermal pollution is not one of the pollutants of concern it will not be discussed further in this report. However, the QEPA will continue to work with the Mossman Mill to minimise pollutant release occurrences and associated impacts.

Development Sites Responsibility for controlling sediment movement from development sites has recently been passed from QEPA to Council with the delegation of the Environmental Protection (Water) Policy 1997. The majority of building construction occurs during the wet season when tourism demand is low but when the risk of sediment and attached nutrient loss is highest. Consequently, soil losses can be high. Currently, fines are small and little deterrent to poor practice.

Dredging Dredging is used to maintain the channel and access to berths in the Port Douglas Marina and the channel across the Daintree River for the Daintree ferry. The release of sediment in these dredging operations can be minimised by selection of the most appropriate dredging method for the type of sediment being dredged and placement of the spoil on land or at a location where they are unlikely to re-enter Shire waterways.

In-river dredging is also used for prevention of a sand-bar at the Daintree River ferry crossing and for commercial purposes in Saltwater Creek under permits from the QEPA and QNR&M. Illegal dredging of streams is believed to occur at times. These sediment loads released from these operations are difficult to estimate and unlikely to be large compared to other sources of sediment. They will not be considered further in this Plan.

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Quarrying Extractive operations over 5,000 cm3 are Environmentally Relevant Activities and require licences from QEPA. They are required to comply with erosion guidelines and are subject to self-regulation with regular reporting. Smaller extractive operations require permits from the Council. There are three quarries in the Shire licensed by the QEPA and eleven with Council permits.

2.4.2 Diffuse sources30 Nutrients A wide range of broadscale land uses contribute diffuse source nutrients to waterways. In the Douglas Shire, the principal diffuse sources are natural and plantation forests (including in the WHA and National Parks), non-irrigated agriculture (grazing and sugar), horticulture, and rural residential activities.

Nutrients also enter directly into waterways from atmospheric deposition. About 0.2 g/m2 TN and 0.0115 g/ m2 TP of atmospheric input were measured offshore in the Cairns region31 during rainfall events. Dry deposition of TP was estimated to be between 20-40% of wet deposition; dry deposition of TN was not measured. Most atmospheric deposition of N and P over the catchments of Douglas Shire would eventually be incorporated into the runoff from catchment surfaces. The only additional input would be the nutrients that fell directly onto the surfaces of the Shire’s waterbodies. Assuming an open water area of 107 m2 within the Shire, annual direct atmospheric deposition is estimated to be approximately 3 tonnes TN and 0.15 tonnes TP if the offshore deposition rates also apply to onshore deposition. These contributions are small enough to be ignored.

Sediments Sediments primarily arise from erosion of surface and sub-surface soils and from erosion of stream and drain banks. Apart from causing environmental problems directly, sediments act as carriers for other contaminants such as nutrients (particularly phosphorus), pathogens and toxicants.

The very high rainfall regime, together with the steep slopes and areas of erosive soils means that high erosion rates are a feature in both the natural and disturbed landscapes. Although forested areas generally are more absorptive of rainfall, overland flow has been demonstrated during monsoon and post-monsoon storms in an undisturbed rainforest catchment near Babinda. This overland flow would result in significant sheet erosion. This, coupled with the large areas of the Shire occupied by forest implies that vegetated areas can be a significant source of sediment, even in undeveloped areas such as national parks. The loss of sediment can be significantly increased if the area possesses unsealed tracks and roads that erode in heavy rainfall. Feral pigs and cattle in the upper Daintree catchment are also believed to add to soil loss because of their disturbance of ground cover.

30 R Bartley, A. Henderson, G. Baker, M. Smith, T. Webster, A. Rudd (2004). Identifying critical sources and sediments and nutrients in the Douglas Shire Catchments (Daintree, Saltwater, Mossman and Mowbray Catchment) North Queensland. CSIRO Land and Water report to Environment Australia. 31 Miles Furnas, Alan W. Mitchell and Michele Skuza (1995). “Nitrogen and Phosphorus Budgets for the Central Great Barrier Reef Shelf”. Research Publication 36, Great Barrier Reef Marine Park Authority, Townsville, Queensland.

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Loss of vegetation in grazing and sugar cane areas can result in even higher erosion rates especially if the stream bank vegetation is removed. Annual erosion rates of 150 t/ha have been measured in sloping cane land under conventional cultivation. However, this rate has been reduced to 15-20 t/ha with green cane harvesting and minimum tillage. Nearly all cane growers in the Douglas Shire practice greencane harvesting. Vegetated riparian strips are well known to be able to intercept and store sediments from surface erosion32. However, many of the grazing properties in the upper Daintree catchment have been cleared to the stream edges and potentially provide a direct delivery pathway for sediments.

Stream bank disturbance itself can contribute large quantities of sediment to downstream areas as even small catchment areas produce high stream discharges. Streambank erosion is notable in some of the Shire’s rivers such as Stewart’s Creek, and can be exacerbated by in-river activities such as frequent boat travel as can be witnessed on the Daintree River.

Not all eroded sediments are transported directly to estuaries and near-shore areas. During high flow events, a considerable portion of the sediments is deposited on floodplains from which it can be eroded and transported further downstream by subsequent floods. Mangroves in the tidal portions of the Shire’s rivers also trap considerable quantities of sediments and attached nutrients.

2.4.3 Current Pollutant Loads Pollutant loads in the rivers of the Shire can be calculated from knowledge of the flows in the rivers and the concentrations of the pollutants at various flow sizes. The concentrations vary considerably with the time of year and the size of flow event. The largest fraction of pollutant loads are moved during high flow events, and so these events should be sampled more intensively to increase the reliability of load estimates. Unfortunately, the limited amount of water quality data collected from Shire rivers has not been suited to calculation of pollutant loads, until the introduction of the CCI programme.

2.4.4 Loads from Monitoring The Queensland Department of Natural Resources, Mines and Water operates three water quality and four river flow stations in the Daintree catchment and one flow and water quality station in the Mossman catchment. The Queensland QEPA operated water quality monitoring sites on the Daintree and Mossman Rivers during the period 1994 –1999 to monitor ambient water quality.

The only data suitable for calculating pollutant loads comes from monitoring conducted as part of the preparation studies for this WQIP. The CSIRO installed automatic sampling stations, triggered to record flows and water quality during flow events of all sizes, at the upper and lower Daintree and Mossman Rivers and the lower Saltwater Creek. Because of difficulties in estimating flows at the three lower stations, load estimates could only be made for the two stations at the upper Daintree (Baird’s Crossing) and upper Mossman (below Mossman Gorge) Rivers. Table 2.4 provides the estimated loads for the 7-month period from 1/12/03 to 30/8/04. Since this period spans the wet season, the load estimates are close to the annual loads for that year.

32 Price, P. and Lovett, S. 2002, ‘Improving water quality’, Fact Sheet 3, Land & Water Australia, Canberra.

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The absolute values of the monitored pollutant loads are subject to errors for two general reasons. First, only a single season (7 months) was monitored and there were large gaps in the record. The 2003-04 year was significantly wetter than average and consequently the load estimates are believed to be higher than a ‘typical’ year. Secondly, the loads need to be calculated from the sample data. These calculations require assumptions about the relationship between flow and pollutant concentration and these assumptions introduce further errors into the load estimates. Taking all into account, the CSIRO ascribes an uncertainty of 300-500% to the upper Daintree monitored loads and 200-300% to the upper Mossman monitored loads.

2.4.5 Loads from Modelling Because there is insufficient monitoring data to provide a direct estimate of diffuse source loads in the Shire, the CSIRO SedNet and EMSS models (Appendix B) were used to provide estimates of the pollutant loads33.

The modelled load values can be assessed by comparing them with the monitored loads from the CSIRO automatic monitoring stations for the upper Daintree and upper Mossman rivers (Table 2.6). While there is general agreement between the monitored and modelled loads for the upper Mossman River (keeping in mind the wetness of 2003-04), there are large differences between the modelled and monitored loads in the upper Daintree catchment with large uncertainty factors for both processes. Several explanations are given below to explain these uncertainty factors; Monitoring • interpretation from only one wet season; • less samples collected compared to the Mossman Catchment; • insufficient flow information; and • above average wet season (2003/04) that preceded two below average wet seasons. Modelling • uncertainty in calibration of the flow and event mean concentration (emc) components of EMSS; • the pollutant concentration allows for reliable estimates of emc, therefore emc for natural forests were calculated from Mossman National Park area (rainforest), which is likely to underestimate the emc from Daintree National Park that consists of rainforest and sclerophyll; • SedNet not calibrated locally; and • EMSS and SedNet may not represent nitrogen transport in forested systems well.

The CSIRO concluded that the EMSS model (used for estimating loads from the National Park areas) underestimated loads from this mixed sclerophyll and rainforest regions of the National Parks. They also assigned large errors to the modelled sediment and nutrient loads in Douglas Shire, partly because of the lack of data for calibrating the models and partly because the models used have not been specifically developed for the spatial scale required for this work and the processes occurring in the wet tropics. They estimated the errors in the modelled load values to be ±200% (Appendix B).

33 Tim Ellis, Rebecca Bartley, Joel Rahman, Tony Weber, Anne Henderson, Charles Magee, Jenet Austin, Peter Hairsine, Sam Davies, Sue Cuddy and Jake Macmullin. “Application of two water quality models as a Decision Support System (DSS) within the Douglas Shire. A Report to the Douglas Shire Council and the Department of the Environment and Heritage, Milestones 5.5, 5.10 and 5.15”. CSIRO Client Report, CSIRO Land and Water, Canberra.

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Table 2.4: Discharge and pollutant loads of TN, TP and TSS at Upper Mossman and Upper Daintree from monitoring and modelling studies. Discharge TSS TN TP (ML) (tonnes) (tonnes) (tonnes) Monitored Modelled Monitored Modelled Monitored Modelled Upper 1,530,000 225,200 21,300 3,500 1,050 240 36 Daintree Upper 280,895 2,900 2,000 150 100 5 3 Mossman

In spite of these large uncertainties, the CSIRO models were used to estimate the pollutant loads under present day conditions because actual monitored loads are not available at the ends of the four river catchments. These loads are shown in Table 2.5. The details of the modelling calculations are contained in Appendix B. As monitoring information improves and model calibration is enhanced more accurate water quality and management action target settings will be made.

As a result of these significant uncertainties, a conservative approach has been adopted to identifying and implementing management actions, consistent with the precautionary principle. Consequently eco-efficiency measures (i.e. measures that are financially beneficial to the enterprise and reduce environmental impact) that assist in minimising nutrient loss to waterways, and reducing the loss of soil from cane drains, take a high priority.

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Table 2.5: The loads of pollutants of concern in the four catchments in Douglas Shire. Diffuse loads were obtained from CSIRO modelling studies and are subject to large errors. Point source loads were taken from Appendix G of Final CSIRO Modelling report 2004 - 2005. The negative value for sediment loads in the Mossman estuarine region denotes there is more sediment deposited than eroded in this region. Modelled Pollutant Load (t/yr) TSS TN TP

Daintree River Streams in National Parks Diffuse Sources 21,359 1,052 36 Stewart Creek Diffuse Sources1 13,700 266 16.0 Upper Daintree – WHA to Stewart Ck confluence Point Source Daintree village - 1.0 0.5 Diffuse Sources 8,430 193 11.5 South Arm Reach Diffuse Sources 2,600 30 5 Stewart Ck to Daintree mouth Point Sources Dredging at ferry Unknown - - Moored boats - 0.1 - Diffuse Sources 14,645 150 30

Saltwater Creek Streams in National Parks Diffuse Sources 1,962 60 3 Developed Freshwater Reaches Point Source Miallo - 0.8 0.4 Diffuse sources 14,755 89 15 Estuarine saltwater reaches Diffuse Sources 3,610 40 5

Mossman River Streams in National Parks Diffuse Sources 2,047 97 3.3 Developed Freshwater Reaches Point Sources Mossman STP - 1.6 0.9 Unsewered residential - Unknown Unknown Quarry Unknown - -

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Diffuse Sources 23,275 90 10 Estuarine saltwater reaches Diffuse sources -6,845 10 5

Mowbray River Streams in National Parks Diffuse sources 1,931 34 1.9 Developed freshwater reaches Diffuse sources 1,190 5 0.8 Estuarine saltwater reaches Diffuse sources 680 3 0.1

Coastal region Point Sources Port Douglas STP - 0.2 0.9 Moored boats - 0.3 - Craiglie/Wonga - 17.1 7.9 Newell Beach - 2.8 1.3 Cooya - 3.8 1.8 Aquaculture (Seafarm) 107 1.0 0.3 Diffuse sources 30,578 110 23

TOTAL 134,024 2,258 179 1: Stewart Creek includes streambank erosion contributions from expert estimation.

The diffuse source loads for lowland catchments do not include streambank erosion because of model limitations. The gross streambank erosion in Stewart Creek (Daintree Catchment) was estimated to be 1,600 – 1,900 tonnes of sediment per year by an water-course engineer skilled in riparian management who ground-truthed this creek. The proportion of coarse sediment getting to the estuary within the Daintree Catchment is estimated to be 11% using the SedNet model (Bartley, et al, 2004). The remainder remains stored within the stored stream network and floodplain deposition. The TN and TP fractions of these sediment loads (coarse and fine sediments) are estimated to be 0.1% and 0.025% respectively, giving loads of 1.6 – 1.9 tonnes TN per year and is 0.4 – 0.5 tonnes TP per year (Webster, pers com). These loads have been included in Table 2.7. Loads are not available for streambank erosion from other streams.

Table 2.6 shows that the largest contributions come from diffuse sources for all pollutants (100% TSS; 98% TN; 93% TP). Of these diffuse sources, the largest fractions come from uncleared land (93%, 80%, and 86% respectively) because it is both the dominant land use in the Shire in areal terms and it occurs in the more erosion-prone, higher rainfall country. The major diffuse source contributions from cleared land come from sugarcane, grazing and rural residential land uses (Table 2.6) 34. Of the contributions from cleared land, grazing and sugarcane contribute roughly equal percentages of TSS and TP, while sugar cane is the largest contributor of TN.

34 These percentages were provided in earlier model runs and were not available in the final report.

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Table 2.6: Percentage contributions to the cleared land diffuse source loads from the three principal land uses. TSS TN TP Sugar cane 37 69 47 Grazing 48 24 43 Rural residential 7 5 6

The coastal region, which drains directly into the GBR lagoon, is the region within the Shire that contributes the largest load of sediment, primarily from diffuse agricultural sources. All reaches of the Daintree River, except South Arm, contribute large TN loads, while the largest TP loads come from the National Park and Stewart Creek-to Daintree-mouth regions of the Daintree River and the coastal region.

The effluent from the unsewered villages of Craiglie, Wonga, Newell Beach, and Cooya in the coastal region are the largest point source contributors of nutrients, although these contributions are much smaller than those coming from diffuse sources.

2.4.6 Seasonal variation in loads The effluent loads from the two sewage treatment plants (STPs), unsewered residential areas, resorts, moored boats, aquaculture, and dredging are roughly constant all year round. The diffuse sources are driven by rainfall and so primarily discharge during the wet season. The monitoring by CSIRO in the Daintree and Mossman rivers during the preparation of this Plan showed that a high proportion of the suspended sediment load is move during the wet season. Thus, about 48% of that year’s total annual suspended sediment load was moved during March alone. Although the concentrations of nutrients and sediments peak early in the wet season, the proportion of total load moved is still greater during the later part of the wet season when prolonged monsoonal events and tropical depressions result in high discharges.

2.5 Pre-1850 Pollutant Loads The approach adopted in this plan was to base target loads on estimates of pre-European settlement loads. The pre-1850 loads were estimated using the CSIRO SEDNET and EMSS models (Appendix B)35. The models were run with conditions as close to pre-European values as possible. Specifically: • pre-European coastal vegetation patterns were simulated by replacing sugar cane and pasture with native vegetation; • point source contributions were removed; • all streams were assumed to possess 95% riparian vegetation cover; and • the effects of cane-drains were removed from the models.

The decision on whether to locate Melaleuca/ transitional, rainforest or coastal mosaic (which represents a mixture of mangrove/Melaleuca) vegetation on a particular parcel of land depended on the position of the parcel in the catchment. Soil type, slope and local knowledge from researchers that had worked in the area were used to make these assignments36.

35 CSIRO Revised pre-1850 loads, March 2005. 36 The Queensland Herbarium Pre-European vegetation data set was checked but found not to cover this area.

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The estimated loads of sediment and nutrients in pre-1850 conditions and current loads, together with the percentage change since pre-1850 times, are given in Table 2.7. These estimates are subject to the large errors described in the previous section.

Table 2.7: Contributions of each catchment to pollutant loads in pre-European conditions and current day. SEDIMENT Total Sediment (‘000 tonnes/annum) % Increase Pre-1850 Current Increase Daintree 50.5 57.2 6.7 13 Saltwater 7.8 20.3 12.5 160 Mossman 6.2 18.5 12.3 198 Mowbray 2.4 3.8 1.4 58 Coastal 5.9 30.7 24.8 420 Shire 72.8 134.0 61.2 84 NITROGEN Total Nitrogen (tonnes/annum) % Increase Pre-1850 Current Increase Daintree 1,630 1,690 70 4 Saltwater 121 190 69 57 Mossman 135 199 64 47 Mowbray 38 42 4 11 Coastal 58 135 77 133 Shire 1,980 2,258 278 14 PHOSPHORUS Total Phosphorus (tonnes/annum) % Increase Pre-1850 Current Increase Daintree 90 99 9 10 Saltwater 13 23 10 77 Mossman 7 19 12 171 Mowbray 2 3 1 50 Coastal 10 35 25 250 Shire 122 179 57 47

Note: pre-1850 loads estimated from CSIRO modelling; current day loads (Table 2.7) taken from CSIRO modelling, estimates based on expert opinion, and monitored loads from point sources.

The CSIRO modelling shows that, overall, there has been an increase of 84% and 47% in sediment and total phosphorus loads respectively since pre-European times. The increase in total nitrogen loads is much less at 14%. About 40% of the additional 61,200 tonnes of sediment and 57 tonnes of phosphorus have come from the coastal strip (25,000 tonnes TSS p.a. and 25 tonnes TP p.a.) although the loads in the Mossman and Saltwater catchments have also increased significantly since pre-1850 times.

Although the absolute errors in these estimates of the pre-1850 and current day loads are very large (200-300%), the errors in the differences between the pre-1850 and current day loads are likely to be smaller because the errors are systematic. That is, if the pre-1850 TP load is over- estimated by, say 100%, then the current day load will also be over-estimated by a similar amount because the same model was used for both estimates. However, the sizes of these relative errors in the “% change” columns of Table 2.7 are not known.

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2.5.1 Total Maximum Pollutant Load Targets

Target loads should be set so as to protect the receiving waters – in the case of Douglas Shire, the Great Barrier Reef system, including the lagoon. However, the links between pollutant loads from the coastal rivers and the impact on the Reef system are poorly understood, and thus setting load targets based upon a precise knowledge of what the system can tolerate is not yet possible.

It is never the less accepted that an Aspirational goal should be set to allow protection of the Great Barrier Reef, and thus an Aspirational target has been set of the estimated loads of pollutants present before European settlement of the Douglas Shire.

However, this target (while an estimate and therefore itself subject to revision) is plainly not realistic. Monitoring and modelling have provided an estimate of the human-induced (anthropogenic) loads of sediment and nutrient exported to Reef waters. To ensure the retention of the Environmental Values of the Great Barrier Reef, the goal has been set of reducing these loads by half. This equates to a Total Maximum Pollutant Load, and becomes a Resource Condition Target, which will be revised as more data is acquired.

It is recognised that reaching this goal presents great challenges to the community of Douglas Shire, and thus a time frame of 25 years has been set. It is also recognised that there is considerable uncertainty in these targets because of the uncertainties associated with estimations provided by modelling. This means that the target values should be modified during the life of the WQIP as better information becomes available from monitoring and advances in modelling in wet tropical regions of Australia.

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Chapter 3 River Flow Objectives

Summary o Aquatic life and protection of the environmental values in the rivers and estuaries of Douglas Shire depends on the continuation of long term flow patterns as well as good water quality. o Flow patterns can be modified through impoundments across rivers, extractions of water, discharges of water and changes in land use. Climate change will also affect rainfall patterns as well as evaporation characteristics. o There are no impoundments across Shire rivers, and none are planned. o There are some small irrigation and town water supply withdrawals under licence to the Queensland Department of Natural Resources. The irrigation extractions may have local effects; water supply to Mossman and Port Douglas does not appear to constitute a major component of river flows. o There have been major changes to the land use that have altered runoff patterns in the Shire lowlands. The CSIRO modelling shows that 87% of runoff originates in the high rainfall coastal ranges where vegetation has been relatively undisturbed. The land use changes may have altered the pattern of runoff in the lowlands. o The volumes and patterns of flows in the rivers are not believed to have changed significantly since pre-European times although there may be some changes in the Shire lowlands as a result of changes in land use. o The Douglas Shire council and the Queensland Department of Natural Resources and Water have drafted a MoU containing draft flow objectives. This Plan recommends the following objectives, consistent with the MoU: • Maintain current flow volumes • Maintain both inter-annual and intra-annual natural flow variability, • Prevent barriers to wetland and floodplain inundation • Minimise effects of weirs and other barriers across rivers • Minimise effects of dams on water flows • Minimise drainage to rivers and estuaries through BMPs and recycling • Minimise water withdrawals from rivers • Maintain in-stream river and estuarine physical habitats

This will be consistent to a Wet Tropics Water Resource Plan that is planned to commence in 2008.

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3.1 Environmental Water Needs Aquatic life in the rivers of the Shire and in the estuarine areas depends on both good water quality and the continuation of long term flow patterns. While the remainder of this report deals with water quality, this chapter assesses the maintenance of flow volumes and flow patterns in the Shire rivers.

The rivers in Douglas Shire are highly seasonal with peak flows being experienced during the December-April wet season. There is also considerable inter-annual variability in the flows, as illustrated by the monthly flow volume at Baird’s Crossing on the Daintree River (Figure 3.1). While there is not such an extensive record of flows available for Saltwater Creek, Mossman River and Mowbray River, the available records indicate a similar pattern of inter-annual and intra-annual flow variability.

NR&M WaterShed HYPLOT V112 Output 29/01/2004 Period 36 Year Plot Start 00:00_01/10/1968 1968-04 Interval 1 Month Plot End 00:00_01/10/2004 1 108002A Daintree_R Bairds 151.00 Total Volume Ml 108002A 2000000

1600000

1200000

800000

400000

0 1 1968-77 1978-87 1988-97

Figure 3.1. Monthly aggregate flow at Bairds Crossing, Daintree River (Source: Qld NR&M)

3.1.1 Role of flows River flows play multiple important roles in maintaining the health of rivers and estuaries and supporting human activities that depend on the productivity of these rivers and estuaries. The transport of sediments down rivers, particularly during high flows, helps maintain physical substrate characteristics (eg. gravel bed, sand bed, mud bed), provides snags and other physical habitat, maintains channel morphology, and provides material (including nutrients) for floodplains and estuaries. High flows can erode both river banks and estuarine channels maintaining them in the face of steady depositional buildups. Water availability is also the primary control over riparian, floodplain and estuarine vegetation. Flows not only provide water but also provide nutrients and substrate and, in the case of floodplains, can transport biological

67 Draft Water Quality Improvement Plan material back into the river. Freshwater fish depend on river flows for food, habitat and, in some cases, for breeding cues. Estuarine fish species also appear dependent on freshwater flows with good empirical evidence from the Fitzroy River that the size of the year class in Barramundi caught in that estuary depends on the size of the corresponding spring and summer freshwater flows into the estuary37. There is similar evidence for a relationship between prawn catches and the occurrence of freshwater flows in estuaries around Australia, including Queensland. Thus, catches of banana prawns in the Gulf38 and King prawns in the Fitzroy estuary39 have been positively correlated with high river flows. The presence of nuisance species of plants and animals can also be minimised through the maintenance of a natural flow regime to which these invasive species may be poorly adapted.

Although a solid body of scientific literature has been built up in temperate Australia, especially in the Murray-Darling basin, detailing these links between river flows and ecological responses, there has been a dearth of such studies in tropical Australia. None have been conducted in the rivers of Douglas Shire, although there is a study by CSIRO40 and Earthwatch presently underway in the Daintree, Mossman and Saltwater Creek catchments to quantify linkages between Wet Tropics riparian systems and in-stream health including habitat condition, distribution and abundance in-stream flora and fauna, and ecological processes. The Barron River Water Resource Plan41 provides more detail on the contributions of different components of the hydrograph to maintaining suitable environmental conditions for geomorphology, aquatic and riparian vegetation, invertebrates, fish, reptiles and birds. A study is also available for the Burnett Basin Water Allocation Management Plan42. Although comparable studies have not been undertaken in Douglas Shire, the dependence of these organisms on different flow components can be expected to be similar.

In addition to these scientific studies, a small number of environmental flow studies have been conducted in Far North Queensland as part of water allocation processes. Both the Tully- Millstream Hydroelectric Scheme and the water harvesting proposal for Behana Creek, a tributary of the Mulgrave River, included assessments of environmental flow needs but both reports have been commissioned by private industry and neither is publicly available. The Water Resource Plan has been completed for the Barron River and an operational plan is being prepared. An environmental water assessment was included in the planning process43. This assessment was based on expected changes to river flows and river levels for three scenarios and

37 Staunton-Smith, J., J. Robins, D.G. Mayer, M.J. Sellin, I.A. Halliday (2004). Does the quantity and timing of fresh water flowing into a dry tropical estuary affect year-class strength of barramundi (Lates calcarifer)? Marine and Freshwater Research 55 787-797. 38 Loneragan, N.R. and Bunn, S.E. (1999). River flows and estuarine ecosystems: implications for coastal fisheries. Australian Journal of Ecology 24, 431-440 39 Platten, J.R. (1996). The influence of Fitzroy River freshwater discharge on fishery catch rates in central Queensland waters. Unpublished report to the Department of Natural Resources, Queensland. 14 pp. 40 Dr Frederieke Kroon “Effectiveness of riparian restoration in improving stream health in tropical North Queensland”. Project proposal. 41 Department of Natural Resources and Mines, 2001. Barron water resource plan: Environmental investigations report. Queensland. Department of Natural Resources, Mines and Water, Brisbane. 42 Arthington, A.H., Brizga, S.O., Bunn, S.E. and Loneragan, N.R. (2000) Estuarine and Marine Ecosystems. Burnett Basin WAMP, Current Environmental Conditions and Impacts of Existing Water Resource Development, Queensland Department Natural Resources, Brisbane. 43 Department of Natural Resources and Mines, 2001. Barron water resource plan: Ecological implications report. Queensland. Department of Natural Resources, Mines and Water, Brisbane.

68 Draft Water Quality Improvement Plan the likely geomorphological and ecological implications of these changes based on expert judgements and limited physical data.

3.1.2 Development Effects on Flow Flow regimes can be modified in four ways. 1. Impoundments (such as dams) and barriers (such as weirs and locks) change the flow pattern, often reducing medium sized floods and augmenting flows during dry periods. When the barrier is placed near the mouth of the river, as occurs on the Fitzroy River, it can prevent the intrusion of saltwater upstream during periods of high tide or low river flow. 2. Direct extractions for irrigation and town supply reduce the total volume of flow, particularly during dry periods. 3. Water discharges from agricultural drainage, effluent and stormwater also affect the flow patterns often increasing dry season flows (they also usually introduce pollutants, including thermal pollution). 4. Changes in catchment land use affect rainfall-runoff relationships. Generally, total flow volumes are increased when forest cover is replaced by agriculture or horticulture because grasses and shrubs have lower evapo-transpiration than trees, thus making more water available as runoff to rivers44. Land use change also affects the pattern of flows. Conversion of forest to agriculture generally causes river flows to be peakier during floods because runoff is not retarded as much by agriculture and horticulture; and flows during low flow periods can be augmented because of the reduced evapo-transpiration. Lowland and estuarine wetlands and floodplains also remove peaks from flows by allowing floodwaters to spread, which in turn reduces velocity allowing sediment and nutrients to deposit on the floodplain. Conversion of these areas to agriculture with associated flood protection works cause floods to remain more intense. Lowlands that provide or provided the role of sinks that reduced the intensity of floods need identification. Existing wetlands need assessment of their functionality during floods, and lowlands that have been converted to agriculture need to be assessed for reinstating their function during flooding. Prior to any potential development, investigation of these effects is clearly vital.

Climate change from global warming can also affect water availability, although the particular effects depend on the region. In general, Australia is predicted to experience a decrease in precipitation although this may not be true for tropical regions; this effect is not examined here because of the limited information available, and that the lack of impoundments in the Shire mean there is no practical response to the need to increase flows should climate change realise reduced flows.

The above four influences on flow quantities and patterns are examined for Douglas Shire in the following section.

3.1.3 Modifications to Flow Impoundments. There are no impoundments or barriers on the rivers of the Shire. At present there are no plans for dams or other infrastructure on the rivers of the Shire45.

44 Zhang, L., W. Dawes, G. Walker (1999). Predicting the effect of vegetation changes on catchment average water balance. CRC Catchment Hydrology. Tech Report 99/12. 45 Information provided by DNR&M to DSC.

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River extractions. There are some small irrigation and town water supply withdrawals taken directly from the rivers under licence to the Queensland Department of Natural Resources and Water. The largest of these is for urban supply to Mossman, Port Douglas, and Craiglie from Rex Creek. Water for Wonga, Miallo and some cane farms is withdrawn from Little Falls Creek and water for the village of Daintree is withdrawn from Intake Creek. These withdrawals are a small fraction of the flows in these rivers, even during the dry season (Table 3.1). These are monthly total flow and extraction data – it is possible that, on a day-to-day basis these urban water supply extractions could be more hydrologically significant.

There are no data available about the hydrological or ecological effects of irrigation extractions in the Shire. Observations indicate that, although individual irrigation extractions are relatively small, the cumulative effect of number of extractions on a small tributary streams could be significant during the dry season. DNRW will introduce metering for ground and surface water extraction and is expected to be completed by 2013.

Table 3.1: Water withdrawal rates from the three points of urban supply in Douglas Shire. Month Rex Creek Percentage of Little Falls Intake Creek Mossman Pt Rex Creek flow Creek Daintree1 Douglas (%) Whyanbeel Craiglie (Saltwater) December 2004 386 ML 1.5 49 ML 5.7 ML November 440 ML 1.3 48 ML 5.7 ML October 465 ML 1.2 69 ML 5.7 ML September 422 ML 1.4 49 ML 5.7 ML August 430 ML 1.3 58 ML 5.7 ML July 446 ML 1.3 37 ML 5.7 ML June 322 ML 1.8 33 ML 5.7 ML May 300 ML 1.7 29 ML 5.7 ML April 290 ML 1.7 25 ML 5.7 ML March 265 ML 2.2 26 ML 5.7 ML February 262 ML 2.2 24 ML 5.7 ML January 300 ML 1.9 26 ML 5.7 ML 1 Constant flow to reservoir

Council has agreed to expand sewerage coverage in Mossman and surrounding villages. This will place additional pressure on water extractions from Rex Creek, however DSC will not be seeking an increase in extraction from DNRW. There are also no plans for additional water extraction for Port Douglas. There may be a demand for additional irrigation extraction licences if there is an increase in horticulture in the Shire. These licences should be examined for their cumulative effects, particularly if they are on smaller tributary streams.

Discharges. The Shire’s rivers receive drainage from cane fields and cattle properties, effluent from town sewage treatment plants and industry (primarily the Mossman sugar mill), and urban runoff. While these flows carry pollutants (dealt with in the next chapter) they are not of sufficient size to affect river flows substantially.

Changes in Land Use. There has been considerable conversion of lowlands to sugar cane throughout the Shire and approximately 5,700 ha mid-slope country to grazing (Table 1.1).

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Under agriculture these lands may provide more runoff than when they were forested. However, the CSIRO modelling of current conditions shows that at least 87% of river flow originates in the high-rainfall areas of the coastal ranges which largely remain under rainforest (63% of Shire) and sclerophyll forest (24% of Shire)46.

These source areas lie largely within the WHA and are protected from development. In the absence of major climate effects, the flow quantities and patterns from these areas are unlikely to change. The lowland areas, currently under sugar cane, will necessarily change to other land uses if the sugar industry fails in the Shire. This conversion would lead to a decrease in drainage to the rivers and estuaries. The most likely replacement land uses are increased small acre allotments, grazing on viable sized allotments and diverse horticultural activities. While the former is unlikely to lead to a substantial change in extractions or discharges to the rivers, the latter may draw more heavily on groundwater or river sources and thereby affect river flows during low flow periods. However, there is little information on either the likelihood of these changes occurring or their effect on river flows.

Given the absence of impoundments and barriers to flow on the rivers in the Shire; the small extractions from the rivers compared to the size of flows in the larger tributaries and rivers; the limited volumetric discharges back to the rivers; and the retention of the majority of the Shire’s catchments (87%) under forest cover, it is reasonable to assume that the flows in the four major rivers of the Shire have not been substantially modified since European settlement.

The absence of plans for impoundments or barriers on the Shire’s rivers; the limited planned increase in water extraction for urban purposes; and the protection of the source areas under WHAs mean that the river flows are likely to remain close to their natural quantities and patterns during the life of this plan.

3.1.4 Environmental Flow Programs There are no programs to manage river flows for the benefit of the riverine or estuarine environments in Douglas Shire at present, and no Water Resources Plan has been scheduled for the Shire’s rivers. In the absence of a WRP, the Council and DNRW have drafted a MoU which contains draft environmental flow objectives.

However, the Wet Tropics Regional WRM Plan includes two targets for environmental flows that, in principle, apply to the Shire: • W1.1 Establish monitoring programs and report on environmental flow conditions within the region’s waterways by 2008; and • W1.2 Rehabilitate all structures negatively affecting environmental flows by 2015. The first target will be partially met through the existing DNRW flow monitoring program and the flow and water quality monitoring program being established as part of this WQIP will establish the physical flow conditions in the Shire’s rivers. However, given the very limited ecological information available in northern Queensland, it will need to be augmented with a research program into the dependence of the riverine and estuarine ecology on flows if environmental flow conditions are to be assessed in 2008. In the absence of structures on the Shire’s rivers and the absence of plans to construct them, the second target does not apply in Douglas Shire.

46 CSIRO Modelling report and pers comm. Tim Ellis 4/4/05

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3.2 Flow Management Objectives While the above analysis shows that the flows of rivers in the Shire are still largely natural and that there are no current plans that will change these flows, this prognosis would need to be re- examined if there was a major shift in land use within the Shire such as an increase in irrigation or if developments were proposed that led to barriers across the Shire rivers.

The following set of environmental flow objectives (consistent with the draft DSC-DNRW MoU) will protect the riverine and estuarine environments: ƒ As far as possible, maintain current flow volumes ƒ As far as possible, maintain both inter-annual and intra-annual natural flow variability, ƒ Prevent barriers to wetland and floodplain inundation ƒ Minimise effects of weirs and other barriers across rivers ƒ Minimise effects of dams on water flows ƒ Minimise drainage to rivers and estuaries through BMPs and recycling ƒ Minimise water withdrawals from rivers ƒ Maintain in-stream river and estuarine physical habitats These objectives will need to be implemented jointly with any river development objectives and further expanded with the proposed Wet Tropics Water Resource Plan to commence in 2008 by DNRW.

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Chapter 4. Management Actions

Summary 1. A range of actions to reduce pollutant losses from point and diffuse sources was identified through consultations with stakeholders and scientific investigations.

2. These actions were assessed against both effectiveness in reducing in pollutant loads and acceptability within the Shire. Effectiveness was directly estimated for point source management actions, and obtained from CSIRO modelling for diffuse source actions. Acceptability was obtained from a survey of Shire residents and from consultations with industry groups.

3. The acceptability of management actions was also identified in consultation with the Queensland and Australian Governments. All levels of Australian government have a national and international duty of care for the Reef, and are ultimately responsible to the broader community for its protection.

4. The most cost-effective means of reducing nutrient loss to the Reef is to reduce the application of phosphorus and nitrogen containing fertilisers to agricultural lands, as well as modify the timing and means of its application. The next most important action is to stabilise and repair cane drains to enhance their capacity to retain nutrients and sediment. It is proposed to achieve during the life of this WQIP a significant reduction in diffuse sources, as a proportion of all anthropogenic sources:

• A 4% reduction in the TN load (25 year RCT 6%, pre-European load 12%) • A 12% reduction in total sediment load (25 year RCT 22.5%, pre-European load 45%) • A 14% reduction in TP load (25 year RCT 16%, pre-European load 32%)

This is to be achieved through the consistent and reliable improvement in cane farm management, which includes; • application of fertilisers according to soil and plant tissue tests; • applying fertiliser sub-surface; • using slow-release fertiliser; • improved fallow management, and planting of leguminous crops (subject to further investigations); and • repairing two thirds of the cane drains to reduce sediment and nutrient loss. • Point source upgrades, primarily improvements in phosphorus removal at the Mossman STP, will contribute an 8% reduction in TP loads within 7 years.

Loads of each of the three pollutants will be reduced by about half that needed to reach the Aspirational target of pre-European loads, within a 25 year period – if all management actions proposed for this WQIP are implemented.

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5. Management actions were categorized into Immediate (i.e. during the life of this WQIP), Support or Long-Term depending on their joint acceptability and effectiveness. Immediate actions included: • upgrading Mossman STP and commissioning Wonga Beach STP; • connecting villages to an STP; • implementing nutrient loss reduction practices in sugar cane production; and • converting shallow drains in sugar cane fields to grassed swales.

6. There are commitments for a limited number of the priority implementation, monitoring, and research activities. Funded priorities include: • upgrades to sewage treatment and connection of unsewered villages; • continuing sugar cane nutrient loss management trials for one year; and • a Monitoring Alliance between Local, State, Federal & Wet Tropic NRM Board ensures a 2005/06 wet season monitoring program.

7. Notable unfunded priority activities include: • sugar cane nutrient reduction activities; • sugar cane shallow drain improvements; • monitoring effectiveness of management actions; and • research into drain stabilisation techniques.

The draft Douglas Shire Sustainable Futures plan47 was developed through extensive community consultation process and adopted by Council in 2001 as its blueprint for future development. It includes action plans that were developed with regard to their achievability in the short to medium term, recognizing the constraints on their implementation in the Shire. These action plans include a number of activities that will contribute to improved water quality, including: • the future viability of the cane industry needs to be assessed and potential diversification plans investigated; • canegrowers will adopt best practice recommendations and reduce run-off of water, sediment, fertilisers and pesticides from farm operations, retaining habitat and protecting wetlands; • existing codes of practice in each land based primary industry need to be assessed and implemented; • appropriate incentives should be introduced for property management planning to achieve general implementation of best practice in each primary industry; • off site effects of discharge water from aquaculture and forestry will be minimised by water recycling and amelioration, and by minimising runoff from forestry by reducing herbicides and erosion on steep slopes; • extractive industries will undertake best practices including minimising sediment reaching adjacent streams, and rehabilitation of unused quarries; • the Mossman STP will be upgraded to tertiary treatment; • non-sewered areas will be connected to STPs;

47 Douglas Shire Council (2001). Sustainable Futures: Draft Strategy. Developed by Douglas Shire Sustainable Futures Community Working Group in Conjunction with Douglas Shire Council and Environmental Protection Agency.

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• marine effluent will be pumped to Pt Douglas STP; • effluent will continue to be reused for irrigation in Port Douglas and effluent reuse will be included in upgrades of the Mossman STP; • individual household sewage treatment systems will incorporate best practices; • perverse incentives on water efficiency will be removed so that composting toilets and re-use of grey water is encouraged; and • water re-use will be encouraged for domestic, commercial, industrial and community facilities.

4.1 Point Source Management Action Possible management actions for point sources were examined in Project 3 of this Water Quality Improvement Plan48.

4.1.1 Mossman Sewage Treatment Plant. There are 2 municipal sewage treatment plants in the Douglas Shire. Port Douglas STP is tertiary and treated effluent is reticulated for reuse. Mossman STP is secondary treated and is scheduled by Council for upgrade to tertiary. There is scope when upgrading to design reticulation for reuse. While meeting present licence conditions, Council recognises that upgrade is required to meet best practice. Plans are underway for the upgrade to occur within 6 years, i.e. during the life of this WQIP.

4.1.2 Aquaculture. The major aquaculture facility in the Shire, Seafarm Pty Ltd, located in Dickson Inlet, is committed to reducing its nutrient discharges to the ocean. Currently it produces a small fraction of its licensed effluent discharge, although the recently released QEPA Operational Policy, “Licensing Wastewater Releases from Existing Marine Prawn Farms in Queensland” may require improvements in the effluent quality from prawn farms such as Seafarm (Table 4.1). Smaller aquaculture operations may need to upgrade their effluent management operations in the longer run (over 25 years) with more advanced recycling and purifying techniques.

Emerging best practice for prawn farming may entail the introduction of recirculation technology, which would not only considerably reduce the amount of nutrients discharged from the farm but also reduce the risk of introduction of serious diseases to the farm in the intake water. Overseas experience has shown that the introduction of recirculation systems in prawn farms lead to increases in profits and productivity due to more efficient use of food and reduced disease problems. The lesser amount of wastewater released from a farm with recirculation technology can be more readily treated to significantly reduce the amount of nutrients released to waters49.

48 Project Three “Control of Point Source Discharges of Sediment and Nutrient In Douglas Shire”, Activity Three “Identification of Treatment Upgrade Activities” Milestone Report – July 2003 Environmental Protection Agency, Douglas Shire Council. 49 Project Three “Control of Point Source Discharges of Sediment and Nutrient In Douglas Shire”, Activity Three “Identification of Treatment Upgrade Activities” Milestone Report – July 2003 Environmental Protection Agency, Douglas Shire Council.

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Table 4.1: Industry Codes of Practice in Queensland. Sugar Cane “Sustainable Cane Growing in Queensland” - Code of Practice. Grazing No Queensland Code of Practice has been developed. Horticulture “Farmcare – Cultivating a Better Future” CoP of sustainable fruit & vegetable production in Queensland Farm No CoP has yet to be developed for Queensland. However the Queensland Forestry Department of Primaries has developed a draft “Guidelines for the Consideration of Plantation Forestry in the Preparation of Integrated Planning Act (1997)”. This paper is being developed for Local Government and others. Aquaculture This industry is administered under licence from the Queensland QEPA. They have developed an “Operational Policy for Marine Prawn Aquaculture”. This QEPA endorsed policy is for use in the evaluating and setting appropriate wastewater discharge standards for prawn farming Protected The Wet Tropic Authority has produced two recent documents “Water Infrastructure Areas Code of Practice” & “Field Guide for the Maintenance & Operation of Water Extraction Infrastructure in the Wet Tropics”. These have been approved by the WT Board as a Section 62 guideline, which means it is used as an assessment measure when assessing any permits & conditions for water infrastructure in the World Heritage Areas. They are also intended to be an educational tool for all operators of water infrastructure and are seen as an infield manual for best practice.

QEPA has recently released their BMP document to be adopted within National Parks. The document highlights direction that QEPA will adopt when undertaking works programs in track establishment and maintenance and effluent management. In the management of feral pests and weed the document relies on present strategies adopted by State Agencies.

4.1.3 Tourist Boats. Commencing 2010, amendments to the Transport Act will require that all tourist boats with a licensed capacity of greater than 6 people will be required to collect wastes and pump-out to shore facilities at Port Douglas. Douglas Shire Council50 has upgraded the replaced Port Douglas STP to accept saltwater effluent and has run the effluent lines past the marinas for their connection to boat effluent pump-out facilities in these areas.

Acceptance of these measures is mixed, with the largest tourist boat operator at Port Douglas, Quicksilver, having already converted two vessels while other operators are waiting until closer to the compliance date.

River boat tours operates predominantly on the Daintree River, with one on the Mossman River. Bank erosion from boat wash is evident and results from exceeding the speed limit and/or design of the vessels. A higher frequency of compliance checks within the marine reserve, plus educational packages to the operators would minimise the impact. The QEPA do not have jurisdiction above the marine reserve where many operators run tours.

50 The upgrade was funded by the Local Government Bodies Infrastructure Subsidy.

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4.1.4 Quarrying. Council has moved to control extraction permits for volumes under 5,000 m3. Some permits have been revoked because of erosion issues or allowing the permits to elapse, while other land owners have been required to submit erosion management plans before quarrying permits are reissued. After recent auditing of these quarries only eleven permits remain active. Sediment loss is expected to be substantially reduced at a local level as a result of these actions.

Extracting over 5,000 m3 is an Environmental Relevant Activity, requiring QEPA’s approval. Three quarries exceed 5,000 m3 and QEPA will continue compliance checks regularly.

4.1.5 Stormwater. All new suburbs have sediment traps installed to intercept runoff and remove sediments and attached pollutants. At this stage Council has no program to retrofit older areas, although this would reduce local pollution during storm events.

4.1.6 Development Sites. Council is instituting stricter conditions for approving developments. Erosion control plans need to be submitted upon approval of the development proposal. As part of this WQIP, Council has also instituted an awareness compliance program via site visits and the publication of water sensitive design guidelines. These are expected to lead to a steady reduction in soil losses from these sites, and will be a continued program.

4.1.7 Septic – Residential. Council has approved plans to connect Cooya Beach, Newell Beach and Wonga to the Mossman STP to remove this source of pollution, estimated at 20.9 tonnes TN/yr and 9.7 tonnes TP/yr. This upgrade will be completed in 6-7 years. Craiglie connection to Port Douglas STP is to be undertaken in the 2005/2006 financial year.

Septic systems in rural areas need to be addressed by a higher level of maintenance, i.e., a regular pump-out system of all septics registered on a central database. Under the Standard Sewage Law, Douglas Shire Council has powers to deal with poorly maintained, overloaded or defective on-site sewage facilities. Replacement of all septic systems to more sustainable systems requires high infrastructure costs to the community affected. To this end Council will institute a risk-based inspection programme for septic tanks and their maintenance by property owners.

4.2 Diffuse Source Management Action Actions for controlling diffuse pollution sources were developed through examination of industry codes of practice (Table 4.1) and consultations with industry representatives in the Shire through the preparatory projects funded under this Plan51.

51 Various activities within Project 2 of this Water Quality Improvement Plan. DM Smith, PC Roebeling, AJ Webster, M Kragt, I Bohnet, A Zull (2004). Assessment of the Socio-Economic Impacts of Management Options for Improving Water Quality in Douglas Shire. CSIRO, Townsville.

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4.2.1 Reducing nutrient losses – Sugar cane. Sugar cane has been identified as a major anthropogenic source of dissolved N as a result of losses from cane fields. Flume trials conducted as part of the CCI, although only conducted for a short period, indicated that 11.5 kg/ha/yr of TN was lost through surface runoff and a further 16 kg/ha was lost through subsurface drainage over a 5-week period during the wet season (from 9 drainage events) when the fertilizer rates were 186 kg N/ha/yr. This trial measured losses from nitrogen applied as urea to the surface of a trash blanketed ratoon crop 58 days after harvest.

These losses could be reduced through a range of improved management practices52 without detrimentally affecting crop productivity, including reducing the nitrogen fertiliser application, applying the fertiliser sub surface, splitting applications or using a form of nitrogen fertiliser that is less mobile in the environment. Through consistent, reliable and shire-wide use of these actions it is possible in 7 years to reduce losses to the environment by 3%.

While the flume trials have provided preliminary data on nitrogen losses under two management practices, there is a need for further trials to establish the best combination of management practices to minimise nitrogen losses through surface and sub-surface pathways.

4.2.2 Fallow – Sugar cane Sugar cane farmers generally plough out a sugarcane crop after approximately 6 years of growth. In the Douglas Shire approximately half the ploughed-out areas are re-planted in the same year, without incorporating a period of fallow. The other half being planted into a fallow (which usually lasts approximately six months), of which approximately 30-40 percent is planted to legumes to benefit soil microorganisms and to fix nitrogen into the soil from the atmosphere. The balance of fallow ground is kept bare. The period of fallow is over the wet season, when soil losses can be high particularly from bare ground. Sediment losses can be reduced by eliminating tillage and maintaining cover during this fallow period.

According to CSIRO modelling53 financial returns can be potentially increased during this fallow period by planting leguminous crops leading to increased returns from subsequent crops (due to greater growth) and a reduced need for nitrogen fertiliser in the initial crop. While the industry is in agreement with the wider use of no-till fallow, questions remain over the benefit of leguminous crops during this period. Further research would need to be conducted to establish the practicality of a combined no-till and legume fallow period.

Given these responses, a 60% usage of no-till fallow is achievable within 7 years and a 100% usage is achievable within 25 years. Further research will be needed into use of legumes before it can be introduced.

4.2.3 Drain management – Sugar cane Preliminary estimates by CSIRO showed that drains – both shallow and deeper drains – in sugar cane areas were likely to be significant sources of sediment and attached nutrients during wet

52 “Sustainable Cane Growing in Queensland” - Code of Practice. 53 DM Smith, PC Roebeling, AJ Webster, M Kragt, I Bohnet, A Zull (2004). Assessment of the Socio- Economic Impacts of Management Options for Improving Water Quality in Douglas Shire. CSIRO, Townsville.

78 Draft Water Quality Improvement Plan periods. This result is consistent with local observations. To reduce sediment and nutrient losses, shallow drains can be regraded into broad, grassed spoon shaped drains that can provide additional headland areas for farmers while still allowing rainfall to run off. This would provide a private benefit to the farmer as well as a public benefit from reduced sediment loss.

The deeper drains would need to be stabilised, graded with sides no greater than 45 degrees and revegetated to reduce their loss of sediment. If necessary some drain banks may need to be armoured. The deeper drains on private land are maintained by landowners to prevent erosion of headlands. However, this level of maintenance is not always sufficient to control sediment loss from eroding banks. As there is no duty of care on existing drains placed on farmers, unless they are declared drains and embankment areas, appropriate market-based incentives need developing. Consequently, there is a public good aspect to undertake deep drainage stabilisation. Often widening drains results in a loss of productive area to the grower, providing a disincentive to uptake. The private land drains join the Council maintained stormwater system, which is used to remove runoff quickly and prevent flooding. Maintenance of these deep drains is entirely a public responsibility.

In order to achieve WQIP load reductions it is considered desirable for approximately 65% of the drains to be rehabilitated within 7 years (predominantly shallow drains) and a further 30% could be stabilised within 25 years to reduce this source of sediment.

Shire drains also require attention with many having slumping banks or deepening of channels. Junctions of cane and shire drains are generally perpendicular causing turbulence during high flows. Similar treatments for cane drains need to be applied to shire drains.

Remediation of drains must be put into the context that deep drains that are fed by shallow drains are generally straight lines, moving down slope. Measures as described above are required as rock-lining or concreting all deep drains would be cost-prohibitive. Investigation to determine the modified drainage pattern is required for potential end-of-drainage sinks capable of slowing waters and trapping loads. A risk-based approach will be taken to drain remediation and investigation of more expensive options. Monitoring programmes will be designed to assess the effectiveness of these interventions

4.2.4 Ground cover – Grazing Drainage lines (first and second order streams) on sloping country in mid-Daintree catchment have been identified as at risk of hillslope erosion at the end of the dry season when burning occurs to control weeds. By maintaining land cover as long as possible or by modifying the fire regime to exclude drainage lines on the slope this risk can be minimised. Alternative methods of weed control, such as use of herbicides, may need to be developed. There is no Code of Practice yet available for the grazing industry in Queensland. The Daintree graziers are developing their own BMPs suited to their environmental conditions however, the extent to which these BMPs will address the WQIP objectives remains unclear.

4.2.5 Riparian management – Cassowary Creek (Mossman Catchment) Cassowary Creek has been identified in earlier studies as having significantly worse water quality than other streams in the Shire. The causes have not been identified although poor management of riparian areas either acts as a source of sediment and attached nutrients or fails to trap pollutants originating from other sources. At least 80% of the riparian areas can be

79 Draft Water Quality Improvement Plan rehabilitated within 7 years and 95% of the riparian areas can be revegetated within 25 years. This will not only minimise stream bank collapse but will intercept sediments and pollutants before they reach streams and provide improved habitat for aquatic life. A similar survey to that undertaken at Upper Whyanbeel and Stewart Creek is required in Cassowary Creek to identify the hot spot sites in this subcatchment.

4.2.6 Riparian management – Rest of Shire Studies54 have highlighted the poor condition of many of the riparian areas of streams throughout the Shire. Stabilizing riverbanks and developing a buffer strip to trap pollutants would improve the water quality in downstream areas. Based on field surveys conducted as part of this Plan preparation, 50% and 95% of riparian areas (excluding Cassowary Creek) can be rehabilitated within 7 and 25 years respectively. Twenty three voluntary management agreements have already been negotiated with land holders in the DSC as part of the “no regrets“ strategy of the WQIP to improve stream-bank and riparian areas with cost sharing between the landholders and Government. A further five sites are being negotiated to fully commit CCI funding.

4.2.7 Fertilizer and soil management – Horticulture Although there are only small areas of horticulture in the Shire, local stream water quality could be improved through reductions in nutrient losses through rate and type of fertiliser use. Soil loss remains a high risk where ground cover is not maintained during the wet season. While improving these management practices is not expected to have a major effect on total pollutants loads reaching the Shire’s estuaries, it could improve local water quality immediately downstream of these horticultural enterprises. Implementing best management practices through the “Farmcare – Cultivating a Better Future” CoP will require some assistance with extension activities and also with research (Table 4.1).

4.2.8 Sediment management – Roads Studies in southern Australia have illustrated the sediment loads reaching streams and rivers from unsealed roads and verges and from sealed road verges during storms. These loads can be reduced through management interventions such as sealing high impact roads, introducing infrastructure to trap sediments (this requires regular maintenance), and maintenance of ground cover on verges where possible. DSC was previously active in establishing grass verges that were maintained by slashing. This practice also reduced weed invasion. This practice needs to be continued.

54 GHD (1994). Strategic management Plan for the major rivers and streams of the Douglas Shire: Phase 1 – Scoping Study. Russell, D. J., McDougall, A. J. and Kistle, S. E. (1998): Fish Resources and Stream Habitat of the Daintree, Saltwater, Mossman and Mowbray Catchments. Information Series QI98062, Department of Primary Industries (Fisheries), Northern Fisheries Centre, Cairns:72pp. + maps. Werren, G.L. (2003): Douglas Shire Water Quality Strategy. Project 4.3: Phase 1 Report - assessment of nature and condition of riparian systems and related wetlands of Douglas Shire with a focus on prioritising areas for restorative work to reduce sediment/contaminant runoff. Werren, G.L. (2004): Draft Douglas Shire Water Quality Improvement Project. Project 4.3: Phase 2 Report – reappraisal and refinement of priorities for restorative works to reduce sediment and contaminant runoff.

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4.2.9 Reduced soil and nutrient losses - Forestry Since 2002, the QEPA has implemented a Code of Practice (CoP) for Native Forest Timber Production across all State forests in Queensland (Table 4.1). This CoP includes the design and management of roads and snig tracks and the use of buffer strips on streams and sensitive areas to minimise sediment losses, as well as fertiliser and pesticide usage that minimises losses. However, there is no CoP in place for forestry on private land although logging is prohibited in private forests within the WHA. Practices similar to those in use in the State forests should be expected to be introduced for all forest lands within 7 years. Forestry management actions will not be considered further in this plan while the CoP is being developed. However, once the CoP is available, they will be introduced as the plan is revised.

4.2.10 Feral Pig Management The control of feral pigs, especially in areas that are inaccessible such as National Parks, is a challenging management issue. Anecdotal evidence suggests that pig damage in National Parks is high. However, there has been no quantitative work undertaken in this shire to assess their contribution. As a task within the WQIP process the QEPA highlighted the BMPs for the World Heritage Areas, National Parks and State Forests. The QPWS adopts the DNRW standards, codes, policies and strategies for pest management. Feral pig management actions will not be considered further in this plan, but there is clearly a need by QEPA to address this issue.

4.3 Criteria for Assessment The reductions in pollutant loads from point and diffuse source management actions will have both local and Shire-wide benefits. Local benefits with individual river reaches include reduced risk of eutrophication and weed growth, fewer bars and in-river deposition areas, maintenance of aquatic food webs, and improved water clarity. These local benefits in a particular river reach may not influence the Shire-wide water quality because the total mass of sediments and nutrients from that river reach is small compared to those coming from other sources. Both local and Shire-wide improvements in pollutants are important and will be used in assessing management actions. However, the priority for implementing this WQIP is to reduce pollutant loads to the GBR.

Improvements will be assessed on both effectiveness and acceptability criteria. The former measure the extent to which a particular management action will contribute towards total pollutant load reduction to the GBR. The latter measures the relative likelihood of a management action being adopted and implemented. Management actions that are both effective and acceptable should be implemented as soon as possible; the uptake of effective actions with low acceptability will need to be increased through increased incentive and education programs. The adaptive management approach outlined in section 4.9.1 includes strategies to evaluate both effectiveness and acceptability, and if uptake of key ‘acceptable’ BMPs is low, further incentives to encourage and/or require intervention will be need to be investigated and implemented in order to protect the Reef and the industries that rely on it.

Point source management actions that will impact on reducing pollutant loads are easier to implement with appropriate mechanisms of education and incentives compared to diffuse sources due to availability of control actions, e.g. Environmental Protection (Water) Policy, 1997.

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4.4 Cost Benefit Analysis The CSIRO has conducted both a cost benefit study and a survey of acceptability for the sugar cane and grazing management actions listed above. The survey was conducted with all households with postal addresses in the Shire55. Other management actions such as riparian and wetland protection were not analysed due to the lack of suitable data.

The survey data was used with models of sugarcane and grazing production to estimate the changes in net present value of production from sugar cane, grazing and mixed cane-grazing farms under the different management actions. The results were also aggregated across the Shire to give total private benefits from the management actions. These analyses include only private benefits – both improved income and increased leisure time – and do not include any public benefits such as enjoyment of clearer water or reduced water filtration costs. Finally, some estimates were made of the benefits to the marine industries of reduced sediment loads on reef cover and fish biomass (nutrients were not modelled because of uncertainties about the links between nutrients and offshore benefits).

The results are summarized in Table 4.2. The baseline conditions are the current aggregate gross incomes (defined as the gross margin from agricultural production plus on- and off-farm labour income, excluding taxes, fixed asset depreciation and maintenance costs, and capital costs) based on 2002 levels of production and prices.

Table 4.2: Producer surplus* (million A$ per annum) to both terrestrial and marine industries from selected management actions, based on sediment management. All crop Tillage Fallow N- mgmt Stocking Drain Catchment Baseline Systems Practices application actions Rate Management Mowbray 1.65 1.71 1.98 1.95 2.23 1.65 1.63 Mossman 2.49 2.59 2.99 2.95 3.37 2.49 2.47 Daintree 3.28 3.33 3.54 3.51 3.72 3.03 3.27 Saltwater 2.56 2.65 3.07 3.01 3.43 2.55 2.53 Total Terrestrial 9.98 10.28 11.58 11.43 12.75 9.72 9.90 Marine 18.25 18.27 18.25 18.21 18.30 18.23 20.37 Total 28.23 28.55 29.83 29.64 31.05 27.95 30.27 *Terrestrial producer surplus = aggregate regional value of agricultural production and employment net of corresponding production and labour costs *Marine producer surplus = aggregate regional value of marine-based production net of corresponding production and labour costs

Minimum tillage, legume fallows and optimal management of N fertilisers were estimated to lead to an increase in terrestrial producer surplus. When applied together (all crop management actions) gross income was estimated to increase by over 35 % for both specialised sugarcane farmers and mixed (sugarcane and beef) farmers. However, when all farmer types are included, the increase in gross income is reduced to 10%.

55 Smith, D.M., P.C. Roebeling, A..J Webster, M Kragt, I. Bohnet, A. Zull (2004). Assessment of the Socio- Economic Impacts of Management Options for Improving Water Quality in Douglas Shire. Report to Douglas Shire Council. CSIRO Sustainable Ecosystems, Townsville.

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Riparian management was not examined for its aggregate benefit because of the uncertainty in the quantitative economic benefits of prescriptive measures and the benefits gained. A component to the Tully WQIP is examining this issue.

Suggested changes to the management of grazing operations – specifically exclusion of stock from riverbanks and reduced stocking rates56 – was estimated to cause income losses for graziers. Reducing stocking rates to recommended levels of less than 2 head/ha caused income for specialised graziers to decline by more than 10 %.

Total agricultural producer surplus for the Shire was estimated to increase by almost 30% because of adoption of minimum tillage, legume fallows and optimal N fertiliser management in sugarcane farming. Improved management of cane drains and reduced stocking rates caused producer surplus to decline by about 3%.

To align this information within the context of triple bottom line analysis many of the actions provides a benefit at both farm-scale and shire-scale levels. The negative economic impact on industry by improved management of cane drains does provide a positive outcome for the marine industry. As Table 4.2 indicates for improved drainage management the baseline terrestrial producer surplus of $9.98M is reduced to $9.90M, while the marine industry’s surplus increases from a baseline of $18.25M to $20.37M. This is clearly an indication that the marine-based industries may have a role in assisting in improved drain management, particularly where those management activities are beyond established duty of care obligations on land managers.

Analysis of the benefits of pollution control for reef tourism and fisheries showed that effects of reduced sediment runoff on these sectors were small, except for drains management, where the estimated growth of the producer surplus for the marine-based industries exceeded 10 %. These estimates excluded the effects of reduced nutrient pollution on marine systems and are therefore conservative. When the costs and benefits for terrestrial industries and marine industries were combined, all management actions caused positive net welfare effects for the Shire, except grazing BMPs, which caused a small decline in total producer surplus.

4.5 Consultation Discussions have been held with relevant industries about these management actions; • two rounds of ‘shed’ meetings have been held with the sugar cane growers to discuss and assess potential BMPs. Shed meetings will continue after the 2005 harvest season; • a seminar was conducted with the restaurant/accommodation operators (March 2004) with assistance from the Port Douglas/Daintree Tourist Association to obtain their views on improved management practices and to assess their current level of adoption; • there have been informal consultations with the grazing industry and with a workshop/field day forum on pasture management/stock access held on September 2004 with a second workshop undertaken in April, 2005 that highlighted management action in grazing; • independently of the production of this Plan, DSC has held a public meeting with marine operators and live on-board community members to discuss provision of pump-out facilities for tourist and private boats;

56 Stocking rates based on QDPI recommendations for wet tropics.

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• a series of consultations with stakeholders were held to develop Environmental Values (Chapter 2). The last meeting also addressed the cost/benefits of the determined key actions; and • CSIRO has conducted a postal survey of resident attitudes towards environmental values and management actions.

The level of acceptability of the sugar cane and grazing management actions57 from the CSIRO analysis is shown in Table 4.3. Other management actions were not included. Actions were, on average, rated by respondents with high or medium high expectation of effectiveness and support for adoption. About 20 % of respondents were sceptical of many actions. Scepticism was especially high among farmers for the effectiveness of stock exclusion, riparian revegetation and wetland restoration although these actions received strong support amongst the community generally.

Table 4.3: Summary of relative social and economic acceptability in Douglas Shire of actions for managing improvements in water quality, where high indicates a positive effect and low a negative effect; neutral indicates effects are mixed and small. Management action Property level acceptability Shire level acceptability Economic Social Economic Social Minimum tillage high high high High Fallow practice high high high High Fertilizer management high high high in growing sector high in growing sector low in regional industry low in regional industry Combined cropping high high high in growing sector high in growing sector system BMPs1 low in regional industry low in regional industry Drains management low (neutral) low for sugar industry low for sugar industry Stocking rate low low low for grazing industry low for grazing industry Stock exclusion low low low for grazing industry low for grazing industry Riparian revegetation low low, unless low for agriculture low for agriculture individual preference Infrastructure - - high if cost effective high if cost effective Overall net effects on - - high High Shire

4.6 Land Use Change Changes in land use can increase or decrease sediment and nutrient loads to rivers, depending on the pollutant export characteristics of the prior and post land uses. The Shire’s current land use pattern (Chapter 1) is undergoing a gradual shift towards more tourist based activities and an increase in the market demand for rural residential/lifestyle blocks of, typically, 1-2 hectares. The urban areas are growing rapidly with the dominant driver behind this growth being residential allotments in Port Douglas, Mossman and Cooya Beach townships. In the 2004-2005 financial year approximately 1000 new residential allotments were approved in these areas ranging from 600m² up to 1500m² with average lot sizes around 800m². These approvals constitute a supply of approximately 7-8 years demand for residential allotments and will be

57 Smith, D.M., P.C. Roebeling, A..J Webster, M Kragt, I. Bohnet, A. Zull (2004). Assessment of the Socio- Economic Impacts of Management Options for Improving Water Quality in Douglas Shire. Report to Douglas Shire Council. CSIRO Sustainable Ecosystems, Townsville.

84 Draft Water Quality Improvement Plan staged by their respective developers to correlate with this trend. The maximum number of residential allotments in Port Douglas as a result of full development is estimated to be approximately 1200-1400, for Mossman approximately 1200 and Cooya approximately 550. These limits are set by available land under the current DCP and Council’s draft Planning Scheme.

These changes are driven by market forces and the Council does not have a leading role in instituting these changes. The Council’s role is to introduce plans and regulations that guide the development in socially and environmentally beneficial ways. Consequently, in this plan, land use changes can only be presented as possible developments rather than as initiatives by the Council and other authorities. However, with DSC being key stakeholder manager there is a need for Council to have both the capability and capacity to manage growth, eg to a full adoption of water sensitive urban design, or appropriate level of resources for compliance inspection on development sites. While Council have completed their Planning Scheme, which is awaiting approval by the Minister, there is still a need to address the pressures driven by market forces to allocate agricultural lands to residential and “hobby farms”. Recommendations from the proposed Rural Landscape Review do require incorporation into the Council decision making dealing with change of landuse.

There is a possibility of a significant decline in the price of sugar because of international factors, leading to the withdrawal of some farmers from the industry, the closure of the mill and the subsequent loss of viability by the remaining sugar cane farmers. This would lead to the conversion of the current sugar cane land use to other land uses such as horticulture, farm forestry, rural residential blocks, cocoa production, stock feed, etc. Given industry uncertainty eco-efficiency measures to reduce pollutant loads continue to be a priority management action under this WQIP, and for which whole of shire adoption is proposed during the period of this WQIP.

However, for the purposes of predicting possible changes in pollutant loads, the most likely land use change is a small decline in the area under sugar cane as some of the more marginal land goes out of sugar cane production. This change is driven by declining returns under more competitive market conditions rather than through any attempt to improve water quality. However, the industry remains viable with sufficient productivity improvements elsewhere for the mill to remain in production although it may diversify the range of products, eg GI sugar and chocolate. This scenario was modelled by the CSIRO for its pollutant implications as follows: • 20% of the sugar grown on slopes of between 3-10% converted to farm forestry, • 20% was converted to rural residential allotments, and • 20% was converted to grazing. • The remaining 40% stayed under sugar production.

4.7 Changes in Pollutant Loads The effectiveness of a management action in reducing pollutant loads is an important measure, along with its acceptability, in assessing its implementation requirements. The CSIRO EMSS and SedNet models (Appendix B) were used to predict the changes in total suspended sediment, total nitrogen and total phosphorus loads from some of the management actions. The models were not capable of assessing all management actions because of structural limitations and the scale at which they predicted. The models were run once for two time periods – 7 years and 25 years from current (2005).

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All point source management actions (Section 4.1) and the possible changes to sugar cane land uses (Section 4.6) were included in the model runs (Appendix B). The likely effects of the remaining management actions were estimated manually and included with the modelled results in the following tables.

A number of modelling results were modified using expert opinion because of obvious inconsistencies or because more spatially reliable information was available. The modelled reductions in sediment loads from reducing erosion from cane drains were too high, approaching pre-European values. These results were reduced by 50%. The modelled stabilization of eroding stream banks throughout the Shire appeared to have too low an effect, especially in subcatchments that were known to have extensive bank erosion. Field surveys were carried out in the Stewart Creek/Douglas Creek and upper developed Daintree regions and direct estimates were made of annual bank erosion rates in these two subcatchments.

The 7-year and 25-year scenarios results are described in Table 4.4(a-d). The table shows the reductions in pollutant loads as a percentage of the total Shire pollutant loads for each management action that was modelled, by river reach. The full modelling results, including the effects on local river reaches, are shown in Appendix B, section 5

The errors in the estimated reductions in most diffuse source loads from the modelling are not known, but are likely to be large given the uncertainties of 200-500% in the calculation of absolute loads. However, the reductions in pollutant loads from manual calculations are estimated to be more accurate with errors of about 100%, except for the reduced TN from improvements in management of sugar cane and the reduced pollutant loads from point source upgrades. The load reductions from these two interventions are reliable since the first will result from a loss reduction approach and the latter from engineering improvements. Overall, the predicted changes in pollutant loads are small percentages of the total Shire pollutant loads and much less than the modelling errors. While the absolute value of these reductions cannot be accepted with any reliability, they can be used qualitatively to identify the more effective actions at local level and at whole-Shire level.

The effect of any conversion of the more marginal, higher-sloped sugar cane farms to rural residential, farm forestry or grazing on pollutant loads was also modelled. These land use changes, if they were to happen, are predicted to not have an effect on the Shire wide pollutant loads although they will lead to some moderate local TSS reduction in the Mossman – National Park” and, possibly, some minor TSS reduction in the “Saltwater Creek – National Park” river reaches.

4.7.1 Pollutant Load Reductions Repairing and stabilising cane drains (both shallow drains and deep drains) is the most effective management action for reducing sediment loads, leading to a 12% reduction in the total sediment load delivered by Shire Rivers in 7 years if two thirds of the drains are repaired, and 18% reduction if 95% are repaired in 25 years. The majority of this sediment reduction occurs in the “Coastal Strip” and “Mossman Developed” river reaches.

None of the individual management actions has a major effect on TN loads reaching the Barrier Reef lagoon. The most effective nitrogen loss reduction strategy is to reduce losses of nitrogen

86 Draft Water Quality Improvement Plan from sugar cane fields. This will have a small, beneficial effect on TN loads. However, as discussed below, the increase in TN loads since pre-European times is estimated to have been relatively smaller for TN than for the other pollutants and so improvements are significant and appropriate to target.

Because phosphorus is primarily transported attached to soil particles, repairing drains in sugar cane areas will also reduce TP loads. Thus, TP loads could be reduced by up to 4% if 90% of drains were stabilized within 25 years. Point source upgrades, primarily improvements in phosphorus removal at the Mossman STP, will lead to a further 8% saving in TP loads within 7 years. It is assumed here that there will be no further improvements to point sources after 7 years.

Figure 4.1 shows the approach towards achieving the Resource Condition Targets for the three pollutants of concern. A 22.5% reduction in current TSS loads is needed to reach the RCT (21% will be achieved after 25 years with the management actions); a 6% reduction in TN is needed (6% will be achieved after 25 years); and a 16% reduction in TP loads will be needed compared to the 17% reduction after 25 years under the Plan. That is, if all management actions discussed here are implemented, the RCTs will be achieved, or nearly so (and in the case of TSS exceeded). However, the uncertainties are so great in the estimates of the pre-1850 loads, and in precise knowledge of the level of impacts on the Reef of pollutant loads, that RCTs as well as the Aspirational targets will need to be recalculated as better information becomes available.

There are a number of management actions that will be effective in reducing pollutant loads locally within the Shire. Repairing sugar cane drains is highly effective at reducing sediment loads in the “Coastal Strip”, “Daintree South Arm – Estuary”, “Mossman – Developed”, “Mossman – Estuarine”, “Saltwater- Developed” and “Saltwater- Estuary” reaches. Maintaining good ground cover on steeper grazing land (Management Action 4) will significantly reduce local sediment loads in the “Mowbray- Developed” river reach. Even though the predicted load reductions have large errors, there will clearly be major local benefits from controlling these sources of sediment and attached TP.

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Figure 4.1. The predicted reductions in TSS, TN and TP as a result of the proposed management actions.

TSS

160,000 140,000 120,000 Current 100,000 7-year 80,000 60,000 25-year TSS (t/yr) TSS 40,000 Pre-1850 20,000 0 Current 7-year 25-year Pre- 1850 Time

TN

2,300 2,200 Current 2,100 7-year 2,000 25-year TN (t/yr) TN 1,900 Pre-1850 1,800 Current 7-year 25-year Pre- 1850 Time

TP

200

150 Current 7-year 100 25-year TP (t/yr) 50 Pre-1850

0 Current 7-year 25-year Pre- 1850 Time

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While reducing TN losses from sugar cane fields has little regional effect, it does have very significant local effect in the river reaches where sugar is grown, such as the “Coastal Strip”, “Daintree South Arm – Estuary”, “Mossman – Estuarine” and “Saltwater- Estuary” reaches. These local improvements in TN loads can have significantly beneficial effects within those particular river reaches, even though they are overwhelmed by the loads of TN continuing to come from the parts of the Shire where sugar cane is not grown.

The management actions that are locally effective for sediment load reduction are also effective for TP reduction. In addition, upgrading point source treatment (including connecting un- sewered villages to the reticulated sewerage system) reduces exports of TP to the near shore area (“Coastal Strip”) and the “Mossman – estuarine” river reach.

4.8 Categorizing Management Actions In this section, we bring together considerations of both the acceptability and the local and Shire- wide effectiveness of the management actions in order to categorize the management actions (Table 4.5). Land use changes are not included here since they are driven by forces outside this plan (refer to 4.6). For this purpose, effectiveness is categorized as High, Medium or Low because of the large uncertainties associated with most of the calculations in Tables 4.4.

Management Actions that: • are either already approved or have a high acceptability rating, and • have a high or moderate local or Shire-wide effectiveness for at least one of the pollutants, are accorded an “Immediate” category. These Management Actions can be implemented in the short term because they have a high likelihood of being implemented and will also make a significant impact on pollutant loads either locally or Shire-wide.

Those that have: • a moderate acceptability, and • a high or moderate local or Shire-wide effectiveness for at least one of the pollutants or • low acceptability, and • a high local or Shire-wide effectiveness for at least one of the pollutants are accorded a “Support” category. They have the potential to making an impact on pollutant loads if their acceptability can be improved through appropriate management actions such as education, subsidies or new technologies.

Management actions that have low acceptability and low or moderate effectiveness are identified as “Long-term” actions because they will take considerable effort to implement and will not have much effect on pollutant loads, even locally.

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Table 4.4(a): Pollutant load and management action targets for the Daintree River catchment. Management Action Load reductions WQIP (7 Yr) 25 Yr TSS TN TP TSS TN TP SUGAR CANE N/A 0 N/A N/A 1 N/A 1) Improved sugar cane management by reducing N losses by 35% (7yr), 50% (25yr) (Section 4.2.1, 4.2.2) 2) Repair/modify drains by 65% (7yr), 95% (25yr) (Section 4.2.3) 1 0 0 2 0 0 3) Introduce 60% legume planting during sugar cane fallow period 0 0 0 0 0 0 (7yr), 100% (25yr) GRAZING 0 0 2 0 0 2 4) Maintain yearly average cover of 95% on slopes >8% slope 5) 80% improvement to riparian vegetation in Daintree grazing area 0 0 0 0 0 0 6) Manage burning practices to minimise runoff2 Z Z Z Z Z Z 7) 50% improvement to riparian vegetation in other catchments (7yr), 0 0 0 0 0 0 100% (25yr) HORTICULTURE Z Z Z Z Z Z 8) Adopt Farmcare Code of Practice2 POINT SOURCES N/A 0 0 N/A 0 0 9) 75% reduction of pollutant loads for sewage and stormwater ROAD MANAGEMENT Z Z Z Z Z Z 10) Sealing high impact roads; trapping sediment runoff; maintaining ground cover on verges2 Total load reduction 1 0 2 2 1 2

Table 4.4(b): Pollutant load and management action targets for the Mossman River catchment. Management Action Load reductions WQIP (7 Yr) 25 Yr TSS TN TP TSS TN TP SUGAR CANE N/A 1 N/A N/A 1 N/A 1) Improved sugar cane management by reducing N losses by 35% (7yr), 50% (25yr) 2) Repair/modify drains by 65% (7yr), 95% (25yr) (Section 4.2.3) 3 0 1 3 0 1 3) Introduce 60% legume planting during sugar cane fallow period 0 0 0 0 0 0 (7yr), 100% (25yr) GRAZING 0 0 0 0 0 0 4) Maintain yearly average cover of 95% on slopes >8% slope 5) Manage burning practices to minimise runoff N/A N/A N/A N/A N/A N/A RIPARIAN 0 0 0 2 0 3 6) 80% improvement to riparian vegetation in Cassowary sub- catchment (7yr), 95% (25yr) 7) 50% improvement to riparian vegetation in other catchments (7yr), 0 0 0 0 0 0 100% (25yr) HORTICULTURE 0 0 0 Z Z Z 8) Adopt Farmcare Code of Practice POINT SOURCES N/A 0 1 N/A 0 1 9) 75% reduction of pollutant loads for sewage and stormwater ROAD MANAGEMENT Z Z Z Z Z Z 10) Sealing high impact roads; trapping sediment runoff; maintaining ground cover on verges Total load reduction 3 1 2 5 1 5

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Table 4.4(c): Pollutant load and management action targets for the Mowbray River catchment Management Action Load reductions WQIP (7 Yr) 25 Yr TSS TN TP TSS TN TP SUGAR CANE N/A 0 N/A N/A 0 N/A 1) Improved sugar cane management by reducing N losses by 35% (7yr), 50% (25yr) 2) Repair/modify drains by 65% (7yr), 95% (25yr) (Section 4.2.3) 0 0 0 1 0 0 3) Introduce 60% legume planting during sugar cane fallow period 0 0 0 0 0 0 (7yr), 100% (25yr) GRAZING 0 0 0 0 0 0 4) Maintain yearly average cover of 95% on slopes >8% slope 5) Manage burning practices to minimise runoff N/A N/A N/A N/A N/A N/A RIPARIAN 0 0 0 0 0 0 6) 50% improvement to riparian vegetation in other catchments (7yr), 100% (25yr) HORTICULTURE N/A N/A N/A N/A N/A N/A 7) Adopt Farmcare Code of Practice POINT SOURCES N/A N/A N/A N/A N/A N/A 8) 75% reduction of pollutant loads for sewage and stormwater ROAD MANAGEMENT Z Z Z Z Z Z 9) Sealing high impact roads; trapping sediment runoff; maintaining ground cover on verges Total load reduction 0 0 0 1 0 0

Table 4.4(d): Pollutant load and management action targets for the Saltwater Creek catchment Management Action Load reductions WQIP (7 Yr) 25 Yr TSS TN TP TSS TN TP SUGAR CANE N/A 1 N/A N/A 2 N/A 1) Improved sugar cane management by reducing N losses by 35% (7yr), 50% (25yr) 2) Repair/modify drains by 65% (7yr), 95% (25yr) (Section 4.2.3) 2 0 2 4 0 2 3) Introduce 60% legume planting during sugar cane fallow period 0 0 0 0 0 0 (7yr), 100% (25yr) GRAZING 0 0 0 0 0 0 4) Maintain yearly average cover of 95% on slopes >8% slope 5) Manage burning practices to minimise runoff N/A N/A N/A N/A N/A N/A RIPARIAN 0 0 0 0 0 0 6) 50% improvement to riparian vegetation in other catchments (7yr), 100% (25yr) HORTICULTURE Z Z Z Z Z Z 7) Adopt Farmcare Code of Practice POINT SOURCES N/A 0 0 N/A 0 0 8) 75% reduction of pollutant loads for sewage and stormwater ROAD MANAGEMENT Z Z Z Z Z Z 9) Sealing high impact roads; trapping sediment runoff; maintaining ground cover on verges Total load reduction 2 1 2 4 2 2

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Table 4.4(e): Pollutant load and management action targets for the Coastal Strip1 Management Action Load reductions WQIP (7 Yr) 25 Yr TSS TN TP TSS TN TP SUGAR CANE N/A 1 N/A N/A 1 N/A 1) Improved sugar cane management by reducing N losses by 35% (7yr), 50% (25yr) 2) Repair/modify drains by 65% (7yr), 95% (25yr) (Section 4.2.3) 6 0 1 8 0 1 3) Introduce 60% legume planting during sugar cane fallow period 0 0 0 0 0 0 (7yr), 100% (25yr) 4) Manage burning practices to minimise runoff N/A N/A N/A N/A N/A N/A RIPARIAN 0 0 0 0 0 0 5) 50% improvement to riparian vegetation in other catchments (7yr), 100% (25yr) HORTICULTURE Z Z Z Z Z Z 6) Adopt Farmcare Code of Practice POINT SOURCES N/A 1 7 N/A 1 7 7) 75% reduction of pollutant loads for sewage and stormwater ROAD MANAGEMENT Z Z Z Z Z Z 8) Sealing high impact roads; trapping sediment runoff; maintaining ground cover on verges Total load reduction 6 1 8 8 2 8 1 Coastal strip includes land, which due to lack of appropriate digital elevation modelling undertaken on the coastal floodplains, could be not defined within a catchment. Some overland flow will be delivered directly to coast, by not via the 4 study rivers or pathway of overland flow is not defined. As both agricultural and residential landuse utilises this component of the landscape, it is essential for inclusion. 2 Data was not available to estimate the effects of improved management of Horticulture, Roads and burning practices on grazing land. These management actions were given a qualitative rating of Zero (Z), Low (L) and were not included in the totals.

Table 4.5: Summary of acceptability, and relative effectiveness of management actions for reducing pollutant loads. Management Actions Acceptability Aggregate Local Effectiveness GBR effectiveness at Category Private at 25 years 25 years Benefit TSS TN TP TSS TN TP Point Sources Upgrade Mossman sewage Council approved N/A None Mod High None Low Low Immediate treatment plant Connect village septic Council approved Positive None Low High None None Mod Immediate tanks to Mossman STP Phase out rural residential Moderate Neutral None Low Low None None None Long-term septics Install pump-out - Tourist Required in 2007 Negative None Low Low None None None Support boats Reduce wake by river tour Moderate Neutral Mod Low Low Low None None Support operators Quarrying Moderate Negative Mod None None Low None None Long-term Reduce nutrient losses Moderate Negative Low Mod Mod None Low Low Support from Aquaculture Improve stormwater High N/A Low None None Low None None Long-term management in new areas Development sites controls Low Negative Mod None Low None None None Long-term Sugar cane Loss reduction from fertilisers High Positive None High None None Low None Immediate

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Fallow practice Moderate Positive Low None Low Low None Low Long-term Drain management Low for deep drain Negative High None Mod Mod None Low Support (deep management; deep drains; drains); moderate for Positive Immediate shallow drains. shallow (shallow drains drains) Grazing Maintain ground cover Low Negative Low Low Mod None None Low Long-term Minimise streambank erosion Low Negative Low Low Low None None None Long-term Modify burning practices Low Negative Low None None None None None Long-term Horticulture

Fertilizer and soil Low Negative Low Low Low None None None Long-term management Forestry Introduce CoP on private land Low Negative Low None Low Low None Low Long-term Riparian Riparian vegetation Low Negative Low None Low None None None Long-term Wetland restoration Low Negative Mod Low Mod Mod Low Mod Support Roads Sediment management Low Negative Low None None Low None None Long-term

From Table 4.5 Immediate category management actions are: • upgrading the Mossman STP, connecting outlying villages to it and to connect Wonga Beach to a STP (local and Shire-wide benefits). • undertaking a loss reduction program in sugar cane fields (local and Shire-wide benefits) • converting shallow drains into grassed swales (local and Shire-wide benefits)

The Support category management actions are: • reduce wake by river tour operators; • install pump-out - tourist boats; • reducing nutrient losses from aquaculture; • stabilizing deep drains to prevent bank slumping and erosion; and • improving functionality to wetlands to reduce the net loss of pollutant loads from floodplains.

These are also clearly worth pursuing if either sufficient support can be established for their introduction (speed limits on river cruises) or adequate knowledge can be developed for their implementation (nutrient losses from aquaculture and deep drain management). This plan identifies the communications efforts and the research needed to make these actions practicable.

The Long-term management actions are not accorded high priority at this stage because of the need to build support and to undertake investigation to understand how to make them effective. Investigation priorities are described in the next chapter. Thus, modification of burning practices in grazing lands may prove effective in reducing sediment losses in grazing lands if trials are conducted and all management and adoption issues are explored. As for the Support category if community support is established and/or effectiveness of the management action has been established through research activities, then the action should be implemented.

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4.9 Management Actions for Implementation Table 4.6 summarises activities needed to implement the management actions. It identifies the individual or organisation that would need to undertake the management actions and the expected time frame. The estimated cost for full implementation is between $21M to $27M over a 7-year period. Excluding the sewage effluent upgrades the estimated cost of implementation is $6-8M. A descriptive table of management actions consisting of one or more of R&D, extension and on-ground activities can be viewed in Table AD-2 in Appendix D. Clearly, the number of actions highlighted cannot immediately be implemented. Priority will be given to the actions that maximise the likelihood of achieving water quality improvement, as described in Table 4.5. Further incentives may be introduced if during annual reviews effectiveness or uptake rates are considered inadequate, or new information/technology becomes available. WQIP implementation requires a sustained commitment by Commonwealth, State and Local Government, key industry groups and the community.

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Table 4.6: Management actions, indicative timelines, approximate costs and proposed accountabilities.

# MANAGEMENT ACTIONS58 Start Finish Estimated59 Lead Agencies 60 Partnership Costs Linkage Licensed/regulated sources and activities 1 Upgrade Mossman STP (Section 4.1.1). 2007 2013 $5-6M DSC, QEPA DNRW, DLGPS 2 Connect Newell & Cooya Beaches septic systems to Mossman 2008 2013 $10-13M DSC DNRW, DLGPS STP. Connect Wonga Beach to Mossman STP or a stand-alone system (Section 4.1.7). 3 Ensure all tourist boat effluent is discharged to the Port Douglas 2010 Ongoing $10K/vessel Queensland Marine tour land-based repository for treatment. (Section 4.1.3) Transport (QT) operators, DSC 4 Ensure aquaculture discharges work towards achieving WQOs 2008 Ongoing QEPA Aquaculture for adjacent watercourse reach. (Section 4.1.2) industry 5 Investigate area in the Shire where there needs to be a Ongoing $3-5M DSC Community, prioritised replacement of rural residential septic systems. (Section 4.1.7) 5.1 Identify alternative waste disposal systems. Provide Ongoing $20K DSC information on replacement toilet systems. Establish pump-out database for compliance measures. 6 Ensure river tour operators comply with speed limits. (section Ongoing $10-12K/yr QT River tour 4.1.3) operators, DSC 6.1 Identify boat design options to reduce wave wake. Provide 2008 2013 $30K QT DSC & tour boat information to operators on objectives to maintain speed limits. operators Introduce design requirements for new operators/boats.

58 For details see sections 4.1 and 4.2./ 59 Costs are indicative to the inkind and cash contribution required to implement the action 60 This column identifies the agencies that can lead discussion to the action, but not necessarily contribute the full cost, nor at this stage commits them to undertake the actions described.

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7 Amend permits for quarries under 5,000m3 to ensure Ongoing $5K/5yr DSC compliance with the Environmental Protection (Water) Policy, 1997. (Section 4.1.4). 7.1 Undertake awareness program via site visits and inspections, Ongoing $3K/yr DSC Extraction prior to and during wet season, and distribution of guidelines. Industry 8 Maintain & review license conditions on quarries over 5,000m. Ongoing QEPA Extraction (section 4.1.4) Industry 9 Water-take and management of legal entitlements Ongoing Not determined DNRW 9.1 Introduction of metering surface & groundwater 2012 2013 Not determined DNRW extraction(excluding domestic supply) 9.2 Develop a Wet Tropics Water Resources Plan 2008 2011 Not determined DNRW Community Urban stormwater 10 Implement Erosion Control & Stormwater Management Ongoing DSC Development Development Guidelines. (Sections 4.1.5 and 4.1.6) Industry 10.1 Ensure all building contractors have, and adhere to, erosion 2007 Ongoing $5-10K/yr DSC control methods. Undertake site inspections prior & during wet season. Implement penalties system for non-compliance under the EP(Water)P. 10.2 Investigate sediment prevention and settlement plus nutrient 2008 2009 $30K (does not DSC QEPA (guidance removal or redistribution for the wet tropics. Survey urban include for DSC), runoff/erosion and recommend priority sites for remediation, installation) DPI&F (possible including installation of retention/settlement ponds. role associated with wetlands and marine plants) 10.3 Enhance stormwater management and compliance to ensure 2006 2013 Incl 9.1 & 9.2 DSC Development consistency with the Environmental Protection (Water) Policy, Industry 1997. Implement community awareness program. 11 Implement relevant State Government guidelines on reducing Ongoing Incl in above DSC FNQROC, domestic pollutants. (section 4.1.7) DNRW, QEPA Cane-growing: fertiliser management

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12 Make slow-release fertiliser available to cane growers. (Section 2006 2008 61 Cane industry NHT, Joint 4.2.1) groups, QFF, Steering Committee (disbursing funds), DPI&F, BSES, FIFA 13 Develop and implement the Douglas Shire Fertiliser 2006 Ongoing $20K for DPI&F, FNQNRM DAFF, DSC Management Strategy for the purpose of achieving the development Ltd. Cane industry WQIP’s objectives. (Sections 4.2.1 and 4.2.2) only groups 13.1 Identify barriers and incentives for uptake of alternative cane 2006 2007 Other WQIPs are DAFF, FNQ NRM, Cane industry & growing/fertilising techniques. Implement incentive for continuing this CSIRO research groups, action, commenced improved fertiliser/land management, recognising the private in the Douglas, DPI&F benefits of implementation. with work undertaken by CSIRO 13.2 Implement the Douglas Shire Fertiliser Management Strategy 2007 2013 Cane industry DAFF, NHT, to assess the effectiveness of alterative fertiliser use practices. groups (Extension DPI&F Establish trial sites throughout the Shire where N fertiliser is $150K for 3 yr Component), BSES, applied: trials CSIRO (Research - consistent with recommendations following soil and/or Component), FNQ plant tissue analysis; NRM - sub-surface and as soluble/slow release forms; - optimal with respect to timing of application and application methodology; and - at reduced rates to assess any production losses due to reduced application rates; for comparison to conventional fertiliser use practice. The Strategy will also: $30K - trial legume crops &/or soya hybrids under varying paddock conditions;

61 It is proposed these be pursued as a reef catchment-wide initiative, and therefore supported through implementation of the RWQPP.

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- promote case studies of successful drilling of legume into trash, eg Sugar Awareness Day; - investigate commercial pricing of mill mud mix; - evaluate the results of case studies with long history of analysis on fertilizer variation; and - investigate the N/yield relations of low N requiring varieties of cane. 13.3 Implement the Douglas Shire Fertiliser Management Strategy, 2006 Ongoing $180K over 3 Cane industry Research groups, through working with canegrowers in Douglas Shire to ensure yrs groups. Linkage FNQ NRM Ltd, , that fertiliser use and applications are consistent with through DPI&F DAFF, DPI&F, achievement of this WQIP’s objectives, and to this end are: Future CaneInitiative FIFA, Fertiliser - based on soil and plant analysis information; Industry - optimal with respect to timing of application and application methodology; - applied below a green trash blanket; - made sub-surface to avoid stormwater runoff losses; and - with slow release forms of fertiliser. The Strategy will also facilitate the use of fallow system and, low N or N-fixing cane varieties. 13.4 Develop effective techniques to direct drill into trash and for 2006 2009 $30K Cane industry & DPI&F, DAFF trash planting. research groups

13.5 Develop and make available information for canegrowers and 2007 Ongoing Cost Cane industry & FNQ NRM Ltd, related service industries on (a) the costs and benefits of non- incorporated research groups DPI&F, DAFF conventional fertiliser practices, (b) losses from different N into above tasks sources, (c) legume fallow cropping, (d) both costs and yield effects of fertilizer applications based on regular soil analyses, and (e) use of low N requiring cane varieties. 13.6 Provide soil testing service to determine plant requirements Incl in 12.3 Cane industry groups DPI&F other than N, which has taken into account mill mud and fallow legume. Cane growing: drain and wetland rehabilitation

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14 Develop and implement a Douglas Shire Cane Drain 2006 Ongoing $20K for Cane industry NHT, DNRW, Management Strategy, which is designed to modify drains in development groups, FNQ NRM DSC, Joint cane growing properties to achieve the WQIP’s objectives. only Ltd, Steering (Section 4.2.3) Committee (setting funding priorities), DPI&F 14.1 Establish a working group that includes Douglas Shire 2006 2007 FNQ NRM Ltd Cane industry Council, landholders and Main Roads to develop the proposed groups, DSC, Cane Drain Management Strategy. DPI&F, DMR, NHT 14.2 Develop the proposed Douglas Shire Cane Drain Management 2006 2008 $150K FNQ NRM Ltd Cane industry Strategy that will: groups, DPI&F, - identify drains in the Shire and the relative risk of sediment DSC, DMR, and nutrient loads to the Reef; DNRW, NHT - identify existing wetlands and their condition, and opportunities to construct wetlands to optimise the capture of pollutant loads and improve wetland functionality; - identify and develop drain rehabilitation measures for the Shire (including an evaluation of local application/modification of detailed recommendations from Herbert/Johnstone catchments); and - rank drain and wetland rehabilitation works according to cost-effective water quality outcomes; - cost-sharing options for deep drain design and stabilisation. 14.3 Implement the Douglas Shire Cane Drain Management 2008 Ongoing $100K/yr Cane industry NHT, DPI&F, Strategy. Implementation will include: groups, FNQ NRM DSC, DMR - field days to demonstrate stable drains; Ltd, - photo sets and procedures on drain and wetland rehabilitation; - the promotion of wetland values in the shire; and

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- a funded program of prioritised works.

Grazing management 15 Develop and implement a Douglas Shire Grazing Management 2006 Ongoing $20K DPI&F, Grazing Strategy. This will be achieved by maintaining dense industry groups, FNQ groundcover for slopes and plains through implementing Farm NRM Ltd Management Systems and GRAZING. (Section 4.2.4) 15.1 Establish a grazing study group. Determine soil losses from 2007 2009 $100K Grazing industry & FNQ NRM Ltd, hillslope erosion. Initiate research of vegetation type and research groups DPI&F management on runoff/erosion. Produce research model using published runoff data from comparable cover/slope situations. Investigate burning season effect on soil loss. Incorporate findings into Douglas Shire’s SedNet. Undertake survey of locations where productivity and stability currently occurs. Identify existing legal duty of care by graziers as a baseline to determining cost-share arrangements. 15.2 Undertake a series of field days involving land management 2007 Ongoing $50K DPI&F, Grazing FNQ NRM Ltd, decision makers, including landholders, DPI&F, NRW, NRM industry & research NRM Board Pty Ltd and downstream stakeholders. Establish trials to groups compare current practice with spring burning (moist soil) and herbicides for regrowth. Produce graphic examples and descriptions of grazing condition classes for landholder field evaluation. Promote field days and invite cooperation to trial alternative burning regimes. Establish soil loss plots on grassland and forest slopes. Horticulture and Forestry 16 Land managers adopt priority BMPs in all horticultural crops 2006 Ongoing $20K DPI&F, FNQ NRM Ltd, consistent with Farmcare. Undertake extension programme to GROWCOM, HAL DNRW. maximise adoption of priority BMPs through short courses and or equivalent. demonstrations. Facilitate incentive programs aiding landholders in the implementation of priority BMPs. (Section 4.2.7)

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17 Ensure adoption of CoP for forest activities on private lands. 2006 Ongoing $20K Forestry industry & DPI&F, DSC Investigate suitable forest species for a range of situations in research groups, (planning codes) this shire. Extension service that provides sustainable FNQ NRM Ltd techniques in establishment, silviculture, harvesting. (Section 4.2.9) Improved knowledge and science support for decision-making 18 Enhance receiving water quality model(s) 2006 2009 $50K Reef Water Quality CSIRO, DSC, Partnership DNRW, DEH 19 Ambient water quality monitoring for improved model Ongoing $15K Reef Water Quality Community, calibration/verification. Partnership Mossman Monitoring Alliance (FNQNRM Ltd, DEH, CSIRO, DNRW, QEPA, GBRMPA, DSC) 20 Maintain and enhance predictive models and decision-support Ongoing $50K Reef Water Quality CSIRO L&W, tools (SedNet and EMSS). Partnership DNRW, FNQ NRM Ltd, DEH 21 Provide science support for adaptive planning purposes and Ongoing $20K Reef Water Quality DEH decision-making. Partnership Riparian management 22 Reduce and avoid further river and creek bank erosion, through 2006 Ongoing $100K/yr River Improvement NHT, DNRW stock exclusion, establishing off-stream watering points and Trust, DSC (regulatory role), stable on-stream watering points, and vegetative and QEPA mechanical bank stabilisation. Support coordination and (regulatory role, implementation of on-ground works. (Sections 4.2.5 and 4.2.6) DPI&F (regulatory role – marine plants) 22.1 Map erosion risk areas and determine erosion rate at active 2007 2008 $50K River Improvement NRW sites. Identify and recommend stabilisation methods for each Trust, DSC

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risk class. Investigate and evaluate incentives options. Produce guide that analyses costs and benefits for appropriate management of watercourses and explains incentives and landowner obligations. Investigate cost-effectiveness of locally adapted stabilisation techniques, building on outcomes of the DSWQIP plus from the Tully & Johnstone. Review landholder riparian agreements as circulated September 2004. 22.2 Conduct field trips within Douglas and to other Shires to 2007 Ongoing $5K/2yr River Improvement DNRW demonstrate successful erosion mitigation, including off-stream Trust, DSC watering point demonstration sites. Undertake a series of field days involving land management decision makers, including landholders, DPI, DSC, DNW, EPA, NRM Board Pty Ltd and downstream stakeholders. Use existing videos on riparian rehabilitation to promote uptake to landholders. Remove or realign snags. Road maintenance 23 Develop and support implementation of road sediment action 2006 Ongoing $100K/yr DMR, DSC program for each sub-catchment as defined in the FNQROC Development Manual (current edition). (Section 4.2.8) 23.1 Develop rapid assessment method of identifying road sediment 2007 2007 $50K DMR, DSC sources and corrective action. Map and prioritise roads for sealing based on likely sediment loss to watercourses. Develop Shire road sediment control plan in consultation with landholders, including development controls. 23.2 Promote road drain management plans and engineering 2007 Ongoing $50K DSC WTMA, DMR guidelines to achieve drainage and soil stabilisation outcomes, including for steep roads. Recommend locations for application of techniques in Main Roads sediment control guidebook. Circulate leaflet to affected landholders on erosion control techniques, landowner obligations and cost-sharing (where available). Survey eroding steep private roads and promote engineering guidelines and landowner obligations.

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Monitoring 24 Implement, review and expand Douglas Shire Monitoring Strategy 24.1 Continue a load focused water monitoring program that, maintains 05/06 07/08 $90K/yr Mossman Monitoring ACTFR, present estuarine modelling, provision of expertise to interpret Alliance, Reef Water Mossman data, inform community of findings to date, maintain automatic Quality Partnership Monitoring sampling stations, provide adequate resources for collection, Alliance handling and analysis of samples. Update conceptual models 24.2 Undertake effectiveness monitoring such as, but not exclusively to, Ongoing Not determined Reef Water Quality ACTFR provision of expertise to interpret data from N-loss trial, determine Partnership effectiveness on drain remediation, & trial effectiveness of varying width riparian vegetation.

Reporting on outcomes from implementing the WQIP 25 Provision of annual, mid-term and final report that provides 2007 2013 $3K/yr DSC, FNQNRM Ltd, DEH information to the community and the State & Commonwealth Governments. Ideally the reporting structure need to be in one format that meet all constituents requirements

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4.9.1 Adaptive Management Strategy Adaptive environmental management refers to a continuous improvement model, with the purpose of responding to new knowledge and where appropriate adjusting management priorities to achieve the plan’s objective, eg reducing nutrient loads to the Great Barrier Reef. Adaptive environmental management is an appropriate management response when there are significant gaps and uncertainty in scientific knowledge, when long term management is undertaken to achieve a ‘sustainable’ outcome, and when investigations are underway to improve the knowledge base.

Key inputs to the WQIPs adaptive management approach include new information on: • the quantity of pollutants (species of Nitrogen and Phosphorous and suspended solids) as a result of improved monitoring; • the concentration of species of Nitrogen and Phosphorous and suspended solids within water bodies during ambient and events; • the change in practices needed to reduce pollutant loads and improve ambient water quality (as a percentage of landholder adoption or land mass under a change practice regime); and • the nature, timing and implications of outputs from implementation of the RWQPP and other research activities, such as under the Commonwealth’s Environment Research Facility and in developing and implementing other WQIPs in the Wet Tropics region.

To monitor and evaluate these indicators, access is needed to data and analysis from the knowledge accumulated from activities in Table 4.6 and elsewhere. This will allow improved modelling estimates and should provide greater certainty to monitoring data. As a greater understanding of the above activities is reported and reviewed (Chapter 6) there needs to be opportunity to modify priority actions and targets. In consultation with the key stakeholders a reference group, whose principal role should be to facilitate implementation of the WQIP, will make recommendations to modify an action or target.

The proposed reference group will be established in consultation with the FNQ NRM group and Australian and Queensland Governments. It will be established in the first six months of WQIP operation, and will as a minimum: - meet on a half-yearly basis; - review the operation of the WQIP and any new information or government policy with implications for the WQIP and its implementation; and - recommend and make modifications to WQIP implementation to facilitate the expedited attainment of management and environmental quality targets.

It will be vital for WQIP science providers to incorporate new data and knowledge into predictive models and decision-support tools to facilitate the reference groups deliberations. The needs for ongoing science support will be determined by the reference group.

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4.9.2 Relationship between the WQIP and the RWQPP The RWQPP provides overarching direction for the development and implementation of WQIPs. Where WQIPs are prepared, those WQIPs provide the vehicle for integrating the various strategies and actions under the RWQPP at the catchment scale.

The RWQPP will see the output of various science and policy products, for example: - Strategy D, action 4, will develop and implement local WQIP, with a highlight to support the implementation of the Douglas Shire WQIP - Strategy H, action 1, will improve the capacity for developing water quality targets for the Reef;

The implementation reference group formed for the purpose of this plan will remain appraised of RWQPP outputs, including outputs from development and implementation of other WQIPs, with a view to incorporating any technical or policy approaches into this plan and its implementation.

4.9.3 Relationship between the WQIP and the regional NRM plan. Implementation of the RWQPP, and therefore of accredited WQIPs, is considered by the Australian Government to be a priority outcome of the regional NRM programme62. Therefore management actions and investment priorities of this and other WQIPs prepared in the Wet Tropics NRM region will be targeted by the Australian Government as priorities for investment under the NHT’s regional delivery programme.

There are currently strong linkages between the WQIP and the FNQ NRM’s accredited regional NRM plan. For example: 1. The NRM plan has committed to supporting the development and implementation of WQIPs. The RWQPP indicates that WQIPs will be incorporated into regional NRM plans and implemented as a priority; 2. The NRM Board has conducted extensive consultation in determining ‘management action targets’ that will maintain or improve sustainability in this region. The WQIP actions will help implement those targets; and 3. In implementing the Board’s Plan they highlight “…the “best” investments will: • benefit high valued assets that are providing important ecological, economic, social and cultural services for the community; • address serious threats to those assets or services; and • do so in a cost-effective way.”

The catchments of Douglas Shire are small relative to most others in the Wet Tropics region. This factor, along with high levels of landowner support for uptake of best management practices means, investments in modelling, monitoring and improved land management in Douglas Shire are more likely to deliver knowledge on water quality improvement and management, and for that knowledge to be available sooner than in larger catchments.

62 pers comm

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DSC and FNQ NRM Ltd have developed a partnership to employ an officer with the role to implement the Plan. This role includes attracting resources, importing relevant knowledge and linking to other FNQ NRM Ltd processes and staff such as the Sediment Management Officer, Sustainable Agriculture Officer and officers engaged in developing further WQIPs in the wet tropics region.

It is important for the regional NRM plan to be continuously reviewed as WQIPs are prepared and/or reviewed to align its objectives and timelines.

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Chapter 5: Monitoring and Research

Summary o Water quality monitoring is needed for quantifying (in order of priority): ƒ effectiveness of management actions; ƒ current pollutant loads; and ƒ improved predictive modelling and decision-making. o Knowing the effectiveness of management actions to reduce pollutant loads will allow the plan to be modified as it is implemented. o Better estimates of current pollutant loads will provide a reliable baseline against which to measure change. o Modelling is not likely to play an important role in plan implementation and this activity has lowest priority, however, as new information becomes available modelling will be enhanced; o Monitoring “inputs” to management (uptake of BMPs, upgrades of sewage treatment plants, etc) provides an additional element to “output” monitoring. o The two water quality models used in the preparation of this plan have played more a qualitative role than quantitative due to the large uncertainties with results. The DSS containing these models is better suited for installation at the Wet Tropics NRM Board that has a regional focus and at a more acceptable scale for these models.; o Increased knowledge, coupled to adaptive management, offers the best mechanism for reducing pollutant loads. High priorities for further investigations include: ƒ implementing and evaluating options for converting shallow drains into spoon drains; ƒ implementing and evaluating sugar cane fertilizer management strategies; ƒ implementing and evaluating the cost effectiveness of leguminous fallow plants; ƒ implementing and evaluating options for deep drain stabilization; ƒ determining actual rate of stream bank erosion at active sites; and ƒ implementing and evaluating stream bank stabilization techniques.

5.1 Existing Monitoring Programs

5.1.1 Mossman Monitoring Alliance Realizing the level of commitment required for DSC to undertake the monitoring that will address load determination and effectiveness of management actions, the FNQ NRM Ltd, DSC and DEH developed an alliance with other stakeholders to implement the DS Water Monitoring Strategy. These stakeholders are DNRW, QEPA, CSIRO – L&W & CSIRO - CES. The implementation of the monitoring strategy has been modified to focus on the load determination from Mossman Catchment and addressing effectiveness from N-loss trials in the Saltwater Catchment.

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Loads Determination

ƒ The automatic samplers both upstream and downstream in the Mossman River are activated for the 05/06 wet season ƒ accurate flow estimations for the Mossman River ƒ conceptual estuarine modelling to address the understanding of the dynamics of this Mossman River estuary. The Daintree River estuary will also be modelled ƒ incorporation and interpretation of analysed results ƒ This should result in a greatly improved understanding of how land based pollution travels to the Reef Lagoon, as it will include some estimation of nutrient and sediment flow from the catchment of a river estuary.

Effectiveness

ƒ Continuation of N-loss trial by automatically sampling runoff & subsurface in a cane paddock ƒ Incorporation and interpretation of analysed results

In addition the FNQ NRM Ltd and DSC are identifying mechanisms available to restart in-stream community monitoring and in-paddock monitoring in partnership with industry.

5.1.2 Queensland Government The Queensland Department of Natural Resources, Mines and Water operates three water quality stations and four river flow stations in the Daintree catchment and one flow and water quality station in the Mossman catchment. There are no permanent monitoring stations in the Saltwater Creek and Mowbray River catchments. Water quality measurements are taken manually at fixed intervals when it is safe to access the sampling locations and so do not provide data on the high flow events required for load calculations. In addition, the ratings curves for some of these stations are no longer reliable and flows cannot be estimated accurately.

The Queensland EPA operated water quality monitoring sites on the Daintree and Mossman Rivers (as well as Coopers Creek and Hutchinson Creek to the north of the Daintree River) during the period 1994 -1999. These stations measured a wide range of ambient (i.e. low flow) water quality parameters to determine the basic water quality status of these rivers. Water quality, including nutrient concentrations, was also sampled (generally at base flow) in all four of the Douglas Shire catchments as part of a study into the state of river habitats63. However, both these water quality studies were designed for monitoring ambient water quality and neither collected the necessary flow information to allow loads to be calculated.

63 This data and other information in this section comes from Russell, McDougall and Kistle 1998. “Fish Resources and Stream Habitat of the Daintree, Saltwater, Mossman and Mowbray Catchments.” DPI, Queensland.

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5.1.3 Monitoring During the WQIP Preparation Seven automatic water-sampling stations were installed in the Douglas Shire by CSIRO as part of the preparation for this Plan. Five sampled water quality in rivers and two monitored surface and subsurface flows from fertilizer application trials on sugar cane fields64. The river monitoring stations were located: • Upper Mossman River (below the gorge); • Lower Mossman River (tidal reach); • Lower Saltwater Creek (tidal reach); • Upper Daintree River (below Baird’s Crossing); and • Lower Daintree River (above the ferry). Two fertilizer trial sites were located on a sugarcane paddock adjacent to Saltwater Creek.

The stations were equipped for real-time monitoring of: • Turbidity • Electrical conductivity (lower stations) • Height. The river stations were triggered to respond to increases in flow, based on the above parameters to collect samples during flow events of all sizes so that pollutant loads could be calculated. Water samples were analysed and determined for, • TP, TDP, FRP • NH3, NOX, TDN • TSS

However, ratings curves were not obtained for the three lower stations and so river flows could not be calculated. Consequently pollutant loads were only available for the two stations at Upper Mossman and Upper Daintree locations below the WHA.

A community monitoring program was also funded as part of the preparation for this Plan. Volunteers collected monthly grab samples for ambient sampling of sites representative of major land uses and analysed as for automatic water-sampling stations. Attempts to sample larger events were abandoned for safety reasons and because they were unable to capture samples at the specific stages of the hydrograph. The seven community sampling sites were located to provide information on water quality below specific land uses: • Grazing: Upper (leaving “forested areas”) and Lower Stewart Creek (Daintree Catchment) • Sugar: Upper Saltwater (leaving “forested areas”); Mid-Upper Saltwater (Poletti Bridge); Mid Saltwater (Miallo Bridge) • Urban: Mid Mossman (Foxten Bridge); Lower Mossman (auto-station)

A further 7 sites were monitored by the community • 4 sites at the automatic water sampling stations (excluding Saltwater Creek) • 1 located at the end of Mowbray Catchment • 1 located in Mossman township at Parkers Creek • 1 located on Cassowary Creek (Mossman Catchment)

64 Appendix B of the Douglas Shire Water Quality Monitoring Station (McJannet, et al, 2005) provides details.

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The samples could not be used to calculate pollutant loads since concurrent flow information was not available. However, they did provide a valuable record of ambient water quality that was used to check the extent to which the Shire was meeting the WQOs.

The funding for the automatic sampling and the community sampling ceased at end 2004/5 financial year.

5.2 The Water Quality Monitoring Program Monitoring is required for three purposes during the implementation of this Plan: • To monitor the effectiveness of management actions • To obtain better estimates of current pollutant loads • To provide data to improve modelling, and reduce modelling errors.

5.2.1 Effectiveness of Management Actions The most important purpose of monitoring is to determine which management actions have been effective in reducing pollutant loads. Under an adaptive approach to planning, this information can be used to retune the plan so that increased emphasis is placed on the more effective actions. The reasons for the poor results from other actions can be explored and these actions can possibly be improved. This requires that monitoring stations are located close to sites where these actions are being implemented, and that a monitoring programme is undertaken for priority management actions, and which are designed to meet adaptive management needs.

The management actions that can be expected to lead to major local changes in water quality and their locations are, according to Table 4.4: • TSS: repairing deep and shallow drains in sugar cane fields; • TN: improving fertiliser management on sugar cane fields; and • TP: upgrading point sources and repairing deep and shallow drains in sugar cane fields.

Most of the annual pollutant load is delivered during storm events, and so monitoring requires installation of automatic water quality sampling stations. CSIRO funding is available for a further year’s monitoring (2005/06) at the two automatic sampling stations currently being used to measure the effects of nutrient reduction activities in sugar cane trials. This is too costly to be feasible for monitoring the other Immediate management actions. Specific research programs around priority management actions would need to be established to quantify the effectiveness of other management actions. It is acknowledged that in many cases, such work needs to be location- specific.

The reductions in TP from effluent in the coastal strip (because of connection to Mossman STP) will be too difficult to monitor directly. However, groundwater quality and flow monitoring should be used to record changes in TN following connection to the sewerage system. Because these changes can be expected to occur fairly rapidly, this monitoring program needs to be continued for about 1 year before and 2 years after connection to the sewerage system.

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The upgrades to the Mossman STP are expected to reduce phosphorus loads significantly in the Mossman estuarine river reach. Because these loads are reasonably constant and not affected by flow events, they are well suited to ambient water quality monitoring of the effluent stream.

Since the Plan is based on reducing loads, all monitoring sites should either have ratings curves developed or be surveyed for Manning’s equation so that water quality samples can be linked to flows.

Although this purpose is the highest priority, funding has not yet been identified for special research programs, community monitoring, groundwater monitoring, or retention of the automatic monitoring stations in the sugar cane trials beyond one year.

5.2.2 Measuring Pollutant Loads Obtaining data for reliable estimates of catchment pollutant loads is the second highest monitoring priority. Reducing the errors on these load estimates will provide a more reliable base against which management actions can be measured. The automatic monitoring stations are best suited to this task since the change in concentration during flow events of different sizes and timings needs to be recorded. However, they are expensive to operate and the current five river stations cannot all be maintained.

Funding has been assessed from the Australian and State Governments, Douglas Shire Council and CSIRO for one year of monitoring and sample analysis with two automatic sampling stations in the Mossman Catchment to: • provide further data on current pollutant loads; • rate the lower catchment station for flows; • analyse and link water quality samples collected during the preparation of this plan to gauged flows; • devise more efficient sample analysis mechanism to reduce cost of collection; and • develop a conceptual estuarine model to predict the fate of pollutants between the freshwater interface and the GBR lagoon.

The Mossman stations are best suited for this purpose, since the load results from the Upper Daintree station are considered unreliable. However, it is essential that a proper rating curve be established for the upper and lower Mossman stations65. Obtaining reliable water quality data cannot be undertaken over the short term. These stations need to be maintained for a period of at least 5 years so that the range of flow events can be sampled, and reliable pollutant loads established.

If further funds became available, the upper Daintree station should be rehabilitated and a ratings curve established (or the curve for the DNRW Baird’s crossing site could be re-calibrated). This would allow the pollutant loads coming from this large region to be established with certainty.

Following an analysis of the data from the existing automatic stations, CSIRO recommend that approximately 80 – 100 samples should be taken from each

65 The lower Mossman station, being in a tidal reach, will need to be calibrated with special equipment.

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automatic station per annum. A monthly grab sample is sufficient for the ambient water quality monitoring. The differentiation between Dissolved Organic Nitrogen and Dissolved Inorganic Nitrogen would be additional information in examining critical sources.

5.2.3 Calibrating the Water Quality models The two models used in this Plan could provide only limited direction on loads leaving Douglas Shire, and how these might be affected by a range of land management practices.

This limitation was due to the lack of local data for model calibration, assumptions made about some key parameters did not apply to wet tropic conditions and the sensitivities of the models being insufficient to work effectively at the scale required.

While the figures produced by the models have significant uncertainties, the models do show direction for BMP adoption to achieve reduced sediment and nutrient export.

The nature of the models used also meant that exploring alternative scenarios and management action practices is a cumbersome and time consuming process. It may be that simpler calculations will suffice until more data has been collected, thus the SedNet and EMSS models will not be used during initial Plan implementation.

The adaptive approach to implementing this Plan means that the Plan will rely much more heavily on responding to direct monitoring of management interventions than it will rely on model predictions. With other WQIPs being developed along-side the GBR it would be expected that a higher level of data, both quantitative and qualitative, from management intervention will be available from these WQIPs to feed into the conceptual models. Consequently, collecting data to better calibrate the current models is a lower priority in this plan. Nevertheless, alternative models will be evaluated and populated with existing and likely future data with a view to assisting in the adaptive management process and in aiding with decision-making activity. A function of reference group will be the steering of appropriate information from the WQIP and other processes into implementation (Chapter 6).

A model may be required at a later stage to, for example, recalculate loads from the ungauged catchments in light of the automatic sampling data from the Mossman catchment. A more flexible, smaller scale, model may be appropriate for this work.

This Plan does not recommend investing in data collection for model calibration as a high priority. However, data collected measuring the effectiveness of management actions and estimating current pollutant loads will be used for model calibration.

5.2.4 Input Monitoring The changes in “inputs” to both point and diffuse sources need to also be monitored. Thus, the increasing acceptance of modified nutrient management practices on sugar cane fields should be recorded through surveys, and the extent of stream banks that have been rehabilitated should be recorded in Council and FNQNRM Ltd records.

This “input” information has two purposes. It can be linked to the changes in ambient local water quality (Section 5.2.1) so that a cause-effect relationship between the

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management action and the changes in water quality can be established. It can also act as a measure of plan adoption in its own right and the Management Action Targets from the NRM Plan that deals with uptake rates. Given the difficulties in interpreting a record of water quality changes in the face of climate variability and multiple changes in the catchment, the increasing adoption of BMPs and other desirable practices can be a valuable record of Plan implementation.

It is also important to track adoption rates for recommended BMPs so that governments can review, and if necessary, adjust incentives arrangements.

The three main input measures to record in this monitoring program are: • adoption of improved nitrogen management measures in sugar cane fields; • progress in rehabilitating deep and shallow drains in sugar cane areas; and • upgrades to the Mossman STP and connection of outlying villages. These input measures should be recorded every 12 months.

Funding has yet to be agreed to monitor input information although, within the sugar sector, Mossman Agricultural Services provides an extension program that addresses BMPs and has established baseline information on the current level of adoption of BMPs. The FNQ NRM Ltd within their Plan defines a monitoring and evaluating strategy for adaptive management and reporting that includes assessment of progress of their Management Action Targets. For the purpose of this WQIP, a third party monitoring programme will be established to evaluate the accuracy of the self- assessment programme.

It needs to be acknowledged that information on the effectiveness of BMPs in reducing sediment and nutrient export needs in most cases to be measured, and this work is intensive, and thus expensive.

5.2.5 Decision Support System The two models used in this plan production - Environmental Management Support System (EMSS) and SEDNET/Annex - have been incorporated into a Decision Support System (DSS) for use by Council staff. Both models are linked to a single web-based interface that has been designed for use by staff that will require appropriate training to use the interface with confidence. The models can be run through the interface to investigate the likely effects of other changes in land use or management. This interface also functions as a repository for the large amount of background information surrounding the Douglas Shire Water Quality Project.

An operational version of DSS has been installed at Douglas Shire Council and is being evaluated. The DSS requires designated personnel with appropriate skills, preferably GIS skills. It is acknowledged that the DSS can only give broadscale indications of the likely implications of catchment or sub-catchment scale management changes.

Given the limited need for models during plan implementation, the DSS would be better suited for installation at the regional NRM Board where the appropriate skills are more likely to be available and where there may be opportunities for its use in strategic NRM planning, or as a service to Douglas Shire for any strategic land use planning it may undertake.

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5.2.6 Monitoring for WQIP Review

Water quality monitoring will be needed to evaluate the WQIP. Ideally, this would be supported on an on-going basis, but competing Government priorities preclude this. However, the work of the Monitoring Alliance will see more data available to calculate current loads from estuaries to the GBR lagoon. This work provides improved baseline data on loads, which will allow recalculation of load targets.

As the WQIP draws closer to its 7-year review, this work should be repeated, to firm the baseline, and allow an understanding of the long-term impacts of management actions.

5.2.7 Reef Water Quality Partnership

This partnership between Australian and Queensland Government agencies and regional natural resource management bodies of the GBR will, through its management committee, lead strategic policy advice and program direction, and the coordination of partner activities to deliver agreed priorities. The implications of this partnership to the Douglas WQIP in terms of the relationship of monitoring and targets will be to maintain a continual dialogue by the Douglas WQIP Steering Group to the RWQP of the importance of maintaining a monitoring program that links to targets. At present the Douglas Shire has a comprehensive data-base of event concentrations, with a flow program underway to link concentrations to flow.

With the RWQP recommending priorities it is important that where relevant priorities that work outside this shire are designed so that the knowledge gained is applicable to this Plan. Also applicable would be that monitoring undertaken in the Douglas has relevance in other regions.

5.3 Knowledge Requirements Highly targeted investigation needs to be carried out to provide biophysical, social and economic information during plan implementation. This investigation, while focusing on water quality improvements, can lead to economic benefits for landholders that would improve the acceptability of the management actions.

This work is closely tied into adaptive plan implementation. The results of these priority investigation topics will be reported and reviewed annually as part of the plan review process. If the work successfully demonstrates how some Support category management actions can be made effective and if there is sufficient support for them, then they can be introduced into the plan implementation.

The necessary areas for investigation, in priority order, are: High Priority • Investigate cost-effectiveness and cost-sharing options for drain design and stabilisation;

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• Trial cost effective options for converting shallow drains into spoon drains. The design of these spoon drains is reasonably well known and this research would be aimed at ensuring that the drain design was efficient for farm use; • Trial cost effective options for deep drain stabilisation. The slopes and strengthening required and the grasses to be used to produce stable deep drains under tropical conditions needs to be established for the sediment reduction management actions to be effective. Considered a support category while undertaking investigative works in developing the Plan, quantifying the level of condition for both shallow and deep drains was not undertaken. The author consider it appropriate that both forms of drainage are needing to be addressed together; • Undertake field trials to develop sugar cane fertilizer management strategies that reduce losses in accordance with plan targets. This is the most promising source of TN reduction and needs to be supported with reliable scientific data on less soluble fertilizers, split applications, use of legume fallow crops to reduce N needs, etc. Funding should be sought to continue the use of the two automatic monitoring stations being used for these trials beyond 2006/07; • Identify landowner duty of care obligations under Australian, State or local Government laws and policies, as a baseline consideration for developing private- public cost-share arrangements for management actions; • Undertake the research needed to establish the quantitative links between different sediments and nutrient loads on components of the Barrier Reef system so that impact based Resource Condition Targets can be established, and • Further develop the economic research commenced by CSIRO linking water quality improvements to marine and freshwater benefits, including quantifying public benefits through contingent valuation and other such techniques.

Medium Priority • Establish the cost effectiveness of leguminous fallow plants in reducing nitrogen needs. Until this is known from actual trials it is difficult to introduce this practice; • Investigate actual rate of stream bank erosion at active sites. Until this information is better known it is difficult to estimate the contribution from stream banks to sediment loads in Shire rivers; • Investigate grey water reuse options under local conditions; • Investigate commercial pricing of mill mud when mixed with balancing nutrients; • Investigate cost sharing options and public benefits that go beyond duty of care of this combination of practices; • Trial different stream bank stabilization techniques for their sustainability in tropical conditions; • Establish through field experiments the loss of soil from road verges into local creeks. Until this is quantified for the wet tropics, it is difficult to develop an action plan; • Investigate condition ratings for existing wetlands in the shire; and • Investigate freshwater aquatic ecological dependence on environmental flows in wet tropical systems.

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Low Priority • Trial & document species of legume suited &/or various hybrids of soya on varying paddock conditions; • Investigate to a greater detail the cost effectiveness of legume fallow & weed management; • Investigate incentives available to growers to move from plough-out to fallow plant; • Investigate the means of harvesting legume for grain as well research more versatile trash planter; • Investigate burning season effect on soil loss; • Mapping of instability risk areas and suggested appropriate stabilization method for each risk class; • Develop rapid assessment method of identifying road sediment sources and corrective action; • Investigate cost-sharing options between local government and state for road verge improvement; • Trial geotechnical-fibres and porous cover material for steep roads/drains in tropics; • Initiate investigation into vegetation type and management on runoff/erosion from grazing hillslopes; and • Investigate and trial cheaper low energy on-site wastewater disposal systems for use in the tropics

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Chapter 6: Adaptive Implementation

Summary o Douglas Shire Council will implement the Plan in collaboration with the Far North Queensland NRM Ltd, State government agencies and industry groups. Funding will be sought from Federal-State programs such as NHT2 and from state agency programs. o To oversee the implementation of the WQIP a local reference group will be formed with linkages to the FNQ NRM Ltd. o Adaptive Implementation includes strategies to achieve the goals of the Plan (i.e. reductions in pollution export from Douglas Shire) in changing circumstances. o There are current commitments for a limited number of the priority implementation, monitoring, and research activities. Funded priorities include: ¾ Upgrades to sewage treatment and connection of unsewered villages (Douglas Shire Council) ¾ Continuing sugar cane nutrient loss management trials for one year (CSIRO) ¾ A Monitoring Alliance between Local, State, Federal & Wet Tropic NRM Board ensures a 2005/06 wet season monitoring program o Notable unfunded priority activities include: ¾ Sugar cane nutrient reduction activities ¾ Sugar cane shallow drain improvements ¾ Monitoring effectiveness of management actions ¾ Research into drain stabilization techniques

To implement a plan that is multi-tasked, over a 7-year period, requires commitment by Commonwealth, State and Local Government, key industry groups and the community. This chapter outlines the level of commitment to date, plus explain strategies to address non-committed tasks identified in the WQIP. Table 7.1 provides a summary of committed tasks.

Work undertaken in the interim projects that were implemented concurrently with the WQIP identified resource protection issues and areas of concern within the Shire. These projects highlighted the issues of stabilisation of built drainage lines, reducing Nitrogen losses, BMP extension within the agricultural sector and STP upgrades as priority issues. The stabilisation of riparian areas and re-establishment of functional wetlands/sink is also a priority issue if the objective of the WQIP is linked to the objective of providing good stream health within the Shire.

The Final Reports of these interim projects can be viewed at www.dsc.qld.gov.au, while the summary of each is provided in Appendix B.

Monitoring of identified task implementation will be the responsibility of a local reference group that will be supported by an Implementation Officer. The DSC, FNQ NRM Ltd, Queensland and Australian Government identify this plan as a blueprint for this shire in improving water quality and to use the Douglas Shire experience in developing WQIP’s in other regions.

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The reference group will comprise representation of key stakeholders, with the principle selection criteria based on the individuals commitment to sustainable principles for their industry and an interest in devolving information to and from their industry. Their role is defined by implementing the plan to the best of the group’s capability and provides strategic advice to the Implementation Officer in,

• Tasks committed in the WQIP • Seek opportunities for implementing uncommitted WQIP tasks • Monitor progress of the WQIP • Report on progress of the WQIP • Linkage of WQIP outcomes with biodiversity outcomes.

The largest investment to reducing pollutant loads entering the Great Barrier Reef lagoon within this Plan is the upgrade of sewage services in the shire. Over the next 6-7 years Douglas Shire Council will invest an estimated $15M-$19M to this upgrade. State Treasury will also be a substantial investor in this works program. Once completed there will be a reduction of 25.3 tonnes/year of TN and 11.9 tonnes/year of TP.

Douglas Shire Council also has a program of road sealing and verge conversion (to allow for slashing) that has been ongoing and is budgeted for continuation. The council will also employ a Sustainability Officer for promotion and accreditation in the Greenglobe program, plus participation within Cities for Climate. This officer will also provide continual support of sustainable management options for DSC core activities.

The River Improvement Trust has provided support for remediating priority sites identified in the WQIP process and have committed funds to a number of these sites for the 2005/06 works program. This support is likely to continue in partnership with Commonwealth Initiatives such as Envirofund and National Water Initiative.

Queensland and Australian Government have committed resources to undertake a wet season water-monitoring program in partnership with DSC, CSIRO and FNQ NRM Ltd. The commitment is for the 2005/06 wet season and will contribute data to the two previous wet seasons. Ideally a further two years of monitoring would reduce the uncertainty factor in estimating loads from monitored data.

Reducing losses of dissolved N has been identified in the Immediate Category to implement, based on effectiveness and acceptability. CSIRO will continue the infield trial to map N-losses for the next wet season. Separate work that CSIRO is undertaking in the wet tropics, including Douglas Shire is the researching of N- application. It is expected that the knowledge gained from these investigations will be rolled out to the stakeholders via the extension programs outlined in Table 7.1. Extension services by Mossman Agricultural Services will continue to inform growers on appropriate strategies to reduce N-losses. The scenario of increasing the levy on cane has been proposed to growers by MAS, with general support. This increase in levy will go towards increase availability of soil testing, legume seed supply and for conversion to wider spacing. Access sought for resources from funding through DAFF – Regional and Community Project (Sugar Industry reform Program) would enhance the capacity in delivery by complimenting this levy.

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The stabilisation of shallow drains (Immediate) and stabilisation of deep drains (Support) are unfunded and will require appropriate input from the reference group to seek funding. It has been identified that there is a high public benefit, yet a negative on-farm economic benefit to address stabilisation of drains. It is therefore appropriate to seek public monies from State or Commonwealth Initiatives to reduce the erosion of drains, plus Council’s input to appropriate practices and maintenance of Shire’s drains. Industry groups require listing drain remediation higher on their agenda to effectively address this issue.

Figure 7.1 is a schedule outlining committed tasks over the life of this Plan. This schedule will continually be updated as opportunities of non-resourced management actions are realised.

As FNQ NRM Ltd rollout the Regional Investment Strategy (RIS) opportunity exists for further investment into the shire for water quality/natural resource management issues. The placement of a FNQ NRM Officer (Implementation Officer) in the shire to address the WQIP places the shire in a position to target WQIP uncommitted priority actions to the RIS where applicable such as addressing drain stabilisation. Excluding investment in the point source upgrades, committed investment into the shire is approximately $1. 6M and does not include private investment from individuals and businesses undertaking appropriate management practices. Unfunded priority activities – from Table AD-2 - include:

Implementation Activities • Sugar cane nutrient reduction activities beyond 2005/2006 • Sugar cane shallow drain improvements

Monitoring Activities • Monitoring effectiveness of connection of outlying villages to Mossman STP and commissioning of Wonga Beach STP. • Monitoring effectiveness of sugar cane nutrient loss reductions • Monitoring effectiveness of shallow drain rehabilitation • Monitoring of ‘input’ information (Mossman Agricultural Services do undertake this as part of their extension services to the sugar industry)

Knowledge acquisition • Nutrient loss reduction trials in sugar cane beyond 2005/2006 • Trial cost effective options for deep drain stabilization • Trial cost effective options for conversion of shallow drains • Economic investigation that links water quality improvements to marine and freshwater benefits.

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Table 6.1: Commitments to WQIP implementation. Task Accountability Period Budget Estimate and Contributions Action Implementation WQIP DSC 2005-06 Partnership funding for Implementation Officer ($40,000). Implementation Governments1 2005-07 Partnership funding for Implementation Officer ($60,000). Upgrade Mossman DSC 2006-11 Upgrade sewage treatment to tertiary level, $5-6M. STP Connect villages to 2006-11 Connect Newell & Cooya Beach to Mossman STP, $6-8M STP (40% State Treasury contribution to a component of above budget) Connect Wonga 2007-11 Upgrade present septic systems to STP Beach to STP $4-5M if connected to Mossman STP; $6-7M if reticulated in Wonga Stormwater DSC ongoing Council to ensure stormwater from new developments, building sites and extractive industries management (under DSC Extractive Permit) meets DSC Erosion Control and Stormwater Management Manual, through consultation & compliance. $15,000. 2005-11 Construction and maintenance of Shire’s drainage network, applying Best Management Practice in drainage management ($450,000) Road management DSC 2005-11 Council road sealing program $200,000. Conversion of verges/aprons for slashing access. $50,000. QDMR 2005-11 Main road maintenance of verges. Budget estimates not available. Sustainability Officer DSC 2005-06 Capacity building within DSC for sustainable management within Council, plus contribution to Greenglobe & Cities for Climate Programs, $35-45,000/annum, plus oncosts Wetland and riparian DNRW, DSC. 2005-06 Undertake works as identified in WQIP (Project 4) as per River Improvement Trust works restoration schedule, $100,000. Governments1 & 2005-06 Rehabilitate wetlands, $200,000 (funding pending). DSC DSC 2005-06 Operation of Plant Nursery & planting team, $110,000. Governments1 2005-08 Assistance for plant propagation for peri urban plantings, riparian, drainage & wetlands (under the program revegetation for Community & Climate Program, $50,000. Extension – sugar QDPI Ongoing Extension services, including monitoring BMP uptake, $30-40,000. Extension – cocoa Ongoing Extension services in the establishment of alternative sustainable cocoa plantations. $7,000. Extension – grazing QDPI 2005–06 Provision of Grazing Land Management Package. $20,000.

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Monitoring Current pollutant load QDNRW 2005/06 Hydrographer, data collection and analysis, 2 automatic water quality sampling stations monitoring ($25,000). QEPA 2005/06 Water quality sample analysis from 2 stations (Supply Acoustic Doppler equipment, $10,000. EPAQEPA - $10,000). DSC 2005/06 Maintenance of 4 automatic water quality sampling stations ($8,000). DEH 2005/06 Cash contribution to a multi-agency Monitoring Alliance ($50,000). CSIRO 2005/06 Estuarine modelling program for the Mossman Catchment (up to $50,000). BMP monitoring QDPI, Ongoing See Extension – Sugar, Cocoa & Grazing. Governments1 Knowledge Acquisition Sugarcane nutrient CSIRO-CSE 2005/06 Collection and analysis from automatic water quality sampling stations, including lysimeter reduction trials analysis ($10,000). Sugarcane Nitrogen 2005/06 This research project is undertaken in the wet tropics including DS. ($50,000 CSIRO inkind). application Reporting/review Annual Review DSC/Governments1 Annual A role of the DSC Implementation Officer (approximately $3,000/yr) Mid & Full-term 2008 & Costing not available Reviews 2011 1 denotes delivery of Qld and Australian Government contributions through FNQ NRM Ltd.

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Figure 6.1: Implementation Schedule for WQIP

2005/06 2006/07 2007/08 2008/09 2009/2010 2010/2011 2011/2012 Action Implemetation (Immediate Actions only) Upgrade Mossman STP Connect Cooya, Newell & Craiglie to STP Provide an STP connection for Wonga Beach residents Reduce nutrient losses from sugar cane fields Rehabilitate shallow drains in sugar cane fields Extension of BMPs within the sugar industry1,2 Extension of BMPs within the cattle industry1,2 Extension of BMPs within the cocoa tree crop1,2,3

Monitoring Management Action effectiveness Current pollutant loads Monitoring 'input' information on management actions

Research (Priority research) Trial deep drain stabilization Trial cost effective options for shallow drains Field trials of sugar cane fertilizer management Economic research linking water quality with marine benefits

Reporting and Review Annual report 7-year report Annual review 7-year review 1 Commitment can be only identified for set period due to non-guarantee of resource allocation 2 While BMP delivery may not have a focus on water quality, a significant number of BMPs (including business planning have both direct and indirect benefit to water quality 3 A potentially alternative/supplementary tree crop in this shire

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Chapter 7: WQIP Reporting and Review

Summary o Annual reports will be produced describing progress in plan implementation. o The annual reports will be provided for public comment and will contribute to region wide reporting on progress on delivery of the Region’s Management Action Targets (within the Regional NRM Plan); o The WQIP will be reviewed annually based on progress articulated within the annual reports, and feedback from stakeholders and the public. These reviews will recommend changes in the plan’s implementation, if warranted, based on this information. These changes may include changes in the implementation of the management actions, and adoption of new management actions and MATs. o There will be a significant review after 3 years to assess progress in meeting the load reduction targets and to assess the effectiveness of the management actions based on a special monitoring program. A revised plan will be drawn up as a result of this review and repeated after 7 years (a full cycle of the DSWQIP).

7.1 Reporting Douglas Shire Council, in collaboration with Queensland and Australian Governments, will be responsible for producing short annual reports describing progress with implementing the WQIP. A partnership with Wet Tropics NRM Board will provide to Council the resources to undertake these reports, which ideally will be in a SoE format compatible with those used by other Wet Tropic areas in FNQ, the Regional NRM Board’s reporting requirements and those for Queensland and Australian Governments.

The annual reports will be used to inform governments, the Wet Tropics NRM Board, stakeholder groups and the general public about progress in implementing the plan, and any adjustments that may be required to achieve the WQIP’s environmental targets. The reports will be used in the annual reviews of the plan. The reports will contain:

• Progress in implementing the management actions in Chapter 4 of this plan; • Results of the monitoring programs (for assessing management actions and establishing baseline loads with improved reliability) described in Chapter 5 of this plan; • Results of research and extension activities described in Chapter 5 of this plan and their relevance to implementing the Plan; • Results of consultations with stakeholders and community groups about implementation of management actions and outcomes of the research activities; • Any activities of government agencies (including NRM Board), stakeholder groups that affect water quality in the Shire; and • Land use changes that have the potential to affect water quality in the Shire.

The reports will be distributed to the Wet Tropics NRM Board, Australian Government Department of Environment and Heritage, Queensland Government state agencies and the Great Barrier Reef Marine Park Authority. They will be made

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available to the general public and stakeholder groups through public libraries in the Shire and through the Council’s website.

Council will seek to conduct a public meeting each year to discuss the report and receive feedback from the interested public. This feedback will be recorded and used in the annual review of the plan.

The report will be structured for contribution to region-wide reporting by FNQ NRM Ltd of progress of the region’s Management Action Targets

7.2 Review of WQIP

7.2.1 Annual reviews As part of the adaptive approach to implementing the WQIP, there will be an annual review of progress in implementing the plan for the purpose of adapting the plan implementation in light of further information. These reviews will be conducted by Douglas Shire Council and the Wet Tropics NRM Board (FNQ NRM Ltd). Queensland government agencies, the Federal Department of Environment and Heritage and other interest groups, such as the Mossman Agricultural Service and industry representatives, would be invited to attend.

These reviews will be held after the annual report is published and feedback has been obtained from the public and stakeholder groups. The reviews will consider the flow and water quality monitoring results, progress with implementing the actions outlined in the WQIP and the results of research and extension conducted as part of the WQIP. Actions categorised as Support or Long-term in the plan will be re-assessed and a decision will be made on implementing actions that show potential to reduce loads of the pollutants of concern in either local areas or catchment-wide and they have received sufficient stakeholder support.

7.2.2 Mid-term review A mid-term review of the WQIP will be held during 2009 to assess progress in reducing pollutant loads and draft the next phase of the WQIP. The objectives of the review are to: o Review current and WQIP loads in the Shire Rivers using additional monitoring data and improved water quality models; o Assess the cost-effectiveness of WQIP management actions, the rate of uptake of management actions by landowners and mangers, including any modifications to those actions or staging of those actions as a result of the adaptive management approach; o Assess stakeholder and public response to the implementation of the WQIP, including: ¾ Perceptions of and benefits from improvements in water quality ¾ Effects of management actions on productivity o Identify additional effects on water quality including: ¾ land use changes since the WQIP was adopted, ¾ changes in administrative arrangements, public policy and incentives at the regional, State or Commonwealth levels, ¾ proposed infrastructure investments, ¾ the nature and relevance of new codes of practice for industries.

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o Assess the results of research undertaken since the WQIP was adopted o Evaluate and incorporate outputs from the RWQPP and other WQIP’s; o Recommend modifications to the WQIP including: ¾ Changes to the management actions ¾ Any changes to the incentives structure for BMP uptake ¾ Modifications to oversight and implementation arrangements ¾ Funding for implementation ¾ Research priorities ¾ Reporting and reviewing arrangements

The above is not an exhaustive listing of review activities.

Data from the baseline monitoring program will be used to provide revised estimates of the current pollutant loads using improved water quality models, if possible. The monitoring results will be used to assess whether load targets set in this plan are being met. The effects of climate variability as well as other changes occurring in the Shire can mask this assessment, and the review will need to incorporate these exogenous factors where possible.

The effectiveness of the management actions will be assessed using any relevant research and monitoring that has been conducted. The rates of adoption of the management actions will also be considered in this assessment, as well as any options for increasing incentives for uptake.

Comments will be sought from implementing agencies, stakeholders and the interested public on the practicalities of implementing the management actions. The review will be conducted within the context of the Wet Tropics Management Plan. Experience from other WQIPs will also be used in reviewing the Plan.

In the context of meeting Receiving Water Quality Targets to maintain and improve the condition of the GBR the review report may recommend changes to the WQIP to its full cycle, including possible changes in targets, management actions and monitoring arrangements as well as administrative changes in implementing the plan. The intent of this Plan is to achieve changes in resource condition that will assist in the ecological sustainability of the GBR, therefore any recommended change should reflect new understanding of pollution exports or water quality requirements of reef ecosystems. The review report will be made public for comment before being finalised and submitted to Douglas Shire Council.

7.2.3 Full Review It is proposed that for the 7 years (full cycle) review of management action targets and achievement in meeting the WQIP targets is undertaken with key stakeholders to assess feasibility of a DSWQIP Mark Π.

For the full Review, it is essential that up to date water quality data is available. Thus, as a minimum, a follow-up monitoring cycle will need to be conducted in the wet season of 2011-2012, to provide a basis for measuring changes (if any) to sediment and nutrient export rates from the Shire, and possibly additional information to that collected in the 2005-6 wet season.

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Water quality will be monitored for the full review, subject to a funding partnership, to provide a comparison with current data. While ideally, water quality monitoring should be an on-going priority, it is recognised that competing priorities may preclude more than comparative monitoring for the 7-year reviews.

In addition to the above, FNQ NRM Ltd will require input from this Shire into the NRM Board’s processes in reporting against Management Action Targets and Resource Condition Targets.

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References Anon (2003). Establish program for upgrading significant point sources of sediment and nutrient discharge. QEPA & DSC report to the Douglas Shire Water Quality Improvement Plan, Project Three. Bartley, R., Henderson, A., Hotham, H., Hartcher, S. and Wilkinson, S. (2004) Using the SedNet model for scenario analysis within the Douglas Shire Catchment: final results and evaluation of the model. Report to Douglas Shire Council and the Department of Environment and Heritage, Canberra. http://www.clw.csiro.au/publications/consultancy/2004/Patterns_of_Erosion_ Sediment_Nutrient_Transport.pdf Chiew, F., Scanlon, P., Vertessy, R. and Watson, F. (2002) catchment scale modelling of runoff, sediment and nutrient loads for the southeast Queensland EMSS. Cooperative research Centre for Catchment hydrology, Technical Report 02/1, February 2002. McKergow, L.A. Prosser, I.P., Hughes, A.O. and Brodie, J. (2005a) Sources of sediment to the Great Barrier Reef World Heritage Area. Marine Pollution Bulletin, 51, 200-211. McKergow, L.A. Prosser, I.P., Hughes, A.O. and Brodie, J. (2005b) Regional scale nutrient modelling: exports to the Great Barrier Reef World Heritage Area. Marine Pollution Bulletin, 51, 186-199. Murray, N., Cuddy, S.M, Rahman, J., Hairsine, P., Chiew, F., Grayson, R. and Seaton, S. (2005) EMSS User Guide. Client Report for the Cooperative Research Centre for Catchment Hydrology. CSIRO Land and Water, Canberra. Newham, L.T.H., Norton, J.P., Prosser, I.P., Croke, B.F.W., Jakeman, A.J. (2003) Sensitivity analysis for assessing the behaviour of a landscape based sediment source and transport model. Environmental Modelling and Software, 18, 741- 751. Prosser, I.P., L. Karssies, R. Ogden and P.B. Hairsine. (1999). Using buffers to reduce sediment and nutrient delivery to streams.. Chapter in Price, P. and S. Lovett (eds) 1999. Riparian Land Management Technical Guidelines, Volume 2: On ground management tools and techniques, LWRRDC Canberra. http://www.rivers.gov.au/acrobat/techguidelines/tech_guide_vol2_chapd.pdf Renard, K.G., Foster, G. A., Weesies, D.K., McCool, D.K., and Yoder, D.C. (1997) Predicting soil erosion by water: A guide to conservation planning with the Revised Universal Soil Loss Equation. Agriculture Handbook 703, United States Department of Agriculture, Washington DC. Roth, C. H., Visser, F., Wasson, B., Prosser, I., and Reghenzani, J. (2003) Quantifying and managing sources of sediment and nutrients in low-lying canelands. CSIRO Land and Water Technical Report 52/03. http://www.clw.csiro.au/publications/technical2003/tr52-03.pdf Vertessy, R., Watson, F., Rahman, J., Cuddy, S., Chiew, F., Scanlon, P., Seaton, S. and Marston, F. (2001). New software to help manage river water quality in

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the catchments of the south-east Queensland region. In: Rutherfurd, I., Sheldon, F., Brierly, G. & Kenyon, C. (eds). Proc. 3rd Australian Stream Management Conference, Brisbane 27-29 August, 2001, pp. 611-616. Visser (2003) Sediment budget for cane land on the Lower Herbert River floodplain, North Queensland, Australia. Unpublished PhD Thesis, Australian National University, Canberra. Watson, F., Rahman, J., and Seaton, S. (2001). Deploying environmental software using the Tarsier modelling framework. In: Rutherfurd, I., Sheldon, F., Brierly, G. & Kenyon, C. (eds). Proc. 3rd Australian Stream Management Conference, Brisbane 27-29 August, 2001, pp. 631-637.

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Appendix A Environmental Values and Water Quality Objectives for Douglas Shire Waterways

Table A.1. Water quality guidelines/objectives for each environmental value (based on local reference data and NWQMS)

Environmental Values Water quality guidelines/objectives for each Environmental Value Water Indicator type TN NOxN NH4-N TP PO4 TSS Turbidity Secchi Chl a mg/L NTU m :g/l Aquatic High All Assess existing conditions in individual rivers or reaches. WQ objectives are set based on no Ecosystems Conservation change from existing values: i.e. no change in median and no change in outlying upper and Value Systems lower percentiles. WQ data is available to specify these 20, 50 and 80th percentiles for the Daintree and Mossman Rivers Slightly to UP1 0.150 0.030 0.006 0.010 0.005 N/d 6 n/a 0.6 Moderately LOW1 0.240 0.030 0.010 0.010 0.004 N/d 15 n/a 1.5 Disturbed Estuary1 0.250 0.030 0.015 0.020 0.005 N/d 10 1.0 3 systems OC1 0.140 0.002 0.002 0.020 0.003 N/d 1 N/d 0.6 Highly All Assess existing WQ at the highly disturbed test site. Initial objective is to ensure no Disturbed deterioration from this. Long-term objective is to attain the slightly to moderately disturbed Systems objective value. Intermediate objectives can be set based on (a) 95%ile of reference values from a slightly disturbed reference site or (b) on references values from another site that is highly disturbed but that is nevertheless in measurably better condition than the test site. Primary Irrigation 5.0002 0.0503 Industries Stock Water 4004 Aquaculture UP/LOW 505 1.05 0.1005 405 Estuary 1005 1.05 0.0505 755 Coastal 1005 1.05 0.0505 105

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Human n/a n/a n/a n/a n/a n/a n/a n/a Consumption Recreation Primary 10 0.0106 >1.27 & recreation Aesthetics Secondary n/a n/a 0.0106 n/a n/a n/a n/a n/a Recreation Visual n/a n/a n/a n/a n/a n/a < 20% < 20% Appreciation change change Drinking Raw water 108 0.5 5 Water supply Industrial Industrial uses n/a n/a n/a n/a n/a n/a n/a n/a Uses Cultural & Cultural and n/a n/a n/a n/a n/a n/a n/a n/a Spiritual spiritual values

Notes: UP = Upland stream (freshwaters); LOW = Lowland stream (freshwaters); Est = Estuaries; OC = Open coastal; n/a = not applicable; N/d = no data 1 based on water quality at largely un-impacted reference sites 2 Compatible with ensuring no impacts on crop yield 3 To prevent algal bloom in irrigation water leading to clogging of equipment 4 Based on preventing toxicity to livestock 5 Prevention of various toxicity impacts on cultural species 6 Unionized ammonia 7 Clarity level to minimise risk of physical injury 8 To prevent toxic effects on infants

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Table A.2: Summary of EVs and WQOs for each segment of Douglas Shire waterways

Total Turbidit TN NO N Ammon TP PO TSS Secchi Chl a x 4 y ia N mg/L NTU m μg/L Daintree River: Aquatic ecosystems Maintain existing water quality (20th, 50th and 80th percentiles), habitat, biota, flow and riparian Freshwaters in natural areas th th Visual appreciation areas. (Refer to Appendix D in Queensland Water Quality Guidelines for details.) The 20 , 50 Drinking water and 80th percentiles of existing water quality for Daintree freshwaters are given below: Cultural and spiritual values 0.090 0.010 0.003 0.005 0.003 <1 <0.5 0.120 0.015 0.004 0.007 0.004 N/d 2 N/d <0.5 0.150 0.030 0.006 0.010 0.005 5 0.5 Aquatic ecosystems Stewart Creek in developed Stock water freshwater areas Human consumption 0.240 0.030 0.010 0.010 0.004 N/d 15 n/a 1.5 Visual appreciation Cultural and spiritual values Aquatic ecosystems Daintree River in developed Stock water freshwater areas Human consumption 0.240 0.030 0.010 0.010 0.004 N/d 15 n/a 1.5 Visual appreciation Cultural and spiritual values Aquatic ecosystems Maintain existing water quality (20th, 50th and 80th percentiles), habitat, biota, flow and riparian South Arm reach th th Human consumption areas. (Refer to Appendix D in Queensland Water Quality Guidelines for details.) The 20 , 50 Secondary recreation and 80th percentiles of existing water quality for Daintree estuarine waters are: Visual appreciation 0.110 0.002 0.005 0.010 0.002 2 2 1 Cultural and spiritual values 0.130 0.015 0.010 0.015 0.003 N/d 5 1.5 2 0.250 0.030 0.015 0.020 0.005 10 1.0 3

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Total Turbidit TN NO N Ammon TP PO TSS Secchi Chl a x 4 y ia N mg/L NTU m μg/L Aquatic ecosystems Daintree River estuary Human consumption Secondary recreation 0.250 0.030 0.015 0.020 0.005 N/d 10 1.0 3 Visual appreciation Cultural and spiritual values

Saltwater Creek: Aquatic ecosystems Maintain existing water quality (20th, 50th and 80th percentiles), habitat, biota, flow and riparian Freshwaters in natural areas Visual appreciation areas. (Refer to Appendix D in Queensland Water Quality Guidelines for details.) Note: there is Drinking water insufficient information available to establish current water quality for these waters. Refer to Cultural and spiritual values Appendix D in Queensland Water Quality Guidelines for details on how to establish a minimum water quality data set for deriving local 20th, 50th and 80th percentiles. Aquatic ecosystems Freshwaters in developed Primary recreation areas 0.240 0.030 0.010 0.010 0.004 N/d 15 n/a 1.5 Visual appreciation Cultural and spiritual values Aquatic ecosystems Estuarine “saltwater” Human consumption reaches 0.250 0.030 0.015 0.020 0.005 N/d 10 1.0 3 Secondary recreation Cultural and spiritual values Mossman River: Aquatic ecosystems Maintain existing water quality (20th, 50th and 80th percentiles), habitat, biota, flow and riparian Freshwaters in natural areas th th Primary recreation areas. (Refer to Appendix D in Queensland Water Quality Guidelines for details.) The 20 , 50 Visual appreciation and 80th percentiles of existing water quality for Daintree freshwaters are given below: Drinking water 0.090 0.010 0.003 0.005 0.003 <1 <0.5 Cultural and spiritual values 0.120 0.015 0.004 0.007 0.004 N/d 2 N/d <0.5 0.150 0.030 0.006 0.010 0.005 5 0.5

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Total Turbidit TN NO N Ammon TP PO TSS Secchi Chl a x 4 y ia N mg/L NTU m μg/L Aquatic ecosystems Freshwaters in developed Primary recreation areas Visual appreciation 0.240 0.030 0.010 0.010 0.004 N/d 15 n/a 1.5 Industrial Cultural and spiritual values Aquatic ecosystems Estuarine “saltwater” Human consumption reaches Secondary recreation 0.250 0.030 0.015 0.020 0.005 N/d 10 1.0 3 Visual appreciation Cultural and spiritual values Mowbray River: Aquatic ecosystems Freshwaters in developed Stock water area upstream of national 0.150 0.030 0.006 0.010 0.005 N/d 6 n/a 0.6 Visual appreciation parks Cultural and spiritual values Aquatic ecosystems Mowbray River in national Primary recreation parks 0.150 0.030 0.006 0.010 0.005 N/d 6 n/a 0.6 Visual appreciation Cultural and spiritual values Aquatic ecosystems Freshwaters in developed Primary recreation areas downstream of 0.240 0.030 0.010 0.010 0.004 N/d 15 n/a 1.5 Visual appreciation national parks Cultural and spiritual values Aquatic ecosystems Estuarine “saltwater” Human consumption reaches 0.250 0.030 0.015 0.020 0.005 N/d 10 1.0 3 Secondary recreation Cultural and spiritual values

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Near Coastal Waters: Aquatic ecosystems Open Coastal (To State limit Human consumption i.e. 3 nautical mile [approx Primary recreation 5km]) (I) Secondary recreation 0.140 0.002 0.002 0.020 0.003 N/d 1 N/d 0.6 Visual appreciation Industrial Cultural and spiritual values

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Appendix B. Water Quality Models Two water quality models (EMSS and SedNet) were applied within this project to simulate the effects of the proposed management actions. These two models have been applied to provide greater flexibility for the description of pollutant generation and transport processes within the catchment. This has allowed a choice of the model most appropriate for describing different land use types (e.g. natural forest, agriculture). In some cases, management actions could only be described by one of the models. EMSS and SedNet (and the associated ANNEX model) are briefly described below but for more detailed descriptions we refer readers to the references cited in the following sections. EMSS The Environmental Management Support System (EMSS) (see Chiew et al., 2002) is a spatially explicit model for estimating pollutant (total suspended solids, TSS; total nitrogen, TN; and total phosphorus TP) delivery from catchments and investigating the effects of land use or management changes within them. The modelling environment and an overview of the EMSS model components are described in Watson et al. (2001) and Vertessy et al. (2001) respectively. Details of the application and use of EMSS can be found in Murray et al. (2005). EMSS is a hydrologic based, semi-distributed parameter, regional water quality model. It has the capacity to predict daily runoff, and daily loads of total suspended sediment, total nitrogen and total phosphorus from sub-catchments, interlinked within a river network. Users of the EMSS can manipulate climate, land use, land management, riparian management and point source inputs to the model to ascertain their effect on runoff and pollutant loads. EMSS is classified as a ‘distributed parameter’ model, calibrated to local conditions. It requires an input data layer of elevation to produce a node-link network of sub catchments and streams. Data layers of rainfall and potential evapotranspiration time series provide climatic inputs to the rainfall runoff component (SIMHYD; see Chiew et al., 2002), which is calibrated to observed flow (see A.1 below). The stream flow concentration of pollutants, derived from the various land use types, is calibrated to observed values of event mean concentration (EMC) for runoff events, and dry weather concentrations (DWC) for base flow conditions (see A.2 and A.3 below). These are spatially distributed across the landscape according to a land use map, and are adjusted with respect to an ‘erosion hazard index’ derived from the Universal Soil Loss Equation (RUSLE; Renard et al., 1997) parameters. Riparian vegetation is described as a pollutant sink, thereby reducing sediment loads in streams. SedNet (and ANNEX) SedNet (the Sediment River Network model) and the associated ANNEX (Annual Network Nutrient Export), are a set of modelling programs that were developed to construct catchment sediment and nutrient budgets (Prosser et al., 2001; Newham et al., 2003). Compared to EMSS, these models aim more towards describing the physical processes associated with pollutant sources and sinks on the land surface and within streams. The models report average annual pollutant export, driven by a representation of annual climate derived from a long-term record (typically 100 years; in the case of this study, up to 90 years). The sources of sediment described are soil erosion by hillslope surface processes (RUSLE; Renard et al., 1997), gully/drain erosion and riverbank erosion. For this study, we have described drains as a modified gully (A.4 below). ANNEX, the module within SedNet which estimates TN and TP

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loads, assumes that all nutrients are associated with the clay fraction of the generated TSS. The application of ANNEX within the Douglas Shire is described in detail by Bartley et al. (2004). Pollutant sinks described by these models include channel and flood plains where sediment is deposited as flow velocities decrease. The model is also capable of assessing the implications of changes in land management practices on downstream water quality using an annual time step. Large scale application of the SedNet and ANNEX models to all of the Great Barrier Reef Catchments are described in McKergow et al., (2005 a and b).

B.1 Comparison of the rainfall periods considered by EMSS and SedNet For computational reasons we chose to use the simulation period for EMSS from 2 January 1994 to 31 July 2003 as a representative rainfall period for all simulations. To check that this period has similar rainfall characteristics to the historical record (used by SedNet) we compared the daily rainfall record of the Mossman station (record available 10 February 1910 to 31 July 2003) to the representative period. The two sets of data are presented in the Figure B.1.

Mossman Daily Rainfall Comparison to 1994-2003 to 1910-2003 records

700

600 1910 to 2003 500 1994 to 2003

400

300

Daily rainfall (mm) 200

100

0 0.001 0.01 0.1 1 10 30 50 70 90 99 99.9 99.99 Probability of excedence

Figure B.1 Comparison of probability of excedence of the rainfall events used as long-term input to SedNet (1910 to 2003) and the shorter term (1994 to 2003) used for EMSS. The number of no rainfall days in each record is identical at 70 percent. Also the daily rainfall totals of the events with a probability of excedence greater than 0.1 percent are near identical. The only significant divergence between the two distributions occurs for the very infrequent events that are exceeded <0.1 percent of days. In the longer record there are five days with rainfall totals greater than 420 mm that are not present in the sample record. The largest of these is 742.7 mm that occurred on 31 March 1911. In the sample record the highest daily rainfall was 420.6 mm that occurred on the 6 March 1996. Overall it is judged that the 10-year sample used

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adequately represents the historical record. It is possible to further check this adequacy by comparing key outcomes of varying the rainfall record input.

B.2 - Rainfall runoff calibration of EMSS The characteristics and calibration SIMHYD, the rainfall runoff model used EMSS, are described in detail by Chiew et al. (2002). The application of SIMHYD within EMSS requires calibration for ‘forest’ and ‘non forest’ land use groups. The data required for calibration of SIMHYD includes • catchment area • long term (years to decades) daily flow record • spatial coverage of daily rainfall • spatial coverage of daily potential evapotranspiration Long-term Flow records were available for (Bartley et al., 2004) • Daintree@Bairds • Mossman@Mossman • Whyanbeel@ upstream of Little Falls Creek • Saltwater Creek@ Donoghue All these sub catchments were located in areas of natural forest, in upland terrain where rainfall is thought to be highly spatially variable. No data was available for calibration of SIMHYD in the ‘non forest’ land use group. Daily rainfall surfaces were obtained from the Queensland Government, Natural Resources, Mines and Water (QNRMW). These surfaces were interpolated using local records, which included only six sites within the Douglas catchment, principally on the coastal plain. Monthly potential evapotranspiration surfaces were obtained from the National Land and Water Audit (http://www.nlwra.gov.au/). At all calibration sites, the area- weighted rainfall totals were insufficient to account for the observed runoff. This mass imbalance was thought to be consistent with a poor spatial representation of rainfall within these sub catchments and rainfall was therefore scaled upwards to address this. To achieve a reasonable calibration for Whyanbeel upstream of Little Falls Creek (Figure B.2), rainfall was scaled as shown in Table B.1. Table B.1 Rainfall scaling factors applied to calibrate SIMHYD rainfall run off model for the ‘forest’ land use group, within Region 1 (see Figure A.6) Month Jan Feb Mar Apr May Jun Jul Aug Sept Oct Nov Dec

Scaling 1.8 1.5 1.3 1.2 1.0 1.0 1.0 1.0 1.2 1.3 1.5 1.8 factor

This scheme also produced a reasonable calibration for Daintree@Bairds (Figure B.3), for which the contributing area was Daintree National Park sub catchment, however, calibrations for the Mossman@Mossman (Figure B.4) and Saltwater Creek@Donoghue (Figure B.5) sub catchments were poor. For the latter, there was a significant gap in observed flow for the calibration period. Generally, the quality of the calibrations was severely limited by the available data, particularly rainfall.

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25000

20000 Observed flow Simulated flow

15000

10000 Monthly flow (ML) 5000

0 31/1/1993 15/6/1994 28/10/1995 11/3/1997 24/7/1998 6/12/1999 19/4/2001 1/9/2002 14/1/2004 28/5/2005 Date

Figure B.2 Monthly observed flow and monthly flow simulated by SIMHYD for Whyanbeel@ upstream of Little Falls Creek.

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1000000 900000 Observed flow 800000 Simulated flow 700000

600000 500000 400000

300000 Monthly flow (ML) 200000 100000 0 Jan-93 Jun-94 Oct-95 Mar-97 Jul-98 Dec-99 Apr-01 Sep-02 Jan-04 May-05 Date

Figure B.3 Monthly observed flow and monthly flow simulated by SIMHYD for Daintree@Bairds.

180000

160000

140000 Observed flow 120000 Simulated flow

100000

80000

60000 Monthly flow (ML) Monthly 40000

20000

0 Jan-93 Jun-94 Oct-95 Mar-97 Jul-98 Dec-99 Apr-01 Sep-02 Jan-04 May-05 Date Figure B.4 Monthly observed flow and monthly flow simulated by SIMHYD for Mossman@Mossman.

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40000

35000

30000 Observed flow Simulated flow 25000

20000

15000

Monthly flow (ML) 10000

5000

0 31/1/1993 15/6/1994 28/10/1995 11/3/1997 24/7/1998 6/12/1999 19/4/2001 1/9/2002 14/1/2004 28/5/2005 Date

Figure B.5 Monthly observed flow and monthly flow simulated by SIMHYD for Saltwater Creek@Donoghue. Within EMSS, therefore, two hydrologic regions were identified (Figure B.6), broadly divided between the uplands (Region 1; almost entirely forest land use group) and the coastal plains (Region 2; comprising some ‘forest’ and all ‘non forest’ land use group). Within Region 1, the DNRW rainfall surface was scaled as indicated in Table B.1; within Region 2, the DNRW rainfall was used unscaled. The sub catchments contained within these two regions are listed in Table B.2.

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Figure B.6 A map of the Douglas Shire catchments showing hydrologic Region 1 (white) and Region 2 (blue) used in EMSS and boundaries of the 15 sub catchments. Table B.2 Sub catchments within the two hydrologic regions within the Douglas Shire, relating to the rainfall scaling (Table A.1) calibration and the SIMHYD parameters for ‘forest’ and ‘non forest land use groups (Table A.3). Hydrologic regions used in EMSS

Region 1 Region 2

Daintree National Park Daintree estuarine

Daintree developed Daintree South Arm

Stewarts Creek Saltwater Creek developed

Saltwater National Park Saltwater Creek estuarine

Mossman National Park Mossman developed

Mossman estuarine

Mowbray developed

Mowbray National Park

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Mowbray estuarine

Coastal Strip

Table B.3 shows the SIMHYD parameters listed by hydrologic region and land use group as applied within EMSS to describe runoff within the Douglas Shire. We note that this is a very simplistic description of the Douglas Shire hydrology but represents the best possible representation within the limits of data available at the time of this study. Table B.3 The SIMHYD parameters applied within the 2 hydrologic regions used within the EMSS model. Region Group INSC COEFF SQ SMSC SUB CRAK RK 1 Forest 3.3 364 0.8 52 0.535 0.64 0.009 1 Non forest 2 200 1.5 200 0.35 0.7 0.3 2 Forest 5 200 1.5 273 0.35 0.7 0.3 2 Non forest 2 200 1.5 200 0.35 0.7 0.3

B.3 – Pollutant parameters used in EMSS and SedNet EMSS requires specification regarding the event mean concentration (EMC) and dry weather concentration (DWC) for each pollutant, for each land use, and total annual loads of each pollutant from each point source in the catchment. The values used in the Douglas Shire implementation of EMSS are listed in Table B.4. Values for ‘Conservation areas’ and ‘Native bush’ were calculated from data collected from the Mossman National Park sub catchment (see McJannet et al., 2005; Appendix E, Upper Mossman); values for ‘Grazing’, ‘Broadacre agriculture and ‘Intensive agriculture’ were derived from the Wivenhoe (central Brisbane) catchment (Tony Weber, unpublished data). The remaining values are derived from Brisbane catchment, as described in Chiew et al. (2002). Table B.4 Event mean concentrations (EMC) and dry weather concentrations (DWC), for each land use category used in the model EMSS, expressed in mgl-1. Land use TSS TSS TN TN TP TP DWC EMC DWC EMC DWC EMC (mgl-1) (mgl-1) (mgl-1) (mgl-1) (mgl-1) (mgl-1) Conservation areas Lower 0.0001 3.92 0.043 0.29 0.003 0.003 Median 2 21.27 0.091 1.144 0.006 0.036 Upper 3.5 92.1 0.285 2.238 0.017 0.089 Managed forest Lower 3 8 0.3 0.4 0.02 0.05 Median 7 20 0.4 0.8 0.03 0.2 Upper 14 90 0.5 2 0.06 0.4 Plantation Lower 3 8 0.3 0.4 0.02 0.05 Median 7 20 0.4 0.8 0.03 0.2 Upper 14 90 0.5 2 0.06 0.4 Native bush Lower 0.0001 3.92 0.043 0.29 0.003 0.003 Median 2 21.27 0.091 1.144 0.006 0.036 Upper 3.5 92.1 0.285 2.238 0.017 0.089 Grazing Lower 5 110 0.5 1.17 0.03 0.128 Median 10 260 0.7 2.08 0.07 0.3 Upper 23 700 0.9 5.98 0.14 0.77 Broadacre agriculture Lower 5 80 0.5 0.9 0.03 0.107 Median 10 300 0.7 1.95 0.07 0.321

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Upper 23 800 0.9 5.2 0.14 0.803 Intensive agriculture Lower 5 1000 0.5 0.9 0.03 0.12 Median 10 1000 0.7 2.1 0.07 0.36 Upper 23 1000 0.9 5.9 0.14 1.1 Rural residential Lower 5 40 0.5 0.9 0.05 0.12 Median 10 140 0.7 1.6 0.11 0.28 Upper 23 380 0.9 4.6 0.28 0.72 Future urban Lower 5 40 0.9 0.9 0.05 0.12 Median 7 140 1.5 1.6 0.11 0.28 Upper 27 380 2.8 4.6 0.28 0.72 Suburban Lower 5 40 0.9 0.9 0.05 0.12 Median 7 140 1.5 1.6 0.11 0.28 Upper 27 380 2.8 4.6 0.28 0.72 Dense urban Lower 5 40 0.9 0.9 0.05 0.12 Median 7 140 1.5 1.6 0.11 0.28 Upper 27 380 2.8 4.6 0.28 0.72 The SedNet simulations used the concentrations of dissolved inorganic nitrogen DIN, dissolved organic nitrogen DON, filtered reactive phosphorus FRP and dissolved organic phosphorus DOP specified in Table B.5. Table B.5: Estimated average concentrations of dissolved inorganic nitrogen DIN, dissolved organic nitrogen DON, filtered reactive phosphorus FRP and dissolved organic phosphorus DOP in runoff from land uses Wet Tropics Regions (after Brodie et al., 2003). Land use DIN (μg/L) DON (μg/L) FRP (μg/L) DOP (μg/L) Rainforest 40 150 10 10 Ungrazed savannah/ woodland 100 100 20 10 Grazing 200 250 50 12 Sugar cane 1100 350 40 30 Horticulture 500 200 30 20 Forestry 150 150 8 8

B.4 – Implementation of Management Actions

Drain erosion management actions in SedNet A drainage map for the sugar cane areas in Saltwater Creek was provided to CSIRO from Mossman Agricultural Services (MAS). This map was a preliminary map of only the major drains in Saltwater Creek, however, it was the only information available for the Shire. The mapping suggested that the drain density for the catchment was 7.8 m/ha. There was no drain erosion data available for the mapped data, so an erosion rate of 9 t/ha/yr was used based on the detailed drain erosion studies presented in Roth et al. (2003)66. These data were then used to determine an average cross-section area for the drains, and the relationship between drainage density, drain cross-section area, upstream catchment area and sediment bulk density was used to determine the relative contribution coming from drains in those catchments covered by sugar cane. It was highlighted in Bartley et al., (2004) that this approach was preliminary, and more data on both the drainage density, spatial location of different types of drains and erosion rates were required. During 2004/05 staff from MAS have done some more investigation on the drains in Saltwater Creek and have found that there are ~ 56 m of major drains and ~100 m of minor drains per hectare of sugar cane (pers. comm. Daryl Parker). This total length of drain network

66 http://www.clw.csiro.au/publications/technical2003/tr52-03.pdf

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(156 m/ha) is considerably higher than the original density of 7.8 m/ha used in Bartley et al., (2004). However, more information is still required to help improve the modelled estimates and subsequent scenario runs related to drain erosion including: • Digital mapping of drain location for all sugar areas in Douglas Shire, not just Saltwater Creek; • The drains need to be classified into ‘major’, ‘minor’ and ‘swale or spoon’ drain types; • Erosion rates associated with each of the drain types need to be measured or estimated; • Estimates of deposition occurring in the different drain types are also important. Much of the work described above was conducted in the lower Herbert floodplain and the methods used are documented in Visser (2003) and Roth et al. (2003). Without this information it is almost impossible to attribute a reduced drain erosion rate to the different drain types as we simply don’t have this information. It is also considered inappropriate at this stage to revise the drainage density data (from 7.8 m/ha to 156 m/ha) as this will have large implications on the sediment budget for the entire Douglas Shire area, which will also affect the results of the scenario analysis.

Riparian management actions– EMSS For flow and pollutant load calculations within EMSS, the Douglas Shire was divided into 206 ‘small’ sub catchments (note: these were grouped to form the 15 ‘reporting’ sub catchments in the Plan). All land use and management changes within EMSS need to be implemented at this level. To determine the relative response of small sub catchments to riparian treatment, full riparian treatment was first applied to all streams bordering agricultural land. Small sub catchments were identified for final riparian treatment by: 1. determining the pollutant load reduction D from the riparian treatment, compared to current conditions, for each small sub catchment; 2. accumulating D in descending order of magnitude until ∑D = β%. where β% = 50% or 95%, depending on the treatment.

Minimum tillage/legume rotation management actions - SedNet The hillslope sediment generation procedure used by SedNet (Prosser et al., 2001) is based on the Revised Universal Soil Loss Equation RUSLE (Renard et al., 1997), which describes the protection afforded to exposed soil by vegetation/residue using a ‘cover’ factor, C. For the minimum tillage/legume rotation management action, the cover factor C for sugar cane land use was adjusted as follows: ⎡ ⎤ Arotation C newsugar )( ⎢Csugar ×−= Csugar ⎥ (2 ⎣⎢ Asugar ⎦⎥

Where Arotation is the area representing the minimum tillage/legume rotation, Asugar is the total area of sugar cane, Csugar is 0.056 (see Table B.6).

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Table B.6. C factor and average slope values used in the RUSLE calculations for the Douglas Shire Project. Average slope values for each land use were obtained from the DEM. N/A means ‘not applicable’. Land use C factors used in this study Average hillslope gradient (%) Quarry 0.07 1.14 Fruit trees (e.g. bananas) 0.056 9.94 Sugarcane 0.056 1.71 Cleared 0.025 5.08 Headland 0.017 as for sugarcane Grazing 0.016 9.20 Regrowth 0.015 8.10 Rural Residential 0.015 12.14 Production Forestry 0.012 N/A, area < 1% Dry Sclerophyll 0.01 25.48 Wet Sclerophyll 0.008 25.48 Rainforest 0.006 28.39 Road 0.003 2.82 Tourism areas 0.003 4.62 Urban 0.003 2.86 Industrial 0.003 8.39 Other 0.003 1.14 Aquaculture 0.003 as for ‘other’ Dunes 0.001 as for ‘other’ Coastal Mozaic 0.001 as for ‘other’ Melaleuca/Transitional 0.001 as for ‘other’ Water 0.001 as for ‘other’

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B.5 Results Table B-7. Percentage reduction in total Shire pollutant loads as a result of applying management actions or simulating possible land use changes. The figures in brackets show the percentage change in load within that subcatchment.

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estuarine Pollutant Coastal strip strip Coastal Daintree – estuarine Daintree - developed Daintree - developed Saltwater - estuarine Mowbray - estuarine - estuarine Mowbray Mossman - estuarine - estuarine Mossman Saltwater - developed Saltwater - developed Mossman - developed Mossman - developed Mowbray - developed - developed Mowbray Daintree - South Arm Daintree - South Arm Daintree - Stewart Creek Daintree - Stewart Saltwater - National Park Park - National Saltwater Management Actions Park - National Mowbray TOTAL

7 Year Scenario SUGAR CANE TSS N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A Reduce N losses from sugar cane by 35% through improved TN 1(13) N/A 0(4) N/A 0(14) 1(21) 0(33) 0(2) 0(24) 0(6) 1(12) 0(24) 0 3 management TP N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A TSS 6(24) N/A 0(6) N/A 1(20) 4(25) -1(31) 0(2) 0(35) 0(0) 2(19) 0(24) 0(0) 12 Repair/modify drains by 65% TN 0(3) N/A 0(1) N/A 0(2) 0(3) 0(3) 0(0) 0(8) 0(0) 0(2) 0(3) 0(0) 0 [proportioned to 40% swale, 25% deep drain]. TP 1(3) N/A 0(1) N/A 0(4) 1(7) 0(3) 0(1) 0(22) 0(0) 1(3) 1(9) 0(0) 4 TSS 0(1) N/A 0(0) N/A 0(1) 0(1) 0(0) 0(0) 0(0) 0(15) 0(1) 0(1) 0(0) 0 Introduce 60% legume planting during TN 0(4) N/A 0(0) N/A 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 0 sugar cane fallow period TP 0(0) N/A 0(0) N/A 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 0 GRAZING TSS 0(0) 0(5) 0(2) 0(0) 0(0) 0(0) 0(0) 0(21) 0(0) 0(0) 0(0) 0(0) 0(2) 0 Maintain yearly average cover of (95%) on slopes >8% slope on 100% TN 0(0) 0(0) 0(3) 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 0(3) 0 of grazing land TP 0(0) 2(25) 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 2 TSS N/A 0(5) 0(1) 0(5) 0(0) N/A N/A N/A N/A N/A N/A N/A N/A 0 80% improvement in riparian TN N/A 0(3) 0(0) 0(3) 0(0) N/A N/A N/A N/A N/A N/A N/A N/A 0 vegetation in Daintree grazing area TP N/A 0(4) 0(0) 0(0) 0(0) N/A N/A N/A N/A N/A N/A N/A N/A 0 TSS N/A Z/(L) N/A Z/(L) N/A N/A N/A N/A N/A N/A N/A N/A N/A Z N/A Z/(L) N/A Z/(L) N/A N/A N/A N/A N/A N/A N/A N/A N/A Manage burning practices to minimise TN Z runoff TP N/A Z/(L) N/A Z/(L) N/A N/A N/A N/A N/A N/A N/A N/A N/A Z RIPARIAN TSS N/A N/A N/A N/A N/A 0(1) N/A N/A N/A N/A N/A N/A N/A 0 80% improvement in riparian vegetation in Cassowary sub- TN N/A N/A N/A N/A N/A 0(0) N/A N/A N/A N/A N/A N/A N/A 0 catchment TP N/A N/A N/A N/A N/A 0(0) N/A N/A N/A N/A N/A N/A N/A 0 TSS 0(0) 0(11) 0(0) 0(12) 0(0) N/A 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 147 0 50% improvement of riparian vegetation in other catchments TN 0(0) 0(0) 0(0) 0(1) 0(0) N/A 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 0 TP 0(0) 0(2) 0(0) 0(3) 0(0) N/A 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 0 Draft Water Quality Improvement Plan

POINT SOURCES TSS N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A Reduce export of all pollutants from point sources – sewage and TN 1(15) N/A 0(1) N/A 0(2) 0(3) 0(22) N/A N/A N/A 0(1) 0(2) 0(0) 1 stormwater - by 75% TP 7 (37) N/A 0 (3) N/A 0 (8) 0 (7) 1 (43) N/A N/A N/A 0 (3) 0 (6) 0 (0) 8 HORTICULTURE TSS Z/(L) Z/(L) N/A Z/(L) N/A Z/(L) N/A N/A N/A N/A Z/(L) N/A N/A Z Adoption of Farmcare Code of Z/(L) Z/(L) N/A Z/(L) N/A Z/(L) N/A N/A N/A N/A Z/(L) N/A N/A Practice TN Z TP Z/(L) Z/(L) N/A Z/(L) N/A Z/(L) N/A N/A N/A N/A Z/(L) N/A N/A Z ROAD MANAGEMENT TSS Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z Sealing high impact raods; trapping Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) sediment runoff; maintaining ground TN Z cover on verges TP Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z TSS 25 21 9 17 21 27 31 23 35 15 20 25 2 12 TOTAL reduction in pollutant TN 35 3 9 4 18 27 58 2 32 6 15 29 3 4 loads as percentage of sub- catchment TP 40 31 4 3 12 14 46 1 22 0 6 15 0 14

25-year scenario SUGAR CANE TSS N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A Reduce N losses from sugar cane by 50% through improved TN 1 (19) N/A 1 (6) N/A 0 (21) 1 (31) 0 (50) 0 (2) 0 (36) 0 (9) 1 (18) 1 (35) 0 (1) 5 management TP N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A TSS 8 (35) N/A 1 (8) N/A 1 (28) 6 (35) -3 (47) 0 (3) 1(48) 0 (0) 3 (26) 1 (36) 0 (2) 18 Repair/modify drains by 95% [proportioned to 60% swale, 35% TN 0(3) N/A 0(1) N/A 0(2) 0(4) 0(0) 0(1) 0(12) 0(0) 0(2) 0(5) 0(0) 0 deep drain] TP 1(3) N/A 0(1) N/A 0(5) 1(11) 0(4) 0(1) 0(37) 0(0) 1(5) 1(12) 0(0) 4 TSS 0(1) N/A 0(1) N/A 0(2) 0(1) 0(0) 0(0) 0(0) 0(0) 0(0) 0(2) 0(0) 0 Introduce 100% Legume planting TN 0(4) N/A 0(0) N/A 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 0 during sugar cane fallow period. TP 0(0) N/A 0(0) N/A 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) (0) 0 GRAZING TSS 0(0) 0(5) 0(2) N/A 0(0) 0(0) 0(0) 0(21) 0(0) 0(0) 0(0) 0(0) 0(2) 0 Maintain yearly average cover of TN 0(0) 0(0) 0(3) N/A 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 0(3) 0

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(95%) on slopes >8% slope on 100% of grazing land TP 0(0) 2(25) 0(0) N/A 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 2 TSS N/A 0(5) 0(1) 0(5) 0(0) N/A N/A N/A N/A N/A N/A N/A N/A 0 80% improvement in riparian TN N/A 0(3) 0(0) 0(3) 0(0) N/A N/A N/A N/A N/A N/A N/A N/A 0 vegetation in Daintree grazing area TP N/A 0(4) 0(0) 0(0) 0(0) N/A N/A N/A N/A N/A N/A N/A N/A 0 TSS N/A Z/(L) N/A Z/(L) N/A N/A N/A N/A N/A N/A N/A N/A N/A Z N/A Z/(L) N/A Z/(L) N/A N/A N/A N/A N/A N/A N/A N/A N/A Manage Burning practices to TN Z minimise runoff TP N/A Z/(L) N/A Z/(L) N/A N/A N/A N/A N/A N/A N/A N/A N/A Z TSS N/A N/A N/A N/A N/A 2(13) N/A N/A N/A N/A N/A N/A N/A 2 95% improvement of riparian vegetation in Cassowary (Mossman) TN N/A N/A N/A N/A N/A 0(6) N/A N/A N/A N/A N/A N/A N/A 0 sub catchment TP N/A N/A N/A N/A N/A 3(50) N/A N/A N/A N/A N/A N/A N/A 3 TSS 0(0) 0(22) 0(3) 0(23) 0(1) N/A 0(6) 0(2) 0(3) 0(0) 0(2) 0(4) 0(0) 1

95% improvement of riparian TN 0(0) 0(1) 0(0) 0(1) 0(0) N/A 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 0 vegetation in all other catchments TP 0(0) 0(4) 0(0) 0(5) 0(0) N/A 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 0(0) 0 TSS N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 12 - Reduce export of all pollutants from point sources by 75% TN 1(15) N/A 0(1) N/A 0(2) 0(3) 0(22) N/A N/A N/A 0(1) 0(2) 0(0) 1 TP 7 (37) N/A 0 (3) N/A 0 (8) 0 (7) 1 (43) N/A N/A N/A 0 (3) 0 (6) 0 (0) 8 HORTICULTURE TSS Z/(L) Z/(L) N/A Z/(L) N/A Z/(L) N/A N/A N/A N/A Z/(L) N/A N/A Z Adoption of Farmcare Code of Z/(L) Z/(L) N/A Z/(L) N/A Z/(L) N/A N/A N/A N/A Z/(L) N/A N/A Practice TN Z TP Z/(L) Z/(L) N/A Z/(L) N/A Z/(L) N/A N/A N/A N/A Z/(L) N/A N/A Z ROAD MANAGEMENT TSS Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z Sealing high impact roads; trapping Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) sediment runoff; maintaining ground TN Z cover on verges TP Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z/(L) Z TOTAL reduction in pollutant TSS 36 32 15 28 31 49 53 26 51 0 28 42 4 21 loads as percentage of sub- TN 26 4 11 4 25 44 72 3 48 9 21 42 3 6

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catchment TP 40 33 4 5 13 68 47 1 37 0 8 18 3

Sources: 1. Diffuse source changes from CSIRO modelling67 with changes to management actions 1, 2, 4, 5, 7, 13, 14, 16, 17 because of subsequent corrections. 2. Pollutant reductions calculated using field survey data for riparian management (Management Actions 7, 17) for “Daintree – developed” and Daintree – Stewart Creek”. Other sub-catchments use CSIRO modelling results. 3. The effect of repairing drains in the “Mossman – estuarine” river reach on TSS loads is negative because net sediment deposition occurs in this river reach and its floodplain. Point source changes from Douglas Shire Council data and QEPA. 4. Data were not available to estimate the effects of improved management of Horticulture, Roads and burning practices on grazing land. These management actions were given a qualitative rating of Zero (Z), Low (L) and were not included in the totals.

67 T. Ellis, R. Bartley, J. Rahman, T. Webster, A. Henderson, C. Magee, J.Austin, P. Hairsine, S. Davies, S. Cuddy, and J. Macmullin. (2005). Application of two water quality models as a decision support system within the Douglas Shire. A report to the Douglas Shire Council and the Department of Environment and Heritage. CSIO Land and Water April 2005.

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Appendix C. Milestone activities undertaken in projects supporting the DSWQIP process (Activity reports can be viewed at www.dsc.qld.gov.au/)

Project 1: Adoption of Agricultural Best Management Practice for Sediment and Nutrient Reduction in Douglas Shire MILESTONE ACTIVITY 1 Identify critical sources of sediment & nutrient in Douglas Shire waters (desktop study) – excluding Saltwater Creek 2 Determine BMP's for all agricultural activities within Douglas Shire: Grazing, Cane, Horticulture, etc. 3 Develop BMP self-assessment procedure 4 Devise independent audit procedure for BMP assessment 5 Develop BMP implementation strategy, including process for evaluating BMP cost-effectiveness 6 Determine BMP incentives 7 Prioritise landholders/areas for BMP adoption (excluding Saltwater Creek) 8 Initial consultations with top priority landholders 9 Commence upgrading of DSC native plant propagation facilities 10 SedNet modelling of sediment & nutrient sources - excluding Saltwater Creek 11 Critical source scenario analysis with landholders, interpretation for BMP and integration into DSS - excluding Saltwater Creek 12 Implement BMP monitoring program; including preliminary report on BMP cost-effectiveness 13 Landholder consultations and agreements 14 Propagation of locally native plants 15 Incorporation of results of Projects 2, 3 & 5 to update critical source information 16 Revise BMP's in light of info from Projects 2 and 5 17 Implement BMP monitoring program; including final report on BMP cost-effectiveness 18 Final agreements with landholders re adoption of BMP's - 30% 19 Certification/accreditation alternatives explored 20 Program for further adoption of BMP's 21 Regulations examined and in place to minimise export of sediment and nutrient 22 Propagation of locally native plants

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Executive Summary

The project’s objective is to maximise the adoption rate of the Best Management Practices (BMPs) that improves water quality by reducing sediments and nutrients leaving farms in the Douglas Shire, Far North Queensland. A stepwise progression approach was used, which was a to; ƒ Identify the critical sources ƒ Determine BMPs that impact on water quality ƒ Develop a BMP monitoring program that includes an Implementation Strategy and the cost-effectiveness of key BMPs ƒ Sought landholder agreements to commit to key BMPs ƒ Develop a program for further BMP that extends beyond the life of this project ƒ Identify the control mechanisms available as a “last resort approach”

Another component was to upgrade the Douglas Shire Council’s native plant nursery and providing resources for increased production of plants for use in Interim Project’s 1, 2 & 4 of the DS Water Quality Improvement Plan.

Critical source identification highlighted that within the diffuse industry sector drain management, fertliser management and riparian zone management were key areas where improvement could be made in reducing pollutant loads. While the estimated load figures produce by SedNet modelling have been revised with the incorporation of an Environmental Management Support System, local data and observation support the direction of resources to areas highlighted from modelling. Minimum tillage is also included as a key area. With minimum tillage there need to be a grouping of BMPs that are essential when applying a whole farm systems approach to managing an enterprise.

A whole suite of BMPs was correlated concurrently with critical source identification. Key BMPs that addresses the key sources were chosen for implementation. To maximise adoption the project clearly identifies that the drivers are the landholders themselves and that industry led extension services are the appropriate bodies to deliver. Within this shire the sugar industry have local infrastructure to deliver extension services while the grazing industry, which is the second largest, in area, lacks this local service. This has meant that within this project the sugar industry is further advanced in tackling higher adoption rates of BMPs compared to grazing.

Where adoption of a BMP provides a positive economic return to their enterprise then, with extension, the willingness is there, eg, reducing Nitrogen losses by reducing application. An action that gives a negative economic return requires both extension and an appropriate level of public investment, eg, riparian zone management.

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This project has provided public investment into drain management, legume fallows, identifying mechanisms to reduce Nitrogen losses and off- stream watering points. Interim Project 4 provided public investment to riparian and wetland restoration. The monitoring component is a continuous improvement process that looks at evaluating the extension program as well as changes in practices. Changes in practices is monitored by a self-assessment process by landholders where they have identified their present practices and work with their extension service provider in developing a series of activities for implementing BMP. This is well advanced in the sugar industry compared to grazing.

The consultation undertaken in this project make it clear that appropriate extension is essential, and with certain practices, adequate cost- sharing arrangements are in place when community expectation to reduce pollutant loads entering the Great Barrier Reef lagoon are high.

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Project 2: Determination and Demonstration of Agricultural BMP in the Saltwater Creek Catchment of Douglas Shire MILESTONE ACTIVITY 1 Identify critical sources of sediment and nutrient in Saltwater Creek - desktop study 2 Evaluate COMPASS and Code for application to BMP 3 Consultations with landholders on BMP and develop draft local BMP's for relevant industries 4 SedNet modelling of sediment and nutrient sources for Saltwater Creek (high resolution) 5 Critical source scenario analysis with landholders, interpretation for BMP and integration into DSS for Saltwater Creek 6 Landuse change facilitated 7 Incorporate critical source findings/modelling into revised BMPs & define process for further refinement 8 Commence to establish landholder agreements within Saltwater Creek 9 Refine ID of critical sources of sediment and nutrient with results form Project 5 10 Landholder agreements finalised with 50% landholders in sub-catchment 11 Landuse change facilitated 12 Evaluate BMP uptake (survey and audit) 13 Evaluate BMP effectiveness (uptake rate, SedNet modelling), including application of benefits framework to the sub-catchment 14 Feed any further adjustments into BMPs

Executive Summary This project is part of the Douglas Shire Water Quality Improvement Program, which was implemented in Douglas Shire to develop a Water Quality Improvement Plan. The Water Quality Improvement Plan describes water quality objectives desired by a community and management actions to be implemented to achieve those objectives. This project identified those management actions for agricultural land uses and determined their effectiveness in controlling diffuse sources of sediment and nutrient. The Saltwater Creek catchment was chosen for extensive BMP implementation because of its small size with a high proportion of agricultural land devoted to sugarcane (>91%). The specific objectives of this project are to: Establish best management practice for agricultural activities within the Saltwater Creek catchment; Identify critical sources of sediment and nutrient for the catchment, using existing information and modelling; Facilitate support for land-use change by Queensland EPA; Develop agreements with catchment landholders to implement BMPs for sediment and nutrient control;

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Evaluate BMP uptake and effectiveness in reducing nutrient and sediment loads to the GBR.

This project identified BMPs as those management actions presently known to be the best for abating water quality decline in the Douglas Shire. Draft BMPs were determined from codes of practice and local knowledge. Because of the agricultural focus on sugarcane in Saltwater Creek, there was a major focus in this project on BMPs for sugarcane production. Critical sediment and nutrient source identification in Saltwater Creek along with an analysis of cost effectiveness of management actions was used to refine BMPs specific to catchment in the present time. The nature of farming as a complex and dynamic system leads to BMPs that should be implemented in a systems approach. Singular BMPs are not implemented in isolation, but as part of a new farming system incorporating a number of BMPs.

Identification of critical sources of nutrients in the catchment was achieved through a modelling approach (SedNet and ANNEX). Loads of sediments, nitrogen and phosphorous (organic and inorganic) were calculated for identified internal catchments and, once deposition was accounted for, aggregated to determine end of catchment loads.

Modelling showed sediment originating from drain erosion and hillslope erosion from the forested sections of the catchment being the major sources of sediment. Management practices addressing drain erosion would bring about the most benefits in abating sediment erosion. Nitrogen exports are modelled as being highest from sugarcane production areas. With the dominance of sugarcane in Saltwater Creek, and the intensive use of soluble fertiliser in sugarcane production, the largest gains in controlling nitrogen runoff will arise from application of BMPs for nutrient management.

The Queensland EPA supported land management practice change in sugarcane production through provision of funds to landholders to facilitate change. This funding over two rounds attracted eleven growers to implement BMPs for riparian and wetland repair, fertiliser management and drains improvement.

The identified BMPs for nutrient and sediment abatement became subject to the project providing growers incentives for implementation on farm where the cost effectiveness analysis of implementing the BMP indicate growers would be financially worse off to implement. In Saltwater Creek grower were offered incentives to implement a BMP farming system incorporating controlled traffic, reduced (strategic) tillage and legume fallows, and incentives to rehabilitate and repair drains.

Due to the time frame over which the project took place it is not possible to get an accurate picture of BMP uptake. To assess potential uptake an attitude survey was undertaken to assess growers attitude BMPs and likelihood of them implementing BMPs. Results indicate growers are

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willing to implement BMPs where there has been a demonstrated economic benefit to implementation. Growers are not willing to implement BMPs where the economic cost of implementation is not recovered through the management action. In these cases growers indicated financial incentives would encourage them to implement the BMPs.

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Project 3: Control of Point Source Discharges of Sediment & Nutrient in Douglas Shire MILESTONE ACTIVITY 1 Commence work on establishment of monitoring strategy for point source discharges 2 Integrate BMPs with existing & potential bylaws and regulations 3 Prepare uptake schedule 4 Monitor uptake rate of BMPs 5 MoU on point source discharge control with QEPA 6 MoU with NR&M on changes to flow regimes and data sharing 7 Finalise monitoring strategy, including a monitoring program, for point source discharges 8 Monitor uptake rate of BMPs 9 Implement 1st year priorities in pt. source discharge upgrade program 10 Establish phased enforcement program to ensure point source discharges are within set limits

Conclusion

Within the first phase of this project it was determined that point sources contribute 0.7% of Total Nitrogen and 9% of Total Phosphorus of the total pollutant loads entering the Great Barrier Reef lagoon. The present management of effluent, both licensed and unlicensed, was considered the greater contributor to point source loads. A program of upgrades of existing Sewage Treatment Plants (STP), plus the installation of STPs to replace septic systems has been outlined in previous reports covering this project – refer to www.dsc.qld.gov.au that provide greater detail. The expected completion is in the order of 5 – 7 years. Once completed the reduction of TP will be significant, especially in the Mossman Catchment that has the higher level of pollutant loads derived from point sources.

While the effluent upgrades will reduce loads from townships, there will be the issue of overland flow and seepage from septic systems in the rural residential zones. However, the overall contribution from this source, based on modelling is considered minimal.

Other licensed point sources while meeting their scheduled conditions can further improve their management practices in respect to improving the discharge quality. For this to occur the Queensland Environmental Protection Agency and the organisations generating discharge need to continue their dialogue to identify the mechanisms to improve management practices.

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Unlicensed point sources, specifically development/building sites and quarries have been contacted with site visits from Douglas Shire Council staff that have undertaken accredited erosion control training and who are delegated to enforce the Environmental Protection (Water) Policy, 1997 (EPP). These initial visits were designed to provide developers and contractors appropriate information to minimise pollutants leaving sites and to highlight obligations to comply with the EPP. Currently, DSC staff is inspecting quarry sites for compliance to the Environmental Management Plan submitted to Council before renewal permits were issued.

The tourism industry in this shire has marketed the area for the quality of landscape and the pristine reefs. The tourism client base is becoming more concerning for providers to operate eco-efficient services. Tour operators, if utilising either World Heritage areas such as the Daintree National Park or the Great Barrier Reef require accreditation by the managers of those sites. Accreditation accounts for the provision of an eco-efficient service. In determining the level of adoption of Best Management Practices (BMPs) within other sectors of the tourism industry a survey conducted within this project indicates that a high level of commitment exists with accommodation houses and restaurants. As a framework, BMPs are dynamic and there is a requirement by organisations such as DSC and QEPA to supply a service that continually seeks improvement. The DSC has provided a commitment that seeks Greenglobe accreditation and the QEPA – Sustainable Industries will provide their services to seek a high attainment of BMPs within the tourism sector.

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Project 4: Protection and Restoration of Riparian and Wetland Areas in Douglas Shire MILESTONE ACTIVITY 1 Collate existing information of degradation of riparian and wetland areas 2 Survey of riparian & wetland areas to complete degradation information 3 Ranking priorities for restoration work 4 Develop remediation plan based on priorities 5 Develop incentives scheme for riparian & wetland protection 6 Initial talks with landholders on caveats on titles 7 Negotiations with at least 6 landholders commenced 8 Identify best bets for remediation work, based on caveats being placed on titles, and prioritise 9 Negotiations with landholders continuing 10 Titles signed with 3 landholders (minimum) 11 Establish works schedule 12 Titles signed with total of at least 6 landholders (except concentration in Saltwater Creek) 13 Restoration works implemented (using plant propagues from project 1) on land of at least 6 landholders

Summary The principal objectives of this project were to:

ƒ Provide a detailed list of sites where remediation measures will reduce sediment and nutrients from entering the Great Barrier Reef Lagoon. ƒ Undertake consultation with landholders to agree on a remediation work’s program. ƒ Input relevant detail into the Douglas Shire Water Quality Improvement Plan.

Based on both desktop and field studies a remediation plan was developed that highlighted priority areas for remedial actions. From this process 35 priority sites were identified and graded from low to high priority. Of these sites, several sub-catchments were highlighted as requiring further detailed investigation.

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68A completed detailed survey in the Upper Whyanbeel Creek (Saltwater Catchment) describes priority riparian restoration works (Smith, T, 2004). At the time of this report production, further agreements with landholders and initial consultation with landholders are occurring. The total cost of works has been identified as approximately $199,000. A schedule will need to be developed with the landholders for onground activities that have not been committed to this project.

69A second detailed study has been completed in the Daintree Catchment that is investigated Stewart, Douglas sub-catchments and a reach of the Daintree River between Creb Crossing, (316500; 8210200) and Daintree Village. In an earlier survey undertaken by Werren, (2004b) much of the area was deemed high priority. A further refinement of this survey compared to the Upper Whyanbeel will be to attribute the causal effects. In undertaking this survey, it is the intention to design and format the process as to be able to incorporate into other catchments/regions.

In the early stages of the project priority areas were not identified due to the time scheduling of the activities in the project and further data requirements from the other projects, therefore the Douglas Shire Council staff utilised the following criteria to seek agreements from landholders:

ƒ landholders interested to undertake works ƒ that work undertaken would provide a benefit of reduced loads entering the Great Barrier Reef Lagoon.

From the consultation with DSC staff and landholders 19 Voluntary Management Agreements have been signed between the landholders and Douglas Shire Council. There are a further 4 sites where work is required, but are awaiting Department of Natural Resources, Mines and Water, Riverine Protection Permit.

From the 9 parcels of land where works have been undertaken a total of approximately 15,000 seedlings have been planted and 2 wetlands constructed. A further 16,000 seedlings and 6 wetlands to be constructed over the next planting season and when machinery is able to access sites for wetland development.

68 To update outcomes of this survey, work has commenced on reach 4 - high priority site that involves redeveloping the eroded meander line with use of cross-dozing, releasing pressure point obstacles and revegetation. Materials for alignment fencing has been ordered and initial consultation for the formation of a community group to undertake responsibility of implementing the action plan (Smith, T, 2004) 69 At the time of writing, field survey work has been completed and will be available early in December 2004.

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There will be sites that although requiring urgent attention, will not have landholder support. This lack of support is generally attributed to either some or all of the following:

ƒ the landholder not identifying the situation as an issue ƒ lack of resources by the landholder ƒ attributing the cause of the issue as being upstream

Therefore, a consultative program must be in place to maintain a sound dialogue with landholders resistant for work to be undertaken. This process needs to work in conjunction with seeking resources to undertake further work programs on identified sites where the landholder is willing.

Appendix One highlights the areas identified in Werren’s report and the criteria used in that report.

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Project 5: Monitoring & Modelling of Sediment & Nutrient Flow Within & From Waters of Douglas Shire MILESTONE ACTIVITY 1 Purchase, assembly and testing of 8 fully automatic monitoring stations 2 Installation of 8 fully automatic monitoring stations 3 Community water quality coordinator hired; network initiated 4 1st iteration of DSC Monitoring Strategy 5 LEMSS decision support system initiated 6 Community WQ network operating, and collecting samples 7 QA/QC program for community monitoring 8 Samples analysed 9 Design of desktop system for delivery & integration of monitoring data 10 DSS finalised 11 DSC Monitoring Strategy revised 12 Desktop system for delivery & integration of monitoring information evaluated 13 Community monitoring on-going 14 All relevant sample analysis completed 15 DSS evaluated and revised Incorporation of project results, including monitoring data, monitoring strategy, and DSS into Shire planning, works, development and assessments 16 etc., through statutory and non-statutory planning provisions

Executive Summary

One of 5 interim projects to assist in the development of the Douglas Shire Water Quality Improvement Plan, Far North Queensland, this project had the objectives to (a) determine suspended solids, Nitrogen and Phosphorus loads moving through the landscape; (b) build the capacity of the community in water monitoring; and, (c) to utilise modelling in predicting load outputs from various management scenarios. The monitoring and modelling coverage was within 4 catchments, totalling approximately 1,860 sq km.

Water monitoring encompassed monthly ambient sampling undertaken by community volunteers for 18 months and event based sampling utilising automatic sampling stations during the 2003/2004 and 2004/2005 wet seasons.

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Ambient sampling was undertaken at 12 sites within the 4 catchments and captured several landuses. Results indicate that as a general rule stream concentration levels of Nitrogen and Phosphorus, and turbidity complied to the draft Douglas Shire Water Quality Objectives given to the aquatic ecosystem Environmental Value. Although Cassowary Creek, Mossman Catchment exceeded the objectives continually.

Results from water monitoring within a predominantly grazing subcatchment increases in concentration between where grazing commences and at the end of the subcatchment, especially TSS and turbidity. A “sugar subcatchment” also increases in concentrations of TSS, TN, TP and turbidity, with nutrients having a greater increase.

Event sampling for 5 of the 7 automatic stations was designed to sample in-stream at sites leaving protected “forested” areas and at end of catchment. The remaining 2 stations were installed, as well as lysometers, on-farm to collect concentration data in a N-loss trial. Only 2003/2004 samples were analysed and interpreted.

Interpreting in-stream monitoring results indicates that concentrations of nutrients and sediments peak early in the wet season, although the proportion of total loads moved is still greater during the later part of the wet season when prolonged monsoonal events and tropical depressions results in high discharges.

The concentration data from the two Mossman River stations (upper and lower positions in the catchment) indicate that there is a source of phosphorus between the two stations. The mean total nitrogen and organic nitrogen concentrations decrease between the two stations as a result of dilution but the concentration of dissolved forms increases. These findings are consistent with nutrients entering the river from the agricultural region on the coastal floodplain. The data also indicate that the agricultural lands of the coastal floodplains and tributary streams are a sediment source.

Loads were determined, based on the 2003/2004 wet season for the Upper Mossman and Upper Daintree sites. Annual estimations were; Upper Mossman – 2902 tonnes of TSS (334kg/ha); 151 tonnes of TN (17.4kg/ha); and 4.48 tonnes of TP (0.52kg/ha), Upper Daintree – 225,200 tonnes of TSS (2,478kg/ha); 3,581 tonnes of TN (39.4kg/ha); and 241 tonnes of TP (2.65kg/ha). Uncertainty exist between differences in delivery rate (kg/ha/yr) of the Mossman “forested area” and Daintree “forested area. The various forest associations could give some indications as to why.

The on-farm N-loss trial results indicate significant loads of nitrogen, mainly as NOX, were lost via sub-surface pathways. There were higher sub-surface nitrogen loads from the higher application rate plots. Subsurface phosphorus loads were very low. Overall, there was 44% more nitrogen being lost to water (both surface and sub-surface) from the higher fertilization rate (190kg N/ha c.f. 98kg N/ha). Therefore, as long as

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the plant is receiving sufficient nitrogen for growth, it appears that a higher application rate is too high, which results in higher environmental losses of nitrogen for a very small financial gain.

A Decision Support System was developed for these 4 catchments. Two models were incorporated into the Decision Support System; EMSS is a distributed parameter, daily time step model, which was calibrated to local conditions (measured pollutant concentrations and stream flow); SedNet is a non-calibrated, process-based annual average model based on the Revised Universal Soil Loss Equation RUSLE

When comparing monitoring and modelling estimations there exist significant variations. With modelling the absolute values are considered unreliable. However, the running of management actions did provide relative guidance to input into Projects 1 and 2.

To further refine load estimations there is recommendations to (a) undertake further monitoring – upto 5 years and (b) determine flow rates at the lower, “end-of-catchment” automatic stations. The Decision Support System can also be refined with the input of monitoring data from the stations, plus other local information such as groundcover indices related to wet tropics.

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Appendix D. Relationship of WQIP Management Actions to FNQ NRM Ltd Management Actions and expanded table of actions relating to Table 4.6

Table AD- 1: Linkage of management actions to FNQ NRM Ltd management action targets AREAS THAT THE WQIP HAS FNQ NRM LTD FNQ NRM LTD IDENTIFIED FOR ACTION MANAGEMENT ACTION TARGETS1 LINK TARGETS1 POINT SOURCE - Upgrades 2W3.5 (3.5.2) – Sewage plants all meet tertiary standards by 2010. B2, B5, B7, B8, B9, B16, B18, B19,W1,W2 SUGAR CANE – Nutrient Management W3.7 (3.7.1 to 12) – In co-operation with industry, increase the adoption of B1, B3, B4, B5, B7, B8, B9, B19, management practices that promote water quality improvements from 2004. CB1, L3, L4, L7, L8, ME1, W1, W2, W3 2L1.6 (1.6.1 to 10) – Sugar cane industry refine extension programs to improve B1, B3, B6-9, CB1, L3, L4, L7, land and water management practices by 2008, in addition to specific audited L8, W1-3 adoption targets. SUGAR CANE – Fallow Management W3.7 (3.7.1 to 12) – In co-operation with industry, increase the adoption of B2,B3, B7, B8, B9, B15-17, B19, management practices that promote water quality improvements from 2004. B21, CB1, L1, L3, L7, L8, ME1, W4, W5 SUGAR CANE – Shallow Drain W3.7 (3.7.1 to 12) – In co-operation with industry, increase the adoption of B1, B3, B8, CB1, L2, W3, W6, L4, Management management practices that promote water quality improvements from 2004. L7, L8 L1.1 (1.1.1, 2, 4, 5, 6) – Collate & calibrate targets for soil loss rates for B1, B3, B8, CB1, L2, W3, W6, L4, different erosion & sediment management strategies by 2005. L7, L8 SUGAR CANE – Deep Drain Management W3.7 (3.7.1 to 12) – In co-operation with industry, increase the adoption of B1, B3, B8, CB1, L2, W3, W6, L4, management practices that promote water quality improvements from 2004. L7, L8 L1.1 (1.1.1, 2, 4, 5, 6) – Collate & calibrate targets for soil loss rates for B1, B3, B8, CB1, L2, W3, W6, L4, different erosion & sediment management strategies by 2005. L7, L8 GRAZING W3.7 (3.7.1 to 12) – In co-operation with industry, increase the adoption of W3.7, L1.4, B7.2, B8.1, B8.2, management practices that promote water quality improvements from 2004. B8.3, B9.1, B9.4, B11.1 L1.2 (1.2.3, 4, 5) – Land managers adopt BMPs by 2010 in each major industry B1, B3, B8, CB1, L2, W3, W6, L4, in the Wet Tropics. L7, L8 WETLANDS W3.8 (3.8.2) – Enhance priority riparian areas & wetlands from 2004 B2, B3, B7-9, B15-17, B19, B21, 2B7.1 (7.1.1 to 7.1.4) – Protect and manage for conservation all wetlands CB1, L1, L3, L7, L8, ME1, W4, mapped as having National & State significance, by 2010 W5 B7.2 (7.2.1 to 7.2.5) – Protect and manage for conservation purposes additional B3, B18, B19, L1, W1, W3, W4 wetlands of regional significance by 2008 B3, B18, B19, L1, W1, W3, W4

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B9.1 (9.1.1 to 9.1.3) Increase understanding of the physical & biological B7-9, B16-20, L1, L7, W1, W3, requirements of inland aquatic ecosystems by 2010 W4 ROADS W3.7 (3.7.1 to 12) – In co-operation with industry, increase the adoption of B1, B3, B8, CB1, L2, W3, W6, L4, management practices that promote water quality improvements from 2004. L7, L8 MARINE W3.6 (3.6.1) – prepare targets for timing the introduction of sewage pump out at B2, B5, B7, B8, B9, B16, B18, marinas. B19,W1, W2, B13.1 ALL COMPONENTS TO IMPLEMENT W3.7 (3.7.1 to 12) – In co-operation with industry, increase the adoption of B1, B3, B8, CB1, L2, W3, W6, L4, THE WQIP - Monitor for change in management practices that promote water quality improvements from 2004. L7, L8 practices, loads, instream & data capture L1.1 (1.1.1, 2, 4, 5, 6) – Collate & calibrate targets for soil loss rates for B1, B3, B8, CB1, L2, W3, W6, L4, of “gaps” different erosion & sediment management strategies by 2005. L7, L8 B9.1 (9.1.1, 2, 3) – Increase understanding of the physical and biological B7-9, B16-20, L1, L7, W1, W3, requirements of inland aquatic ecosystems by 2010. W4 B9.4 (9.4.1) – establish benchmarks and water quality monitoring programs by B10, B12, B14, W1, W3, L1 2005. B9.5 (9.5.1, 2, 3) – Increase community involvement in monitoring and B7-9, B16-19, L1, L7, ME1, ME2, reporting by 2006. W1, W3, W4 1 FNQ NRM Ltd & Rainforest CRC (2004): Sustaining the Wet Tropics: A Regional Plan for Natural Resource Management, 2004 – 2008. FNQ NRM Ltd, Innisfail (208pp). 2 W = Water Resource Targets & Actions; L = Land Resource Targets & Actions; B = Biodiversity Targets & Actions; CB = Community Targets & Actions

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Table AD-2. Range of tasks defining management actions. Refer to section 4.8 for explanation of category MANAGEMENT ACTION RESPONSIBILITY TIME INVESTIGATION EXTENSION ON-GROUND

IMMEDIATE CATEGORY

Sewage management Maintain present schedule to Douglas Shire Council Completed in 6-7 Monitor planned sewage upgrade effluent disposal as years upgrades. outlined

Connect village septic systems to Douglas Shire Council Completed in 10 Monitor planned sewage Mossman STP, plus connection to years connections Mossman STP or a stand-alone system for Wonga Beach.

Sugar Cane - Nutrient Management Reduce rate of application of Sugar industry Commenced Produce leaflet Establish trial sites where preferred form of N based on crop within 3 years; explaining costs and farmers have been using N requirements. completed within benefits of N reduction cane export +10% 10 years Encourage appropriate form of N Sugar industry Commenced Investigate less Develop scientific Establish trial sites where below surface/trash. within 3 years; soluble N fertilisers guide to action and subsurface N is applied and completed within losses from different N urea compared to other 10 years sources forms Optimise effectiveness of N Sugar industry Commenced Investigate means of Extend the Fertilizers Establish comparative trials through timing of application and within 3 years; maximising legume Manufactures Guide with split applications application methodology. completed within N and search for titled CRAFT as a basis applied underground 10 years further N fixing crops for application including cane Delivery of the EMS Pathways Fertcare program Negotiation with fertilizer Sugar industry Commenced As for b, above Negotiate to expand the Work with QDPI&F to manufacturers on slow-release within 3 years; MoU between Federal arrange for slow release

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fertilizers, plus negotiation with completed within Government and trials appropriate Government agencies 10 years Fertiliser Manufacturers on price difference support. to include financial Compare economics and support for slow release efficiency of slow-release N fertilisers

Observe present development of Sugar industry Commenced Investigate the Publicise varietal Check validity of low N low – N cane varieties for higher within 3 years; N/yield relations of differences and their claims and compare utilization in the Douglas Shire completed within identified low N significance by leaflets varieties at MAS variety Council. 10 years varieties and shed meetings plots

Support soil testing to determine Sugar industry Commenced Investigate Write up extension Gain farmer support for plant requirements other than within 3 years; commercial pricing booklet which gives twice-a-year analysis at Mill Nitrogen, which has taken into completed within of mill mud when both costs and yield laboratory as proposed for account mill mud and fallow 10 years mixed with balancing effects of fertilizer 2003/4 legume. nutrients applications based on regular soil analyses Case study on soil testing to Sugar industry Commenced As above Use block results of farmer demonstrate fertilizer within 3 years; case study with long history effectiveness. completed within of analysis on fertilizer 10 years variation

Sugar cane – Shallow drain management Develop and implement a work Sugar industry Completed Investigate cost- Hold field day to • Complete study of program, which includes the within 7 years effectiveness options demonstrate benefits of location of eroding drains ranking of drains works in each for drain design and swales and grassed where depth, slope and catchment to reduce erosion of stabilisation areas. Produce photo cover require corrective shallow field drains by converting set and procedures on stabilisation. to grassed swales with sufficient drain rehabilitation headroom to operate machinery • Develop a process across paddocks. for corrective stabilisation

Develop a working group Sugar industry Completed Investigate cost- • Establish drain involving all stakeholders that within 2 years sharing options for study group to evaluate includes Douglas Shire Council drain design and local

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and landholders to plan stabilisation application/modification of information and corrective action recent detailed program. Negotiate cost sharing recommendations from arrangements with government. Herbert/Johnstone on drain stabilisation. • Based on the above commence a program of prioritising work’s programs.

SUPPORT CATEGORY

Tourist Boats Reduce boat wake by river tour River tour operators Commencing Investigate options in Provide extension to • QEPA to enforce operators & Environmental immediately design to reduce operators on compliance to speed limit in Protection Agency wave wake objectives to marine reserve areas. maintain speed limits Dispose of effluent to land-based Marine tour operators By 2007 • DSC have STP to accept repository & Department of saltwater functional by Transport & Regional 2007 Services • Operators retrofit plant equipment for pumpout • State Agency responsibility to enforce compliance Aquaculture Have aquaculture enterprises Aquaculture industry, Commence the Provide fact sheets • QEPA to consult and discharge wastewater that comply to Environmental process of for aquaculture negotiate cooperatively with Water Quality Objective for Protection Agency & compliance enterprises under 5 ha enterprises that have adjacent watercourse reach Douglas Shire immediately that are a Consent discharges to introduce any Council Development changes to license conditions in a fair and timely manner Provide fact sheets

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for aquaculture that would comply with Water enterprises over 5 ha Quality Objectives. that are an Environmental Relevant Activity

Sugar cane – Deep drain management Develop an implementation Sugar industry Completed Investigate cost- Hold field day to • Complete study of program, which includes the ranking within 10 years effectiveness for deep demonstrate stable location of eroding drains of drains works in each catchment to drain design and drains. Produce where depth, slope and cover reduce slumping by sloping and stabilisation photo set and require corrective stabilisation. grassing of drain-walls (hard armour procedures on drain • Develop a process for where necessary), plus mechanical rehabilitation corrective stabilisation and vegetative stabilization of drain- head erosion. Develop a working group involving Sugar industry Completed Investigate cost- Hold field day to • Establish drain study all stakeholders that includes within 4 years sharing options for demonstrate stable group to evaluate local Douglas Shire Council, landholders deep drain design and drains. Produce application/modification of and Main Roads to plan information stabilisation photo set and recent detailed and corrective action program. instructions on drain recommendations from Integration of drain planning at rehabilitation Herbert/Johnstone on drain boundaries essential. Subsidies stabilisation. from government need to be • Based on the above negotiated. commence a program of prioritising work’s programs.

Coastal floodplain – Wetland functionality Establish functionality of existing Land managers, Commence Investigate condition Promote through Assessment of potential sites wetlands and construct wetlands regional NRM Board immediately ratings for existing literature the benefits based on GIS analysis of basing priority on maximising wetlands in the shire of wetlands in the factors such as drain densities, capture of pollutant load at end of shire digital elevation modelling, drainage pattern crop layer, crop yields, soil type and watercourse layers.

Improve functionality of

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existing wetlands by utilizing appropriate technique.

Construct new wetlands for capture of pollutant loads.

Facilitate ecosystem service payments to landholders

LONG TERM

Sewage management 1. Gradual phase-out of rural Douglas Shire Completed in 10 Investigate cheaper Produce and circulate Develop pump-out data base residential septic systems with Council and land years low energy waste details of financial for compliance measures appropriate alternatives residents disposal systems support or replacement toilet systems 2. Develop proposal for cost- Douglas Shire As above, initiated by As in b sharing of alternatives. Council DSC with State support

Storwater Management Implementation of current Douglas Douglas Shire Completed Investigate sediment Ensure all building Survey current urban Shire Council’s Erosion Control & Council within 7 years prevention and contractors have, and runoff/erosion situation and Stormwater Management settlement plus adhere to, erosion recommend on priority sites, Development Guidelines. nutrient removal or control methods. including installation of redistribution for the Implement fine retention/settlement ponds wet tropics system for non- compliance Implementation of all Queensland Douglas Shire Investigate grey Survey private householders guidelines on reducing domestic Council water reuse options as done for accommodations pollutants. under local by JCU study (Carmody 2004) conditions

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Development Site Control Introduction of tighter compliance Douglas Shire ongoing Undertake awareness Undertake site inspections to the Environmental Protection Council program via site prior & during wet season. (Water) Policy, 1997 visits and distribution of guidelines

Sugar Cane - Fallow Promote the use of a legume fallow Sugar Industry • Trial & • Hold field • Determine a cropping. document species of days to demonstrate successful process for crop Combine with below 2 legume suited &/or benefits of legume establishment. various hybrids of rotations. • Ensure cooperation soya on varying • Demonstrati of legume producers. paddock conditions. on of suitable • Investigate planting systems. to a greater detail the cost effectiveness of legume fallow & weed management • Investigate the means of harvesting legume for grain as well

Further work to be undertaken to Sugar Industry Investigate more Use farms where provide an effect technique to direct versatile trash planter direct drilling of drill into trash. legume into trash has Combine with above succeeded as in field days, eg Sugar Awareness Day Promote the practice of fallow Sugar Industry • Investigate/d • Field day Establish mechanism for planting vs plough-out/replant. ocument cost promoting the getting growers into fallow Combine with above. effectiveness of cost/benefits of system fallow plant in MSM fallow plant vs • Investigate plough-out/replant incentives available • Identify

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to growers to move impediments to from plough-out to adoption fallow plant • Direct specific programs to overcome impediments, including demonstrations

Quarrying Introduce stricter controls over Douglas Shire ongoing Undertake awareness Undertake site inspections permits for quarries under 5,000m3 Council program via site prior & during wet season. to comply to the Environmental visits and distribution Protection (Water) Policy, 1997 of guidelines Maintain licence conditions on QEPA quarries over 5,000m3

Grazing a) Maintain dense groundcover for DPI&F, Agforce, ongoing DPI&F & DSC to (i) There will be a (i) Undertake survey by slopes and plains through land managers instigate the requirement to seek grazing study group of appropriate stocking rates, incorporation of DPI extension service locations where productivity watering distribution and generated paddock to assist the delivery and stability currently occurs. fencing. assessment into to the landholder of b) Implementation of Farm Douglas Shire’s GRAZING a) i. Gain agreement on Management System SedNet. onground (i), (ii) & corrective action. (iii) ii. The intent of this group (ii) Produce graphic will be to provide the examples and ability for self-assessment descriptions of of paddocks to occur to grazing condition ascertain the 3 p’s classes for landholder 1 Palatability field evaluation 2 Production 3 Perennial Develop a

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coordinated series of iii In delivery, the focus is field days involving not water quality, however land management there is an obvious water decision makers, quality benefit of having better including cover. landholders, DPI, DSC, DNRMW, QEPA, NRM Board Pty Ltd and downstream stakeholders Undertake the best endeavors to Land managers, Completed by • Mapping of • Arrange • Consideration of the minimise erosion of river and creek DSC, River 2010 instability risk areas field trips to other practicability of off-stream banks with attention to causes and Improvement Trust and suggested Shires where this watering points for different cost-sharing and Regional NRM appropriate solution has situations, but with the intent Board stabilization method succeeded. of restricting access of stock to for each risk class. • Arrange for a watercourse. off-stream watering • Establish cost-sharing • Investigate point demonstration of off-stream watering points actual rate of bank site and hard surface access that erosion at active • Produce has recognised the public good sites. guide which analyses gained. costs and benefits for • Provision of well • Investigate appropriate located, stable access to on- cost sharing options management of stream water points. and public benefits of watercourses and • Vegetative and this combination of explains incentives mechanical bank stabilization, practices available. with maximising vegetative • Develop a and “soft engineering” coordinated series of solutions wherever possible. field days involving Sites recommended from land management GRAZING (b) Research (i) decision makers, • Adopt appropriate including cost-sharing arrangement for landholders, DPI, vegetative and mechanical

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DSC, DNRMW, bank stabilization. QEPA, NRM Board • Removal or Pty Ltd and realigning program of snags downstream identified in GRAZING (b) stakeholders Research (i) and subsequent DNRMW annual inspections.

Season and frequency of burning to (i) Investigate • Establish (i) Establish trials to compare plan to minimise run-off and burning season effect study group to meet current practice with spring erosion. on soil loss. with researchers on burning (moist soil) and alternatives and plan herbicides for regrowth. action research. • Develop a coordinated series of field days involving land management decision makers, including landholders, DPI, DSC, DNRMW, QEPA, NRM Board Pty Ltd and downstream stakeholders. Determine soil losses from hillslope Research institutions Completed by • Initiate (i) Promote field Establish soil loss plots on erosion 2010 research of days and invite grassland and forest slopes. vegetation type and cooperation to trial management on alternative burning runoff/erosion. regimes. • Produce research model using published runoff data from comparable cover/slope situations.

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• Incorporate findings into Douglas Shire’s SedNet.

Horticulture Land managers adopt priority BMPs Horticultural industry Completed by Investigate critical Provision of Facilitate incentive programs in all horticultural crops with the 2010 priority BMPs extension to aiding landholders in the Farmcare – Cultivating a Better maximise adoption of implementation of priority Future being the driver. priority BMPs by BMPs short courses and demonstrations

Forestry Encourage the adoption of CoP for Land managers Investigate suitable Extension service forest activities on private lands converting land to forest species for a that provides farm forestry range of situations in sustainable this shire techniques in, • establishment • silviculture • harvesting

Riparian Management Since bank erosion is a source of Land managers, Completed by Investigate cost- • Develop Finalise identification of sediment the physical stabilization DSC, River 2010 effectiveness of appropriate unstable bank locations. of banks by engineering and Improvement Trust locally adapted mechanisms for Extend landholder riparian vegetative methods requires special and Regional NRM stabilisation local ownership of agreements as circulated attention, especially where overbank Board techniques, building remediation actions September 2004 flow cannot be reduced. See on outcomes of the that includes recommendations under grazing. DSWQIP plus from logistics and funding Identify and commit to the Tully & support. coordination of onground Johnstone. • Employ a range of works existing videos on riparian rehabilitation to

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spread information to local landholders. Arrange field days. • Regional NRM bodies and River Improvement Trust to develop closer links to ensure compatible and co- ordinated planning, actions and work programs.

Roads Establishment of an environmental Douglas Shire DSC produce special Survey and map priority road- funded road-sealing program. Council environmental road sourced sediment funding application to government Map and prioritise roads based on Douglas Shire Investigate rapid Develop Shire road As in a). impact of sediments reaching Council assessment method of sediment control plan watercourses requiring sealing. identifying road to gain landholder sediment sources and cooperation corrective action Promotion of separate road drain Douglas Shire Investigate cost- Promote coordinated Recommend locations for management plans with duel Council & Main sharing options road sediment action application of techniques in objectives of efficient drainage and Roads between local program for each Main Roads most recent soil stabilization. government and state. sub-catchment. sediment control guidebook Link to Roads to Agree on a (2004) Recovery federal landholder program. coordinator in each area. Design of construction and DSC/WTMA Investigate role of Circulate leaflet to Survey eroding steep private maintenance program and guidelines geotechnical-fibres affected landholders roads and offer engineering for steep private roads. and porous cover offering erosion guidelines (DSC/WTMA)

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material for steep control ideas and roads/drains cost-sharing

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