ACT Water Report
2001–2002
ACT Water Report 2001–2002 (Revised)
FURTHER INFORMATION
Complete data for all of the sites reported is available from the Internet under the Environment ACT Government website at: g www.environment.act.gov.au/ie4/airandwater/water.html
Should you wish to seek further information in relation to this report, please contact: g Andrea Garnsey Environment Protection Environment ACT Telephone: 6207 2350 Facsimile: 6207 6084 E-mail: [email protected]
© Australian Capital Territory, Canberra 2002
This work is copyright. Apart from any use as permitted under the Copyright Act 1968, no part may be reproduced without the written permission of Business Development and Marketing, Environment ACT, PO Box 144, Lyneham ACT 2602.
Published by Environment ACT (EMC 02/1042)
Environment ACT Helpline: 6207 9777 Environment ACT Website: www.environment.act.gov.au
ii Environment ACT ACT Water Report 2001–2002 (Revised) Contents Executive Summary ...... 1 Introduction...... 2 Purpose...... 2 Scope ...... 2 Land Use...... 2 Climate ...... 3 Streamflow...... 4 Rivers in the ACT Region...... 5 Protection of Water Resources ...... 5 The Territory Plan Environmental and Use Values ...... 5 Water Quality Standards...... 6 Water Resource Use ...... 6 Water Monitoring Program ...... 8 Sampling Sites...... 8 Water Quality Condition...... 10 Analysis ...... 10 Current Status—Reporting Methodology...... 10 Water Quality Status...... 10 Long Term Trend ...... 10 Indicators...... 11 Biological Monitoring...... 11 Nutrient Levels...... 14 Suspended Solids...... 14 Faecal Coliforms...... 15 Turbidity ...... 18 pH (Acidity and Alkalinity)...... 18 Ammonia...... 18 Dissolved Oxygen...... 18 Chlorophyll ‘a’ ...... 18 Algae Monitoring...... 19 Lakes...... 23 Lake Tuggeranong...... 23 Point Hut Pond (Site 270)...... 23 Gungahlin Pond ...... 24 Lake Ginninderra ...... 24 Rivers ...... 25 Ginninderra Creek ...... 25 Paddys River (Site 842)...... 25 Gudgenby River (Site 901) ...... 26 Murrumbidgee River ...... 26 Molonglo River...... 27 Water Resources Use...... 28 Water Related Projects ...... 33 Research into the Local Macquarie Perch Population...... 33 General Information...... 33 Radio Tracking Macquarie Perch ...... 33 Macquarie Perch in Paddys River ...... 34 Monitoring of Macquarie Perch Across the ACT Region...... 34 Waterwatch...... 35 Getting Involved in Waterwatch...... 36
iii ACT Water Report 2001–2002 (Revised)
Integrated Catchment Management...... 36 Riparian Projects Undertaken by Community Catchment Groups...... 37 Riparian ACTion...... 37 Appendix 1 – Charts Illustrating River Flow in Three Climatic Regions...... 39 Appendix 2 – Assessment Methodology...... 40 Comparisons with Standards ...... 40 Long Term Trend ...... 42 Appendix 3 – Biological Monitoring Results ...... 43 Appendix 4 – Results from Sampling Sites ...... 44
List of Figures Figure 1: Land Use Map...... 3 Figure 2: Monthly Average Rainfall in Belconnen near Barton Highway ...... 4 Figure 3: Average Monthly Flow in the Murrumbidgee River Near Angle Crossing ...... 4 Figure 4: Average Monthly Flow in Ginninderra Creek Near Charnwood Road...... 5 Figure 5: Water Catchments Map ...... 7 Figure 6: AusRIVAS Assessments of Monitoring Sites in the ACT for Spring 2001...... 12 Figure 7: AusRIVAS Assessments of Monitoring Sites in the ACT for Autumn 2002...... 13 Figure 8: Total Nitrogen Map ...... 16 Figure 9: Total Phosphorus and Suspended Solids Map ...... 17 Figure 10: Coliforms and Turbidity Map...... 20 Figure 11: pH and Ammonia Map ...... 21 Figure 12: DO and Chlorophyll 'a' Map ...... 22 Figure 13: Lake Tuggeranong at Kambah Wetlands ...... 23 Figure 14: Total Phosphorus and Ammonia in Point Hut Pond ...... 24 Figure 15: Suspended Solids and Conductivity at Gungahlin Pond ...... 24 Figure 16: Turbidity in Lake Ginninderra at Inlet and Outlet...... 25
List of Tables Table 1: Water Quality Standards (Ref: Environment Protection Regulations 1997)...... 6 Table 2: Flow Percentiles for River Sampling...... 8 Table 3: Macro invertebrate Sites ...... 9 Table 4: Licences to Take Groundwater by Catchment...... 28 Table 5: Licences to Take Surfacewater by Catchment ...... 29 Table 6: Combined Licences to Take Both Surfacewater and Groundwater by Catchment ...... 29 Table 7: Number and Volume Allocations by Catchment ...... 30 Table 8: Actual Releases from Water Supply Dams Compared with Environmental Flow Requirements for Period 1 April 2001 to 31 March 2002...... 31 Table 9: Water Drawn for Urban Supply from Cotter and Googong Catchments During 1 April 2001 to 31 March 2002...... 32 Table 10: Number of Macquarie Perch Caught 1996-2001...... 34
iv Environment ACT ACT Water Report 2001–2002 (Revised)
EXECUTIVE SUMMARY
Environment ACT manages a water monitoring and assessment program for the ACT that includes water quality, streamflow monitoring, and biological monitoring. This information is used to determine whether management strategies used to achieve or maintain the aquatic values set for ACT waters are appropriate.
The report is intended to provide the community with information regarding the state of water resources in the ACT. The assessment approach adopted is designed to move towards a more holistic ecosystem health monitoring system as prescribed by the Murray Darling Basin Commission’s Sustainable River Audit. It uses biological data to ascertain ecosystem diversity, water quality data to determine trends that may be present and compares these results with the designated environmental and use values and standards set in the Territory Plan and Environment Protection Act 1997 and its regulations. Streamflow monitoring is used to gauge the impact of removing water from the environment for other uses.
Water quality is monitored in the major urban lakes (with the exception of Lake Burley Griffin, a Commonwealth responsibility) and Burrinjuck Reservoir, which is immediately downstream of the ACT. The major rivers and some urban streams are also monitored. River flow is measured at a number of sites throughout the ACT.
Rainfall for the 2001-2002 reporting period was below the long term average. Streamflow measured in the major streams and rivers was generally below the long term average.
The report uses the biological information to report the biodiversity in the rivers. The sampling data is analysed, determining any trends that may be present for the period 1992-2002. The individual data points and median values for the year are considered with reference made to the standards set out in the Territory Plan and Environment Protection Act 1997. For flow dependent indicators, a flow concentration relationship is also used for comparison with the standards.
Lakes and streams in the ACT are in relatively good condition. The main impacts on water quality in the urban area appear to relate to land development with urban run-off carrying suspended sediment and nutrients.
Lake Ginninderra water quality is good, with a discernible improvement in water quality conditions through the lake, and thus in the water that is released into Ginninderra Creek. Conditions in Lake Tuggeranong are fair. Sediment and turbidity as well as nutrient values remain high, caused primarily by urban runoff. Point Hut Pond has poor water quality with elevated levels of turbidity and suspended solids. Runoff from residential development in the Point Hut catchment is the most probable cause.
Water quality in the Molonglo River was also good with the median values comparing favourably with the water quality standards at monitored sites. Water condition in the Murrumbidgee River remains quite good showing that the ACT has minimal impact on the water quality in the river and land use practices appear to be fairly effective in minimising pollution from the ACT. Paddys River catchment is a combination of rural, forestry and conservation land uses. The water quality for Paddys River is fair.
For the first time some information is included on water resources including the volume of water in our rivers and streams, and the quantity abstracted. The Water Resources Act 1998 came into full effect in December 1999 and requires assessment of river flows, and licensing of water abstractions. Since that time considerable progress has been made implementing the provisions of the Act. Most notably, all water use, except stock and domestic use from surface water is now required to be licensed. This includes all use from bores. Challenges remain, particularly in identifying all bores so that the Environment Protection Authority’s policy of accurately measuring all licensed water use can be implemented.
Environment ACT 1 ACT Water Report 2001–2002 (Revised)
INTRODUCTION
Purpose
This report is intended to provide the ACT community with information on the state of the ACT’s water resources for the year 1 April 2001 to 31 March 2002. To establish a statistically significant analysis of trends, the analysis includes data for the period 1992 to 2002.
The report is divided into four main sections. The first introduces the report and provides background information for interpreting the water quality data. The second section discusses water quality condition. The indicators used are introduced and results discussed for the lakes and rivers in light of the methods under consideration for the Sustainable River Audit commissioned by the Murray Darling Basin Commission (MDBC), the Territory Plan and Water Quality Standards. The third section provides monitoring information collected in administering the Water Resources Act 1998, which came into full effect on 11 December 1999. Finally, a brief discussion on projects undertaken by community groups in the ACT during the reporting period is also presented.
Scope
The report focuses on the major waterbodies of the ACT with the exception of Lake Burley Griffin. Water use from the Cotter catchment is included in this report but, in view of the generally undisturbed nature of the Cotter catchment, water quality monitoring is not discussed. However, as part of its licence to take water, ACTEW is undertaking a major monitoring program in the Cotter and Queanbeyan water supply catchments. It encompasses physical, chemical, biological, and fish components and is supporting a major investigation into environmental flows being undertaken by the Cooperative Research Centre for Freshwater Ecology. Outcomes from this study will be included in future Water Reports. Drinking water quality, which is the responsibility of ACTEW and the Chief Health Officer, is not part of this report.
Lake Burley Griffin is a Commonwealth responsibility and is the subject of an annual report produced by the National Capital Authority.
Land Use
There are four major land uses in the ACT (Figure 1). Conservation land use tends to have a minimal impact on water quality. Plantation forestry and rural use can have significant impacts on water bodies where these activities result in soil erosion or the release of agricultural chemicals and animal waste. Urban use has the greatest potential for impact on water quality per unit area. Materials entering urban waterways, which are likely to impact on the health of our waterways, include fertilisers and other chemicals, organic matter, soil, oil, and sewage effluent.
2 Environment ACT ACT Water Report 2001–2002 (Revised)
Figure 1: Land Use Map
Climate
Rainfall in the ACT is strongly affected by the landform. In the mountainous region to the west of the Murrumbidgee River, annual average rainfall ranges from 800-1000 mm. The flatter tablelands on which Canberra is built are in a rain shadow area and the annual rainfall reaches 600-700 mm.
The ACT Government measures rainfall at a number of sites in the ACT. Rainfall for a site in Belconnen near the Barton Highway (Figure 2) shows both the monthly average rainfall for the 2001- 2002 reporting period as well as the long term monthly average.
Environment ACT 3 ACT Water Report 2001–2002 (Revised)
Figure 2: Monthly Average Rainfall in Belconnen near Barton Highway
200
160
120
80 Rainfall (mm)
40
Long Term Trend 0 Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Actual 2001-2002
The long term average annual rainfall, since 1992, in Belconnen at the Barton Highway site is 712 mm. The annual rainfall for this reporting period was around 580 mm and less than the 741 mm recorded during the period 1 April 2001 to 31 March 2002. The rainfall data show an irregular rainfall pattern, with extremely high falls during February and low monthly falls for most of the reporting period.
Streamflow
Streamflow during the period at most gauging stations was generally below the long term average. Different flow patterns can be seen for streams in the different climatic regions of the ACT. This is shown in detail in Appendix 1.
Flow in the Murrumbidgee River near Angle Crossing, shows that the mean monthly flow into the ACT only exceeded the long term average in August, September and February (Figure 3). Total average monthly flow for 2001-2002 was 25 GL compared with 29 GL for the previous 10-year period.
Figure 3: Average Monthly Flow in the Murrumbidgee River Near Angle Crossing
20
16
12
8 Flow (cumecs)
4
Long Term Trend 0 Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Actual 2001-2002
Urban areas react more quickly to rainfall with a greater proportion of rainwater being converted to run off due to the large impervious surface areas. Flows in Ginninderra Creek illustrate the elevated levels
4 Environment ACT ACT Water Report 2001–2002 (Revised)
of run off from the high rainfall events during February. Figure 4 shows how closely the run off matches the rainfall in Figure 2. A less developed catchment, responds more slowly to rainfall events.
Figure 4: Average Monthly Flow in Ginninderra Creek Near Charnwood Road
2.0
1.6
1.2
0.8 Flow (cumecs)
0.4
Long Term Trend 0.0 Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Actual 2001-2002
Rivers in the ACT Region
A number of the rivers and streams that flow through the ACT originate in NSW. The catchment boundaries of other major rivers in the ACT form part of the ACT/NSW border.
The Murrumbidgee River originates well to the south of the ACT. Tantangara Reservoir diverts its headwaters to the Tumut River and the river is further regulated downstream of the ACT at Burrinjuck Reservoir. The Molonglo River and Queanbeyan River rise to the south-east of the ACT with both draining through Lake Burley Griffin to the Murrumbidgee River.
The Cotter catchment forms the western boundary of the ACT and the Naas and Gudgenby catchments form the southern and south eastern boundaries.
Protection of Water Resources
The Government seeks to manage waterways so that sustainable and appropriate water conditions are attained. This includes an integrated catchment approach to planning, development controls, the licensing of end of pipe discharges and licensing of non-point source discharges through the requirements of erosion and sediment control plans. Urban stormwater management infrastructure such as gross pollutant traps, water quality control ponds, wetlands and vegetated floodways are designed and managed to reduce urban impacts on water quality, as is an increasing emphasis on improved urban design. These measures are designed to ensure that water quality is suitable for designated uses.
The Territory Plan Environmental and Use Values Part C2 of the Territory Plan, Water Catchment Policies, sets the permitted uses and protected environmental values for the waterways in the ACT. The Plan identifies three categories of water use and catchment policies. These are drainage and open space, water supply, and conservation. For each category a range of other uses are allowed which are generally compatible with, but secondary to, the primary value.
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Water Quality Standards Water quality standards are identified in Schedule 4 of the Environment Protection Regulations 1997. These regulations contain tables that list the necessary water quality to support each of the water uses referred to in the Territory Plan. Table 1 provides examples of some of the water quality standards for certain water uses.
Table 1: Water Quality Standards (Ref: Environment Protection Regulations 1997)
Water Use Indicator Water based Water based Water supply— Water supply— Aquatic recreation— recreation— stock irrigation habitat—wetland swimming boating (AQUA/1 to (REC/1) (REC/2) (STOCK) (IRRIG) AQUA/6) Total Phosphorus 0.1 0.1 0.1 (mg/L) Turbidity (NTU) not objectionable Not objectionable 10–30 Suspended Solids So as not to 12.5–25 (mg/L) block irrigation systems Chlorophyll ‘a’ 10 10 10 2–10 (µg/L) Algal Cells Counts 5,000 5,000 up to 10,000 5,000 (cells/mL) depending on species Bacteria (faecal 150 1,000 1,000 1,000 coliforms/100 mL) Dissolved Oxygen >4 (mg/L) Acidity (pH) 6.5–8.5 6.5–8.5 6.5–9.2 4.5–9.0 6–9 Total Dissolved 3000 500 Solids (mg/L)
Water Resource Use The Water Resources Act 1998 came into full effect in December 1999, providing the tools for the Territory to effectively and sustainably manage its water resources.
The Act provides for the preparation of Environmental Flow Guidelines that set out the methods used to identify flows necessary to protect all ACT waterbodies. While the guidelines have been developed on the basis of the best available scientific advice a number of pragmatic assumptions were necessary. In order that better information will be available when the guidelines are reviewed, and in light of the ACT Government’s partnership in the Centre, the Cooperative Research Centre for Freshwater Ecology is undertaking a major study into environmental flows in the Cotter River. The study should assist in the appropriate provision of environmental flows with the minimum impact on urban water supplies. As required by its licence to take water ActewAGL is undertaking a substantial monitoring program to provide input to the study.
The Act also requires the preparation of a Water Resources Management Plan which, on a catchment basis, describes the water resources of the Territory, quantifies environmental flows on the basis of the Environmental Flow Guidelines, identifies water available for use, and allocations which can be made over the next 10 years. Water catchments boundaries used for this purpose are set out in Figure 5. Both the guidelines and the plan are disallowable instruments and they came into effect in December 1999 and February 2000 respectively.
6 Environment ACT ACT Water Report 2001–2002 (Revised)
Figure 5: Water Catchments' Map
N Water Management Catchments under the
Parkwood Water Resources Act 1998 Gungahlin Water Mgt Catchments Urban Woodstock Lake 5 0 5 10 Kilometers Ginninderra Ur iar ra Sullivan's
Coppins Woolshed
Lake Burley Griffin Kowen Fyshwick Lower Cotter Weston Woden Kambah Jerrabomberra Lower Queanbeyan Tuggeranong
Paddy's Jerrabomberra Googong Headwaters
Bendora Tharwa Upper Molonglo Guise's Tennent
Burra
Cor in
Gudgenby Michelago Tinderry
Naas
The Water Resources Management Plan needs to be reviewed to update water allocations and to broaden the scope of the Plan. The Plan will become a strategic framework for the management of water resources in the ACT, as envisaged in the Water Resources Act 1998. It is anticipated that the Plan will include consideration of such elements as water sensitive urban design, water quality, the riparian zone and aquatic flora and fauna.
Appropriate environmental flows are maintained through water allocations and licensing. Water allocations are only issued in accordance with the Water Resources Management Plan and thus ensure that the total quantity of water that could be used from ACT water resources is sustainable. Licence conditions are used to ensure that water allocations are only taken from ACT water resources when and where the water is available (in accordance with the Environmental Flow Guidelines). Through these measures the use of the Territory’s water resources is now controlled.
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Water Monitoring Program
Environment ACT manages a water monitoring program for the ACT that includes the collection of water quality, streamflow and biological information. The monitoring program is based on regular sampling of lakes and rivers. Such information is used to determine whether waters in the ACT are of appropriate quality and if the management strategies used to achieve or maintain such water quality are adequate. The information is not intended to identify specific pollution incidents but provide information about changes to water quality over time.
The data for this report is sourced from Environment ACT’s water monitoring program, other government agencies and from authorised dischargers, including Lower Molonglo Water Quality Control Centre and Queanbeyan Sewage Treatment Plant.
Sampling Sites Sites are located so as to be representative of stream and lake conditions in the ACT. It is not possible to monitor all sites and all parameters of interest, consequently those considered most representative of environmental conditions are selected with the intention of generalising to other similar areas. The site locations can be seen on the water quality indicator maps (Figure 6 and Figure 7), for biological sampling and Figure 8 to Figure 12 for water quality sampling.
The major urban lakes (with the exception of Lake Burley Griffin — a Commonwealth responsibility) are sampled eight months of the year August, October to March and May. The sampling program for lakes is not flow related.
The ACT Government also monitors Burrinjuck Reservoir. The ACT's impact on the Murrumbidgee River is not identifiable downstream of Burrinjuck Reservoir as a result of the Reservoir's size and the residence time of water in it.
A separate program to monitor blue-green algae in Canberra’s lakes is undertaken during the summer months by Environment ACT.
A flow based sampling process has been adopted for the stream water quality monitoring program. This method is a more cost effective characterisation of water quality than time based monitoring, because streamflow is the major determinant of quality. Samples are collected within four flow percentile groupings (Table 2). The 5th percentile flow is the flow exceeded only 5% of the time and represents very high flow; conversely the 90th percentile flow indicates very low flow.
Streamflow is measured at a number of sites throughout the ACT. This information is valuable for interpreting water quality data. Most of the pollutants that wash off the land do so during rainfall events. In conjunction with water quality monitoring, streamflow allows for the calculation of pollutant loads in our lakes and rivers.
Table 2: Flow Percentiles for River Sampling
Flow Percentile Group Number of Samples 5–29 2 30–49 2 50–69 2 70–89 2
Rivers were sampled 10 times during this reporting period. In addition to the requirement to sample within flow percentile groups, there is a requirement to ensure there is a reasonable time period between each sample. The aim of this strategy is to provide a fully representative assessment of river health over time by taking account of the impact of flow on water quality.
The biological health of rivers was assessed using stream animals (macro invertebrates) as indicators. The selection of test sites was based on potential and known impacts from rural degradation, urban runoff, discharge of treated sewage effluent, trace metal contamination, habitat
8 Environment ACT ACT Water Report 2001–2002 (Revised)
degradation, sedimentation and river regulation. The three reference sites were selected from those sampled during previous rounds of the ACT component of the National River Health Program (NRHP). The 10 test sites and three reference sites were sampled in October 2001 and April 2002 (Figure 6 and Figure 7).
Table 3: Macro invertebrate Sites
Site No Location Site Type 40 Murrumbidgee River at Angle Crossing Reference 53 Murrumbidgee River at Halls Crossing Test 20 Gudgenby River at Smiths Road Crossing Test 58 Tuggeranong Creek downstream of Lake Tuggeranong Test 10 Paddys River at Murray’s Corner Reference 15 Tidbinbilla River at Paddys River Road Reference 242 Molonglo River at Sutton Road Bridge Test 70 Molonglo River at Coppins Crossing Test 235 Queanbeyan River below Queanbeyan Cemetery Test 246 Jerrabomberra Creek at Hindmarsh Drive Test 189 Yarralumla Creek at Cotter Road Bridge Test 195 Ginninderra Creek Test 64 Ginninderra Creek Test
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WATER QUALITY CONDITION
Analysis
Current Status—Reporting Methodology The condition of water bodies is reported using a number of methods. A review of the performance within the reporting year as well as the longer term trend is presented.
When assessing sites all the data collected since flow based sampling began in 1992 in considered. The long term performance of indicators is analysed with reference to flow, seasonality and time using the method set out in detail in Appendix 2.
The performance of each indicator is then considered for the reporting year 2001-2002. Median values were used in conjunction with statistical dispersion to consider conditions at each site, in relation to standards. The median is seen as the most useful measure of the ‘average’ condition as it is less affected by extremely high or low values than is the mean. The mean is strongly biased toward the infrequent extreme conditions that may occur in water bodies. Any significant variation of median from previous sampling years is noted.
For indicators that demonstrate a good relationship with streamflow, an additional method of analysis has been used to predict the number of occasions on which the indicator would have exceeded the standard. This relates to total phosphorus, total nitrogen, suspended solids and turbidity in rivers that all show an increase in concentration with increasing flow.
With a flow based sampling program, samples have been taken at various levels of streamflow. From the relationship between flow and the indicator, we can reasonably reliably determine the percentage of flows where an indicator may exceed the water quality standard.
Some sites have not been sampled at a sufficient range of flows as a result of natural conditions. For these sites it has not been possible to determine the percentage of flows the indicator would be exceeded.
Water Quality Status The condition of water quality at the monitoring sites can be assessed by comparison of actual concentrations with concentrations listed in the water quality standards (Table 1).
The data for the various indicators has been presented on a number of maps. Sites have been coded as good, fair or poor. A site is classified good when it compares well with the standards for the particular indicator. A fair classification indicates the value is on the threshold of the standards and a poor classification shows that a site noticeably exceeds the standards. The percentile of flow at which that indicator is likely to exceed the standard is also reported.
Long Term Trend Trend analysis of data available between 1992 and 2002 has been carried out for sites with sufficient data for trends to be detected. This period corresponds with flow based monitoring of rivers and creeks. Prior to this period, monitoring was carried out at regular intervals with no reference to flows, and it is not appropriate to compare these data.
All of the trend graphs have had a statistical test applied to determine if trends are significant. Statistical analysis was used on sites to determine the influence of flow as well as time on the concentration. The trendline produced is a product of that time component at the median flow. A detailed explanation of the method used is outlined in Appendix 2 and a scatter plot of all indicators at all sites is provided in Appendix 4. For the remaining river indicators and all lake sites, indicator concentrations have been plotted against time.
10 Environment ACT ACT Water Report 2001–2002 (Revised)
Indicators
Biological Monitoring The biological component of the ACT Water Quality Monitoring Program is based on the macro invertebrate monitoring undertaken using the AUSRIVAS protocol. It involves collecting samples from stream edges from ten test sites and three reference sites in the ACT region during spring 2001 and autumn 2002. An AUSRIVAS predictive model developed as part of the National River Health Program (NRHP) conducted under the Natural Heritage Trust has been used to assess these sites providing a measure of biological health.
The measurement presented in this report, O/E Site Band (five categories shown below) gives an indication of overall site condition. Sites at which more animals are missing are assessed as more impaired. The impacts are ranked as follows:
X Above reference A Equivalent to reference sites B Slightly impaired C Moderately impaired D Severely impaired
The results for spring 2001 and autumn 2002 are summarised in Figure 6 and Figure 7, with results presented in Appendix 3. Different factors have been impairing the biological health at different sites. Urban activity, agricultural and forest activities resulting in sediment addition leading to habitat degradation are major causes for reduced biological diversity. Poor results also occur where dam releases and disturbed environmental flows occur.
The low flow conditions during the reporting period at some sites such as 58,64,189,195,196 and 235 also had have an impact on water quality. There is significant impairment in Ginninderra Creek, with all sites in spring 2001 recording impoverished (Band D and C) results. It will be some time before the effect of the willow removal program, which has been undertaken to improve the ecology of the river by improving habitat diversity, is realised through improved biological health. However, the Autumn sampling suggested some improvement Figure 7). Slow but continued improvement as native vegetation establishes along the creek is expected.
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Figure 6: AusRIVAS Assessments of Monitoring Sites in the ACT for Spring 2001
% 53
196 $ 195 64ÚÊ ÚÊ
ÚÊ 189 242 246 $ $ # % 235 10 58 $ % 15
20 %40 Ñ
Spring 2001 Test Sites ÿ No assessment % A- equivalent to reference # B- below reference $ C - well below reference ÊÚ D - impoverished Ñ X - above reference
12 Environment ACT ACT Water Report 2001–2002 (Revised)
Figure 7: AusRIVAS Assessments of Monitoring Sites in the ACT for Autumn 2002
#$$ 53
196 # # 195 64 #
$ 189 242 246 # # # 10% 235 58 # 15%
40 20 # %
Autumn 2002 Test Sites ÿ No assessment % A-equivalent to reference # B-below reference $ C-well below reference ÊÚ D-impoverished Ñ X-above reference
Environment ACT 13 ACT Water Report 2001–2002 (Revised)
Nutrient Levels Nutrients are a natural component of all water bodies, but increases in their supply often have undesirable effects, including the eutrophication of aquatic ecosystems. Eutrophication is the presence of an abnormally high quantity of aquatic plant life and can include toxic algal blooms. This can also produce other unwanted side effects e.g. low dissolved oxygen levels in the water. The two most important plant nutrients for aquatic ecosystems are phosphorus and nitrogen.
In ACT waterbodies phosphorus is the nutrient that commonly determines the amount of algae that can occur. Total phosphorus is the sum of dissolved and particulate phosphorus in the water. The standard is 0.1 mg/L (Table 1). Median values ranged from 0.017 mg/L at Angle Crossing to 0.1 mg/L at Lake Tuggeranong near Kambah Wetland (Site 248) and at the Dam Wall (Site 249) as shown in Figure 9. The phosphorus level at Kambah Wetland and the main spillway at Lake Tuggeranong are high and the standard was exceeded on a large number of occasions.
Lake sites, with the exception of Lake Tuggeranong, had good phosphorus readings. For the river sites in which a relationship between flow and concentration could be determined, the maximum flow at which the standard was expected to be exceeded was the 4% flow at Gudgenby River.
There is no standard for total nitrogen for the ACT. Nitrogen is not generally a limiting factor in algal growth in regional waters and it is non-toxic to other organisms. Total nitrogen median value ranged from 0.26 mg/L at a number of sites to 12 mg/L at Sturt Island (Site 401) on the Molonglo River as shown in (Figure 8). This is considerably higher that the next median of 4.6 at the Northern Border (Site 224).
The levels of nitrogen measured at Sturt Island and the Northern Border are typical of waters downstream of a sewage treatment plant where plant discharge forms a high proportion of streamflow. In situations where nitrogen is limiting, research indicates a potential for the growth of nitrogen fixing blue-green (scum and toxicant forming) algae. In these situations, the discharge of nitrogen in sewage effluent will discourage the growth of nitrogen fixing blue-green algae. In addition, the discharge of nitrogen can have a beneficial effect by restricting the release of phosphorus from lake or reservoir sediments.
In this context, management and discharge authorisation arrangements in the ACT concentrate on minimising the input of phosphorus to waterways as a priority with nitrogen reduction encouraged as a second priority.
Most sites appear to have slight higher concentrations of both nitrogen and phosphorus compared with the last year. The drought that occurred in the last year or so will have reduced vegetation cover and resulted in increased erosion, carrying with it nutrients and sediments.
Suspended Solids All streams and rivers naturally carry some suspended material as organic and inorganic particles of varying sizes. Most land uses and activities have the potential to increase suspended solids concentrations in streams. An increase in the concentration of suspended solids can have two major impacts on aquatic ecosystems. Firstly, higher concentrations of suspended solids reduce the light penetration of water, retarding plant growth and changing the type of algae present. Secondly, increases in suspended solids concentrations ultimately result in increased sedimentation in streams and lakes, choking habitats for bottom dwelling organisms with sediment.
The standard for suspended solids ranges between 12.5 for the aquatic habitat value of mountain streams and 25 mg/L for lowland streams and urban lakes (Table 1). The standard of 25 mg/L was applied to all river sites as they are all categorised as lowland streams.
Suspended solids median values ranged from 1.8 mg/L at Gudgenby River (Site 901) to 31.3 mg/L at Point Hut Pond (Site 270) (
14 Environment ACT ACT Water Report 2001–2002 (Revised)
Figure 9). The water quality, with respect to suspended solids was poor in Point Hut Pond with a majority of samples taken comparing unfavourably with the standard. The cause of the high results is most likely due to development in the immediate catchment. However, median values tended to be higher than those recorded in the 2000-2001 reporting period, an effect that may be due to the dry season in the reporting period.
Faecal Coliforms Bacteria occur naturally in all waterbodies. The presence of faecal coliforms in a water sample may be an indication that human or animal faeces have contaminated the water and that harmful, less easily detectable pathogens such as Cryptosporidium and Giardia may be present. High levels of faecal coliforms are not necessarily a problem for aquatic ecosystems. Faecal coliforms generally do not infect aquatic organisms, and may serve as a food source.
The presence of high numbers of faecal coliforms is a problem for some human uses of water bodies, particularly water supply and recreation involving bodily contact. This report looks at bacterial levels in water used for primary and secondary contact recreational use, but does not deal with the quality of drinking water.
Results are expressed as colony forming units (cfu) per 100 mL. The standard for water based recreation–swimming is 150 cfu/100 mL and for boating and secondary contact is 1000cfu/100ml (Table 1). These standards apply to individual sites depending on their classification in the Territory plan. Median values ranged from 0 cfu/100 mL in Gungahlin Pond (Site 346) and Lake Ginninderra West (Site 318) to 240 cfu/100 mL at Ginninderra Creek (Site 301) as shown in Figure 10.
With the exception of Paddys River, faecal coliform levels generally compared favourably with the standard designated under in the Environment Protection Regulations. This provides some indication that land use planning and the quality of the ACT’s sewage system are protecting recreational opportunities. The 150 cfu/100ml standard for Uriarra Crossing (Site 207) has been exceeded a number times.
Environment ACT 15 ACT Water Report 2001–2002 (Revised)
Figure 8: Total Nitrogen Map
204 3 Ha lls Cross ing
# 301 - Ginninderra 0.9 Creek 346 # Gungahlin 1.0
# Pond - 224 4.6 Northern Border # 318 La ke 321 # 0.7 Ginninderra # Lake
Wes t Ginninderra 0.7
East 401 - # # Sturt 12.0 207 Island - 0.3 Ur ia rr a
Cross ing - 407 0.45 Coppins C#rossing
601 # Da ir y Fl at 1.6
608 Yass Road 0.3 # # 769 Queanbeyan 0.4 River
842
209 0.3 Paddys - # Ka mbah River # 0.3 - 248 Pool Ka mbah # Wet land 1.0 # 249 1.1 Lake Tuggeranong Da m Wa ll Total Nitrogen 270 # Point Hut 1.4 Pond (mg/L) Trend
- Increasing TN No Standard - Decreasing
901 - 0.3 Gudgenby River # 213 Angle 0.2 Crossing
#
1012345Kilometers
16 Environment ACT ACT Water Report 2001–2002 (Revised)
Figure 9: Total Phosphorus and Suspended Solids Map
0.03 204 Ha lls #
7 Crossing -
301 0.03 Ginninderra
Creek 8 - 346 0.03
# Gungahlin
# Pond -
- 17
0.03 224 - - Nor ther n -
# 0.03 318 321
Border
5 - La ke # Lake 0.03 Ginni nde r ra # Ginninderra - 7 Wes t East
18 # # - 401 0.07
Sturt 0.02 207 Island - Ur ia rr a 3 Cross ing
5 -
#
0.02 407 - - Coppins
4 Crossing 601 0.04 # Da ir y - Fl at 7 0.02 608 Yass Road 11
# # 769 Queanbeyan 0.03 River 7
209 0.03 0.03 842 # Ka mbah
Paddys # Pool 248 0.1 Total Phosphorus
River 9 Ka mbah 6 # - Wet land 10 # (mg/L)
0.1 249 - Lake Tuggeranong & Da m Wa ll 11 Suspended Solids
0.08 - 270 (mg/L) # Point Hut Pond 31 Symbol Standard
TP 0.1 Trend SS 25
- Increasing - Good Decreasing
Fair - Poor 0.03 901
Gudgenby# 2 River - 101234Kilometers 213 0.02 Angle Crossing # 5
Environment ACT 17 ACT Water Report 2001–2002 (Revised)
Turbidity Turbidity, or opacity of a water body is related to the suspended solids concentration but also includes colouration. A stream may have very low levels of suspended material but be strongly coloured, for example the tannin rich streams in Namadgi National Park. Turbidity has an important ecological effect in determining the depth to which light penetrates the water, affecting plant growth and changing the type of algae present.
Turbidity data are reported in Nephelometric Turbidity Units (NTU). To provide a sense of scale, water with a turbidity of 1 NTU is crystal clear, water at 5 NTU has a tiny trace of discolouration, and water at 100 NTU is brown and opaque. The standard is less than 10 NTU for rural streams and rivers and less than 30 NTU for urban lakes and ponds (Table 1).
Median turbidity values ranged from 3.9 NTU at Hall Crossing (Site 213) to 186 NTU at Point Hut Pond (Site 270) as shown in (Figure 10). The high turbidity at this site corresponds to the elevated suspended solid levels also experienced there.
Of all indicators, turbidity exceeded the standard most. Turbidity exceeded the standard for between 18% of flows at Ginninderra Creek to 58% at Paddys River (Site 842). Many medians are higher than the previous year, possibly as a result of reduction of vegetation cover in the ACT Catchment. However, they also reflect the effect of urban development on turbidity. pH (Acidity and Alkalinity) The pH refers to the degree of acidity or alkalinity of the water. A pH of 7 is neutral. A value above 7 indicates that the water is alkaline and a pH below 7 indicates acidic conditions.
The levels for pH at all sites are good. Very few samples fall outside standard values, pH 6.5–9 for rural streams and rivers and pH 6–9 for urban lakes and ponds (Table 1). All medians fall well within the acceptable range, as shown in Figure 11. Many sites also show a decreasing trend in long term data.
Ammonia Ammonia concentrations are generally related to the level of organic material in water as well as the presence of conditions conducive to the conversion of nitrogen compounds to ammonia. Levels of ammonia in streams may also be increased by discharges high in ammonia. The toxicity of ammonia (un-ionised component) is a function of the pH and the temperature of the water.
Ammonia median levels are generally low across all sites, with median ammonia concentrations ranging from 0.003 mg/L at Angle Crossing to 0.05 mg/L in Lake Tuggeranong at the dam wall as shown in Figure 11. The highest values are found in lakes, particularly Lake Tuggeranong and Point Hut Pond. The standard is calculated from a table and is dependent on the pH and temperature of the water at the time of the sample.
Dissolved Oxygen Dissolved Oxygen (DO) is a measure of the oxygen in the water available to aquatic organisms. It is important for the maintenance of aquatic organisms as changes in DO can affect the species present. Low levels of DO can stress fish, which can lead to fungal infections and disease or result directly in fish kills. Levels of DO are effected by turbulence, temperature (colder water can hold more dissolved oxygen), photosynthesis (during periods of sunlight algae and other water plants produce oxygen while in darkness they consume oxygen) and the level of biochemical oxygen demand.
Almost all sampled sites except at Gungahlin Pond and Paddys River compared favourably with the >4mg/L standard, which is applicable at all sites. Median DO concentrations ranging from 5.7 mg/L at Kambah Wetland to 10.4 mg/L at Angle Crossing River as shown in Figure 12.
Chlorophyll ‘a’ Chlorophyll ‘a’ is the plant pigment that gives algae their green colour, and is commonly used as a measure of the quantity of algae present (algal biomass). This measure can therefore serve as a useful indicator of the extent to which an ecosystem has been affected by nutrient inputs. There is no
18 Environment ACT ACT Water Report 2001–2002 (Revised)
standard for streams and rivers in the ACT while a standard of less than 10 µg/L applies for urban lakes and ponds.
Chlorophyll ‘a’ is measured in micrograms per litre (µg/L). To provide a sense of scale, water with a chlorophyll ‘a’ concentration of 1 µg/L will be clear, a concentration of 20 µg/L will be slightly green, and 100 µg/L very green and possibly with algal scums on the surface.
Median Chlorophyll ‘a’ concentrations ranged from 1.2 µg/L at Gudgenby River to 21 µg/L at Dairy Flat on the Molonglo River as shown in Figure 12. Chlorophyll standards were sometimes exceeded with Lake Tuggeranong and Ginninderra East recording fair water quality.
Increasing trends were experienced at a number of sites on the Molonglo and Queanbeyan rivers and Ginninderra Creek. These sites have particularly low median values for chlorophyll ‘a’ and represent relatively good water quality. A gradual build up of chlorophyll ‘a’ at these sites may be related to the increase in organic materials, suspended solids and total phosphorus in the water.
Algae Monitoring Blue-green algae are simple microscopic plants that live either in water or damp areas. They are usually found in low numbers. However, when environmental conditions are favourable their numbers increase rapidly creating a ‘bloom’.
Blue-green algae occurs naturally in most ACT water bodies, but usually in low numbers. Given the right environmental conditions, which includes warm weather, low rainfall and high nutrient levels, then algae may multiply rapidly to high levels.
Lake Tuggeranong experienced a blue-green algae bloom significant enough to close the lake for a short period during April 2002.
In September 2001 two dogs died after ingesting blue-green algae whilst swimming in Lake Ginninderra. As a result the public were advised to avoid entering the water at Lake Ginninderra were green scum was visible.
Environment ACT 19 ACT Water Report 2001–2002 (Revised)
Figure 10: Coliforms and Turbidity Map
65 204 5.8 Ha lls # - 4 Cross ing
301 240 Ginninderra Creek 7.3 0 # 346 # Gungahlin Pond 36.4
34 224 Northern - # 318 Border 0 La ke 321 1
Ginninderra # # Lake We- s t Ginninderra 401 36 6 East 31.5 Sturt # # Isla nd 207 19 Ur ia rr a Cross ing
407 64 Coppins Crossing #
601 38 # Da ir y - Fl at 4.45 100 608 Yass Road 14 # # 769 270 Queanbeyan River 5
12 330 209 - - 842 Ka mbah - Paddys # Pool 12 8
6.2 # 248 9.5 River - # Ka mbah Wet land 32 # 6 249
Lake Tuggeranong Faecal Da- m Wa ll 39 Coliforms
12 (cfu/100mL) # 270 Point Hut Pond 186 & Turbidity (NTU)
Trend Symbol Standard
- Increasing FC 150 * - T Streams < 10, Lakes < 30 Decreasing
65
901 Good - Gudgenby River # 213 34 7 Angle Cross ing Fair 5 - # Poor 10123 4Kilometers
20 Environment ACT ACT Water Report 2001–2002 (Revised)
Figure 11: pH and Ammonia Map
8.4 204
Ha lls - # 0.007 Crossing
301 7.8 Ginninderra Creek 0.010 8.8 346 Gungahlin # Pond
# 0.050 -
8.0 224 - 318 - Northern 8.4 La ke Border # Ginninderra 321
Lake 8.3 0.01 Wes t # - # Ginninderra - 0.01 East 0.03
# # 401 8.5 Sturt 207 Island
7.6 Ur ia rr a 0.02 - Cross ing
0.004 - -
7.5 407
# - Coppins Crossing 0.01 7.6 601 # Da ir y Fl at 0.02 7.5 608 Yass Road 0.01 # # 769 7.4 Queanbeyan River 0.01
7.9 7.5 209 842 Ka mbah Paddys # # Pool 0.01 248 7.8 9 0.01 River Ka mbah pH # Wet land 0.055 # 0.05045 & 8.0 249 Lake Tuggeranong
Da m Wa ll
0.05 Ammonia (mg/L)
- - Symbol Standard
7.8.65
# 270
- Point Hut - Streams 6.5 - 9, Lakes 6 - 9 Pond 0.04 pH NH3 N/A Trend
- Increasing
Good -
Decreasing Fair
Poor 7.6 901 Gudgenby # 0.01 River 8.0
213
1012345Kilometers Angle - Crossing 0.003 #
Environment ACT 21 ACT Water Report 2001–2002 (Revised)
Figure 12: DO and Chlorophyll 'a' Map
10.4 204 # Ha lls 18 Crossing
8.5 301 Ginninderra # 346 8.6 Creek 7.2 # Gungahlin Pond 4.3 224 # Nor ther n -- 8.3 318 Border La ke # # 8.1
Ginni nde r ra 321 5.2 Wes t Lake - Ginninderra 4.4 # # East 207 401 Uriarra Sturt Crossing Island
407 # Coppins Crossing
# 601 8.1 Da ir y Fl at 21.0 6.7 608 Ya ss Roa d - 2.6 # #
769 7.4 Queanbeyan River 4.5 9.3 209
10.0 842 # Ka mbah -
Paddys # Pool 6.0 - River # 6 2.3 248 # Ka mbah Dissolved Wet land 8.3 8 Oxygen (mg/L) 249 Lake Tuggeranong 5.0 Da m Wa ll & Chlorophyll 'a' (ug/L) # 270 8.6 Point Hut Pond 3.6 Symbol Standard Trend DO > 4
- Increasing - C 'a' Streams no standard, Lakes < 10 Decreasing
Good
9.4 Fair # 901 Gudgenby - 1.2 River 10.4 Poor 213 Angle # Crossing 6.0 -
1012345Kilometers
22 Environment ACT ACT Water Report 2001–2002 (Revised)
Lakes
Lake Tuggeranong Two sites are monitored in Lake Tuggeranong, one at the Kambah Wetland (Site 248) which is near the northern inflow to the lake and the other at the dam wall (Site 249).
Data collected since 1992 indicate trends for turbidity, suspended solids and conductivity decreasing at both sites. There was also a significant downward trend for total phosphorus and pH at the dam wall (Appendix 4).
The median values have also remained steady or decreased from the 2000-2001 reporting year for most parameters. Suspended solids median values are lower, 18.6 to 10.1mg/L at Kambah Wetland and higher 8.05 to 10.7 mg/L at the dam wall and ammonia has decreased from 0.06 to 0.05 at Kambah Wetland.
The median level for turbidity in the Kambah Wetland exceeds the standard and total phosphorus equals the standard. Other parameters’ median values comply with the standards at both sites. The site at Kambah Wetlands is immediately downstream of a gross pollutant trap and a major urban run off point. Road works construction adjacent to the sampling point may have contributed to the elevated levels of turbidity. A proportion of Chlorophyll ‘a’ samples at both sites have exceeded the standard every year of sampling, a result that may be influenced by the nutrient levels.
Lake Tuggeranong experienced a blue-green algae bloom significant enough to close the lake for a short period during April 2002.
Whilst long term trends show a continual improvement in the water quality of Lake Tuggeranong (Figure 13) the levels of nutrients and turbidity remain high.
Figure 13: Lake Tuggeranong at Kambah Wetlands
Conductivity Suspended Solids 400 trend trend 60 360
50 320
280 40 m
c 240 30 us/ mg/L 200
20 160
10 120
0 80 Dec-1988 Dec-1991 Jan-1995 Jan-1998 Jan-2001 Jan-2004 Dec-1988 Dec-1991 Jan-1995 Jan-1998 Jan-2001 Jan-2004
Point Hut Pond (Site 270) Water quality in Point Hut Pond is poor when compared with the standards set for its designated uses in the Territory Plan and other lake sites in the ACT. However, the long term trends indicate some parameters are improving with reduction in pH, total phosphorus and ammonia (Figure 14). There is also a decreasing trend for the dissolved oxygen present.
Point Hut Pond had the highest median value of all sites for turbidity and suspended solids. The majority of the samples taken exceeding the standard. Suspended solids and chlorophyll ‘a’ median values are higher than the 2000-2001 reporting period.
Residential development in the Lanyon Valley and particularly on the steep land of Amber Ridge in close proximity to the pond, construction work on the Conder Wetland feeding the pond and the new development on Eastern Valley Rise are significant contributing factors to the poor results. Controlling run off at the source is the most effective means to reduce the flow of sediments into the pond. The upgrading of the Condor wetlands may assist in reducing pollution problems in the future.
Environment ACT 23 ACT Water Report 2001–2002 (Revised)
Figure 14: Total Phosphorus and Ammonia in Point Hut Pond
Total Phosphorus Ammonia 0.35 0.30 trend trend 0.30 0.24 0.25
0.20 0.18
mg/L 0.15 mg/L 0.12
0.10 0.06 0.05
0.00 0.00 Oct-1992 Sep-1994 Aug-1996 Jul-1998 Jun-2000 May-2002 Apr-1992 Nov-1993 Jul-1995 Mar-1997 Nov-1998 Jun-2000 Feb-2002
Gungahlin Pond Water quality in Gungahlin Pond (Site 346) is fair with reduction in turbidity, total phosphorus, suspended solids, and conductivity since 1992. Median values for most indicators compared favourably with the standards and most median values were equal or less than previous years (Figure 15). Chlorophyll ‘a’, dissolved oxygen, pH, total phosphorus and suspended solids median values had increased since the 2000-2001 report. Turbidity median value of 36 NTU exceeds the 10 NTU standard.
There is still a significant level of development occurring upstream of this pond, which may be adversely effecting water quality. However, the reduction in suspended solids concentrations and is expected to continue as the catchment stabilises after the extensive development during previous years. Development controls and sediment retention ponds upstream of Gungahlin Pond also contribute to the improving water quality.
Figure 15: Suspended Solids and Conductivity at Gungahlin Pond
Suspended Solids Conductivity 140 540 trend trend 120 480
100 420 80 L 360
mg/ 60 us/cm 300 40
20 240
0 180 Aug-1993 Apr-1995 Dec-1996 Jul-1998 Mar-2000 Nov-2001 Jun-2003 Aug-1993 Apr-1995 Dec-1996 Jul-1998 Mar-2000 Nov-2001 Jun-2003
Lake Ginninderra Two sites are monitored in Lake Ginninderra, one near the inflow in the East Arm (Site 321) and the other at the outflow dam wall, or West Arm (Site 318). Water quality in the lake was good and generally better than the other lakes monitored. At both sites the data shows significant downward trends in total phosphorus, suspended solids, ammonia and conductivity. There was also an improvement in turbidity and dissolved oxygen at the West Arm, however, the dissolved oxygen at the East Arm (Site 321) shows a slight decreasing trend.
The site at the West Arm complies with standards. The east arm median values for all parameters have decreased since the 2000-2001 report except dissolved oxygen and ammonia, which has increased from 0.02 to 0.03, a value still within the standard. The median value for turbidity at the East Arm has increased from 28.85 to 31.45 since 2000-2001.
24 Environment ACT ACT Water Report 2001–2002 (Revised)
The improvement experienced between the inlet and outlet indicates that Lake Ginninderra is improving the water flowing through the lake. This is demonstrated by the suspended solids readings at both sites (Figure 16). The turbidity levels in the East Arm may be affected by the turbidity levels in Gungahlin pond, as well as the willow removal that has been occurring upstream of the lake. As the stream bank stabilises from these works the water quality should improve.
In September 2001 two dogs died after swimming in Lake Ginninderra. The results of investigations conducted into the deaths of the two dogs determined that the most probable cause was that both dogs died after ingesting blue-green algae. This particular type of algae is generally found in colder climates and competes well in poor light. The algae normally grows in mats on the bottom of a lake but under the right conditions it can detach and float to the surface. As the lake warms up towards the summer this form of blue-green algae degenerates and tends to disappear.
Figure 16: Turbidity in Lake Ginninderra at Inlet and Outlet
Turbidity East Arm (Inlet) Turbidity West Arm (Outlet) 120 60 trend 100 50 80 40
60 30 NTU NTU 40 20
20 10
0 0 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002
Rivers
Ginninderra Creek The monitoring site for water quality in Ginninderra Creek is at Parkwood (Site 301) below the confluence with Gooromon Ponds Creek downstream of the lake. The biological monitoring sites in Ginninderra Creek are Baldwin Drive bridge (Site 195), downstream of Lake Ginninderra (Site 196) and Latham (Site 64).
In spring 2001, all three biological sampling sites showed poor condition (band C and D). However, in autumn 2002 there is an improvement to band B. The healthier macro invertebrates population (i.e. a shift from the impoverished D and well below reference C to below reference B) is likely to be the result of improvements in water temperature, turbidity and suspended solids results.
The trend analysis on the water quality parameters indicates reduction in total nitrogen, conductivity and total phosphorus.
Water quality is good with median suspended solids values slight down from last year from 8.4 mg/L to 8.3 mg/L and turbidity down from 10 NTU to 7 NTU. Improvements in water quality over time in Ginninderra Creek are evident and expected to continue as the catchment stabilises after extensive urban development. Examination of the turbidity compared with flow showed that this site would compare unfavourably with the turbidity standard for 18% of the time. This is a reduction from the 42% experienced last reporting period, however, it still represents a significant water quality issue.
Paddys River (Site 842) Paddys River catchment is a combination of rural, forestry and conservation land uses. The water quality for Paddys River is fair. The biological monitoring site on Paddys River is Murrays Corner (Site 10) which is considered a reference site. Results for both biological sampling runs showed the stream to be in good condition. The trend analysis on the water quality parameters indicates an increase in faecal coliforms.
Environment ACT 25 ACT Water Report 2001–2002 (Revised)
Median values remained constant or decreased for most parameters. However, the faecal coliforms median value was higher when compared to the median from the previous reporting period, 330cfu/100ml exceeding the standard. This may be caused by agricultural practices in the catchment. There was also an increase in the turbidity median, and based on the streamflow concentration relationship the turbidity would have exceeded the standard of 10 NTU 58% of the time. The increased level of turbidity would cause some reduction in light penetration and associated plant and algal growth, but have only minor influence on macro invertebrates. To improve water quality the Paddys River Landcare group has undertaken a project to limit access of stock to the river.
Gudgenby River (Site 901) The Gudgenby River drains a rural catchment dominated by native forest. The biological monitoring at Smiths Road Crossing (20) for both sampling sessions was condition A, equivalent to reference, indicating good biological condition. Trend assessment was not conducted due to a limited data set. Generally indicators complied with the standards.
The turbidity median increased from the previous reporting period, through it continues to comply with the standard. Based on the streamflow concentration relationship the turbidity standard would be expected to be exceeded 41% of the time.
Murrumbidgee River The Murrumbidgee River runs through the ACT entering at Angle Crossing (213) in the south and is sampled at a number of locations including Kambah Pool (209), Uriarra Crossing (207), the Northern Border (224) and Halls Crossing (204), which is in NSW, downstream of the ACT. The biological monitoring sites for the Murrumbidgee are Angle Crossing (40) and Halls Crossing (53).
The biological condition for autumn and spring for both sites was below reference (B). Angle Crossing is a reference site, which may indicate that biological conditions may be naturally lower than expected throughout the sampling period or that the site itself has been impacted.
The trend analysis undertaken on the sites showed a significant decrease in pH along the length of the river. Ammonia showed a reduction at for the three southern sites as did conductivity at Angle Crossing and Kambah pool. Angle Crossing also has a decreasing trend for total phosphorus and a slight increasing trend for chlorophyll ‘a’. Total phosphorus at the ACT border is decreasing, while the turbidity at Halls Crossing and Angle Crossing is increasing.
Most water quality parameters along the river comply with the standard. Chlorophyll ‘a’ medians have increased since the 2000-2001 reporting year and concentrations tend to increase as the river passes through the ACT. Median values for total phosphorus, total nitrogen, faecal coliforms and conductivity also increase from where the Murrumbidgee enters the ACT to where it leaves.
The total nitrogen levels at Site 224 and Site 204 are affected by sewage effluent discharge. The median values for these sites are steady, following the increase experienced in the last reporting year. Higher conductivity may be partly due to the levels in the Molonglo River and the additional input of treated effluent at LMWQCC.
Conductivity median values have decreased since the previous reporting period, which was effected by low rainfall and flow. The pH readings all complied with standards and have remained in a similar range to the previous year.
Dissolved oxygen levels are good along the length of the river. Faecal coliform levels complied with the standard, the highest median value was 65 cfu/100 mL recorded at Halls Crossing.
Suspended solids and turbidity median values complied with standards. However, the suspended solids median at Site 209 has increased from 7.5 to 9.2 and turbidity median from 6.7 to 12. At this site the turbidity would be expected to exceed the standard 56% of the time, at Site 204, 38% of the time. Suspended solids at Site 204 exceeded the standard 17% of the time.
26 Environment ACT ACT Water Report 2001–2002 (Revised)
The typically good water quality experienced in the Murrumbidgee River indicates that land use and management practices, which include sediment retention ponds, authorised discharges and building development controls are effective in minimising the impact that Canberra has on the Murrumbidgee.
Molonglo River The Molonglo River is sampled at two sites above Lake Burley Griffin, Dairy Flat (Site 601) and Yass Road (Site 608), and two sites below the Lake, Coppins Crossing (Site 407) and Sturt Island (Site 401) before it enters the Murrumbidgee River. The biological monitoring site is at Sutton Road Bridge (Site 242).
The biological condition for the reporting period remained at below reference (B) which indicates fair river health. The long term trend since 1991 for suspended solids has shown reduction at all sites. Sites 601, 401 and 407 also show a downward trend in phosphorus, with Sites 401 and 407 showing a decreasing nitrogen trend. Downward pH and ammonia trends were also found at site 407 and a reduction in conductivity at 608. There was an increase in chlorophyll ‘a’ at 608.
Overall the water quality was good. The median values for all parameters comply with the standards and there were no significant increases in these values from previous years.
Turbidity was not measured in the Molonglo River downstream of the lake, as it is not part of the data required of ACTEW under the Authorisation for the LMWQCC. Historical data suggests that the concentrations of turbidity at the downstream sites are not significantly different from the upstream sites.
Water quality in the Molonglo River downstream of the LMWQCC appears to have remained relatively unchanged over the past eight years. The absence of an increasing trend in the amount of total dissolved solids is encouraging given concerns about rising salinity across the Murray-Darling Basin.
A standard of 1000cfu/100ml faecal coliforms applies to all sites on the Molonglo. This standard was only exceeded a few times in the reporting period, which shows an improvement from previous years where faecal coliforms, especially at sites downstream of the lake, were a cause for concern.
Environment ACT 27 ACT Water Report 2001–2002 (Revised)
WATER RESOURCES USE
To provide for effective management of water resources the Environment Protection Authority has determined that all licensed water use is to be measured. Thus all licences include a standard condition requiring the installation of a water meter (or some other approved measuring system). This is not always a straightforward matter due to the location and nature of existing infrastructure, difficulties in the supply of equipment, and personal circumstances of individual licensees. While the majority of licensees have now installed meters some follow up is still required particularly in on-going maintenance of meters.
Details of licences and allocations issued and water use are provided in Table 4 to Table 9. The catchments referred to in the tables are shown in Figure 5.
Table 4: Licences to Take Groundwater by Catchment
Annual use1 1/04/2001 to Licensed Volume 31/03/2002 Catchment Name No of ML ML licences Coppins 1 3 76.32 Fyshwick 8 55 20.6 Guises 2 4 2.7 Jerrabomberra 3 – Narrabundah/ Symonston 6 246 174.5 Woden Creek 0 0 0 Eastern Catchment 0 0 0 Kambah 3 14 10.2 Lake Burley Griffin 3 7.5 2.1 Lake Ginninderra 2 17 38.4 Naas 1 2 1.7 Parkwood 3 10 6.2 Sullivans 2 17 0 Tharwa 4 25 21.4 Tuggeranong 2 6 3.5 Upper Molonglo 1 2 0 Weston 1 6 0.5 Woden 2 186 139 Woolshed 2 6 0 Total 43 606.5 497.1
1 Licensed volume is unlikely to equal actual use in any one year as actual use is averaged over a three year period.
2 Prior to the implementation of the Water Resources Act, little metering of water was done outside of the water supply catchments. Allocations for existing users were set on the estimates of the users. Allocations include a review after three years so that the long term volume can be set based on several years of actual metered use.
3 Jerrabomberra sub-catchment divided into three zones as recommended in the Groundwater Yield Assessment in the Jerrabomberra Creek Catchment –February 2001 report.
28 Environment ACT ACT Water Report 2001–2002 (Revised)
Table 5: Licences to Take Surfacewater by Catchment
Annual use1 reported for Licensed Volume period 1/04/2001 to Catchment Name 31/03/2002 No of ML ML licensed Fyshwick 10 1139 696 Gudgenby 1 2 0 Gungahlin 1 309 293 Kambah 1 192 160 Lake Burley Griffin 1 83 0 Lake Ginninderra 2 184 311.2 Paddys 3 79 0 Parkwood 1 10 0 Tharwa 4 61 0 Tuggeranong 1 42 23.7 Uriarra 1 8 0.1 Woden 1 2 0 Woolshed 3 45 13.8 Corin 1 29700 67033 Bendora 21000 Tinderry 9200 Googong 1200 Burra 1600 Total 31 64856 68530.8
Table 6: Combined Licences to Take Both Surfacewater and Groundwater by Catchment
Catchment Name Licensed Volume Annual use1 reported for period 1/04/2001 to 31/03/2002
No of ML ML licensed Fyshwick 1 18 13.1 Gudgenby 1 24 0 Sullivans 2 295 165.1 Uriarra 1 10 11.3 Woolshed 2 182 0.5 Total 7 529 190.0
Environment ACT 29 ACT Water Report 2001–2002 (Revised)
Table 7: Number and Volume Allocations4 by Catchment
Catchment Name No of allocations Total Volume(ML) Bendora 1 21000 Burra 1 1600 Corin 1 29700 Fyshwick 8 92 Googong 1 1200 Gudgenby 2 18 Gungahlin 1 309 Jerrabomberra 1 20 Kambah 2 192 Lake Burley Griffin 1 83 Lake Ginninderra 4 201 Paddys 3 79 Parkwood 1 12 Sullivans 3 318 Tharwa 4 61 Tinderry 5 10280 Tuggeranong 1 42 Uriarra 2 18 Weston 1 6 Woden 2 39 Woolshed 5 152 Total 50 65422
4 An allocation is not needed where groundwater is taken from a lease dated before11 December 1998.
30 Environment ACT ACT Water Report 2001–2002 (Revised)
Table 8: Actual Releases from Water Supply Dams Compared with Environmental Flow Requirements5 for Period 1 April 2001 to 31 March 2002
Date Outflow Corin Dam Bendora Cotter Googong Dam Dam Dam
April Actual 5028 1294 1451 585 Required 595 1016 1451 588 May Actual 9362 1257 1312 1094 Required 676 1154 1648 851 June Actual 6597 1459 1649 1293 Required 855 1459 2084 1104 July Actual 3995 1020 1608 2027 Required 1808 930 2252 1475 August Actual 2419 2429 4030 1841 Required 3016 2640 4845 1691 September Actual 3629 5058 7907 1861 Required 3594 5200 7828 1767 October Actual 9057 4809 6706 2020 Required 2751 4695 6706 1543 November Actual 11292 2746 3741 1152 Required 1543 2619 3741 1005 December Actual 13072 1703 2432 736 Required 998 1703 2432 682 January Actual 6449 799 743 601 Required 468 799 1141 520 February Actual 463 538 3234 809 Required 361 616 880 666 March Actual 1409 616 966 621 Required 361 616 880 606 Total [ML] Actual 72772 23728 35779 14640 Required 17026 23447 35888 12498
5 Environment ACT has concerns that the method used to calculate the environmental flow releases for the Cotter River does not accurately reflect true stream flows in the catchment. The method will be reviewed in 2004 as part of the review of the Environmental Flow Guidelines.
Environment ACT 31 ACT Water Report 2001–2002 (Revised)
Table 9: Water Drawn for Urban Supply from Cotter and Googong Catchments During 1 April 2001 to 31 March 2002
Cotter Googong Total [ML] [ML] [ML]
April 5266 0 5261 May 5138 0 5138 June 4039 0 4039 July 3683 0 3683 August 715 3022 3737 September 3966 0 3966 October 4612 0 4612 November 6015 0 6015 December 8872 55 8927 January 4844 5028 9872 February 1773 2913 4686 March 1754 5343 7097 Total 50672 16361 67033
32 Environment ACT ACT Water Report 2001–2002 (Revised)
WATER RELATED PROJECTS
Research into the Local Macquarie Perch Population
General Information Macquarie Perch (Macquaria australasica) is a nationally endangered fish and is protected in the ACT and NSW. The current distribution of this species throughout south-eastern Australia is characterised by small and fragmented populations. It was once widespread but is now confined to upper reaches in more pristine areas, which are less subjected to agriculture and have less siltation and other habitat modifications. It mainly lives and breeds in cooler, clear mountain streams. Macquarie Perch is now restricted in the ACT to the Murrumbidgee River, lower Paddys River and the Cotter River, and also can be found in the Queanbeyan and Goodradigbee rivers in NSW.
Macquarie Perch is a moderately sized, deep bodied fish with large white eyes. The body colour is grey to black with a whitish underbody. They live for up to ten years with males reaching sexual maturity at two years of age and females maturing at three years.
Spawning occurs in late spring and early summer when water temperatures reach approximately 16.5°C with fish depositing eggs above riffles or fast flowing sections of the river. The eggs are then washed downstream where they lodge in gravel or rocky areas until hatching.
The diet of Macquarie Perch consists of small aquatic insect larvae, particularly mayflies, caddis flies and midges. Shrimps, yabbies dragonfly larvae and molluscs are also eaten.
Threats that have led to the decline of Macquarie Perch include habitat destruction and modification, overfishing, construction of dams and weirs, sedimentation, reduction of in-stream habitat, decline in water quality and interactions with exotic species. The Macquarie Perch Action Plan is available from the Environment ACT Information Centre on 6207 9777 or the Environment ACT Website: www.environment.act.gov.au.
Several of the Macquarie Perch populations in the upper Murrumbidgee River catchment are constrained by barriers (both natural and man-made), such as road crossings, causeways and piped culverts. This leads to fragmented populations and prevents expansion of their geographical range. Macquarie Perch are not bred in captivity so cannot be stocked to increase population size and range. The only methods for expanding the range of the species and potentially reconnecting fragmented populations is to physically move individual fish above and below barriers, or to provide fish passage past these barriers.
One such barrier on the Cotter River at Vanity’s Crossing was identified as suitable for the installation of a rock ramp fishway. The crossing consisted of a concrete ford with a drop of approximately one metre on the downstream side. Macquarie Perch are present in the 5.5 km of river below the crossing but could not gain access to the 27 km of river upstream. A rock ramp fishway has been constructed at Vanity’s Crossing with the aim of providing Macquarie Perch access to the upstream habitat.
Fishways have also recently been constructed on the Murrumbidgee River at Casuarina Sands and on the Cotter River near the Cotter campground, funded by Environment ACT. These will allow native fish in the river such as Murray Cod, Golden Perch and Macquarie Perch to move past these barriers.
Radio Tracking Macquarie Perch The project Fish Passage, Movement Requirements and Habitat Use for Macquarie Perch is investigating the movement patterns and use of habitat by Macquarie Perch in the Cotter River using radiotelemetry. Transmitters have been implanted in representative fish. At each ‘fix’ a series of habitat variables are measured including depth, velocity, substrate, distance from bank, and proximity to shelter. This study will assist in defining the movement and habitat requirements for the species, as well as, evaluating the species response to the environmental flow regime that was recently introduced in the Cotter River. This knowledge is crucial if Macquarie Perch are to be managed with the aim of improving their conservation status.
Environment ACT 33 ACT Water Report 2001–2002 (Revised)
Researchers at Environment ACT found no evidence of the anticipated spawning migration of Macquarie Perch out of Cotter Dam in October and November 2001. However evidence of at least some spawning was found in January 2002 in the form of early stage juveniles. During April 2002 the team implanted transmitters into another 10 adult fish. Radio tracking of these individuals is being used to examine the effects of environmental flow releases from Bendora Dam.
Macquarie Perch in Paddys River A fish survey of the middle and lower reaches of Paddys River was carried out to determine the status of Macquarie Perch in that catchment. Five sites were surveyed and at each site three sampling techniques were used, namely Fyke nets, light traps and backpack electrofishing. A total of 198 fish were caught, only five of which were Macquarie Perch. These five Perch were all caught at the one site, 500 metres upstream of the Paddys River junction with the Cotter River. All of the Macquarie Perch captured were small individuals and the lengths indicated they were approximately 15 months old.
The survey concluded that it is unlikely that there is a significant population of Macquarie Perch in the Paddys River. The absence of young-of-year Macquarie Perch suggested it is unlikely there is a reproducing population in the Paddys River. The individuals captured during this survey were probably animals dispersing upstream from the Cotter River. Macquarie Perch are known to be present in the Cotter River at Cotter Reserve and have often been recorded near the toe-wall immediately below Cotter dam.
Monitoring of Macquarie Perch Across the ACT Region The decline of Macquarie Perch in the Murrumbidgee River and the small distribution and population sizes in the Cotter and Queanbeyan rivers raises concerns about the long-term viability of these sub- populations. Another strategy designed to achieve the objectives of The Macquarie Perch Action Plan is to establish a long-term monitoring program capable of detecting changes in distribution and abundance. 2001 was the first year that an integrated monitoring program had been attempted, with all sites sampled in a single year. Previous monitoring for this species had been site or sub-catchment based. Six sites were monitored during February and March 2001, three sites on the Queanbeyan River, one site in the Cotter Dam, one site in the Goodradigbee River and one site in the Upper Murrumbidgee catchment. A total of 88 Macquarie Perch were captured, the numbers at each site being substantially lower than those captured in previous years (see Table 10).
Table 10: Number of Macquarie Perch Caught 1996-2001 Drainage(River) Site Year 1996 1997 1998 1999 2001 Queanbeyan Above Curleys 3 11 0 Falls ACTEW Pool 26 31 1 Hayshed 43 73 19 Cotter Cotter Dam 99 50 Goodradigbee Coodravale 0 0 3 2 0 (Wee Jasper) Upper Kissops Flat 53 55 18 Murrumbidgee
At the majority of sites it was the young-of-year fish that were missing although adult numbers had also declined. The decline of the Queanbeyan River population is particularly disturbing as the abundance of fish has dropped by 83% since the last survey of this population in 1997.
The population of Macquarie Perch at the Goodradigbee River reference site is obviously in severe decline and cannot be considered secure in the short term.
34 Environment ACT ACT Water Report 2001–2002 (Revised)
The reasons behind the decline across the region are unknown at this stage, although it is not site related as the decline was apparent across all sites.
Radio tracking and integrated monitoring of the regional Macquarie Perch population will continue. All information gained through these programs will aid in the sustainable management of Macquarie Perch populations, locally and nationally.
Waterwatch
Waterwatch is a community water quality monitoring program that aims to equip local communities with the skills and knowledge to become involved and active in the protection and management of their waterways and catchments.
Waterwatch is federally funded through the Natural Heritage Trust and is locally administered by Environment ACT. There are three part-time Waterwatch Coordinators who are employed by three different employers in three separate work locations: Lake Tuggeranong College, ActewAGL and the Ginninderra Catchment Group.
The Waterwatch network is made up of individuals, community and school groups who undertake a variety of biological and habitat assessments as well as physical and chemical tests to build up a picture of the health of their waterways and catchment.
Waterwatch groups have initiated many positive, community based conservation activities such as creek restoration, willow removal, removing litter from waterways eradicating weeds, drain stencilling, development of habitats, reducing the use of pesticides, fertilisers and other pollutants.
This year Waterwatch has been involved in many exciting new and ongoing catchment programs and groups including:
• working closely with the newly formed Southern ACT Catchment Group Incorporated. Waterwatch activities are being designed to encourage associated groups to become involved in the effective monitoring, evaluation and planning of Integrated Catchment Management activities;
• the Catchment Health Indicators (CHI) program. CHI is a three year NHT pilot program that aims to develop a method that can be used by the community to measure catchment health. CHI monitoring is continuing in the Ginninderra Catchment group, SWAMP (Sustainable Water Action Management Project), Friends of Tidbinbilla, Southern ACT Catchment Group and Sullivans Creek Catchment Group;
• the Quality Assurance/Quality Control (QA/QC) program. The QA/QC program aims to test the accuracy of Waterwatch monitoring equipment and participants;
• SWAMP monitoring in the areas including Woolshed Creek, Pialligo Brook, Reedy Creek, the Molonglo River from Burbong Bridge to the entrance of Lake Burley Griffin, Queanbeyan River below Googong Dam and Jerrabomberra Creek;
• National Waterweek activities. The main focus for the 2001 celebration was the Aquafest festival. Aquafest is held at Lake Tuggeranong College and consists of about 20 interactive water related educational exhibits and was attended by the many ACT Primary Schools;
• the annual Waterwatch Snapshot for water bugs and turbidity. The annual Waterwatch snapshot involves groups undertaking a local waterway health check by collecting and identifying macro- invertebrate and testing for turbidity; and
Environment ACT 35 ACT Water Report 2001–2002 (Revised)
• the Race Around the Catchment (RATC) photographic competition. RATC celebrates 10 years of the Waterwatch Network by encouraging Waterwatch groups to submit a photograph that reflects the beauty of Australia’s waterways and local catchment. There were 17 local entries.
Getting Involved in Waterwatch If you are interested in improving the health of your local waterway and meeting or forming a group of likeminded individuals you should begin by contacting the Waterwatch Facilitator.
The Waterwatch web site is located at www.act.waterwatch.org.au and features information on Waterwatch, resources, contact details and a library of relevant publications and fact sheets.
The Waterwatch Information Network is a regular information e-mail which promotes Waterwatch and water quality issues in the Upper Murrumbidgee Catchment. Membership is free and open to all people with an interest in catchment health. Contact the Waterwatch Facilitator for more information.
Nigel Philpott ACT Waterwatch Facilitator Environment ACT Tel: 02 6207 2246 Fax: 02 6207 6084 Email: [email protected].
Integrated Catchment Management
In early 2000, Environment ACT released a framework for the future management of natural resources in the ACT. The Integrated Catchment Management (ICM) Framework for the ACT was developed in consultation with a range of community and Government organisations. The framework recognises that integrated management of our resources is the most effective way of dealing with environmental issues. It also acknowledges the integral role played by the community in natural resource management.
Sub-catchment planning is one of the most effective tools for delivering ICM on the ground. It brings together community groups and also provides an opportunity for the community and Government to work closely together for the greater environmental good.
Two such plans have already been developed in the ACT—Ginninderra Creek Catchment Strategy and Sullivans Creek Catchment Plan. Both plans have been successful in attracting large amounts of money for environmental rehabilitation works, whilst also coordinating cooperative community involvement in resource management.
Environment ACT and the National Heritage Trust are sponsoring the development of sub-catchment plans for six sub-catchments in the ACT over the next two years, with Tuggeranong-Tharwa and Wooden-Weston Creek being the first sub-catchments. The Plans will eventually form an integrated network of sub-catchment plans across the ACT, to be implemented by resource managers.
The first editions of the Tuggeranong-Tharwa and Woden-Weston Creek sub-catchment plans have been developed in consultation with the community and Government and will be published by the end of 2002. Community groups within these sub-catchments have formed an umbrella Southern ACT Catchment Group to further integrate their activities and progress the plans. In addition work has started on the development of a plan for the rural areas south of the Murrumbidgee. This will enable rural issues to be explored more fully whilst still maintaining the linkages between the urban and rural community in the Southern region of the ACT.
36 Environment ACT ACT Water Report 2001–2002 (Revised)
Riparian Projects Undertaken by Community Catchment Groups
Sullivan's Creek Catchment Group Inc. (SCCG) constructed the ACT's first wetland to be retrofitted into an established suburb. The wetland, located adjacent to David Street in O'Connor (behind the O'Connor Shops) was built in September 2001. The development of this wetland involved the diversion of low flows from the O'Connor Stormwater Tributary into an excavated pond of approximately 0.4 hectares in size. The stormwater is detained in the pond and treated. Nutrient and bacterial pollutants will be reduced, with an expectation of improving the quality of the water by about 50%. The water is then diverted back into the O'Connor channel in a much healthier state. The wetland has been landscaped with over 55,000 native plants including water plants, grasses, shrubs and trees. SCCG volunteers undertook the planting of the wetland.
The wetland has received overwhelming support from the community and is performing very well. The construction of the wetland was funded predominantly by the private sector — CIC Pendon and Community Housing Canberra — who redeveloped the City Edge Apartments. The project was funded partly by the Natural Heritage Trust, which is a Federal Government environment fund. The ACT Government funded the new playground and has agreed to undertake the on-going maintenance of the wetland in partnership with the community.
Ginninderra Catchment Group has established a comprehensive water quality and monitoring program that includes: Participation in the Waterwatch program; storm Action Squad — a ‘rapid response team’ that tests turbidity during runoff events at 2 sites; and frogwatch — frog numbers and diversity are monitored by volunteers at 9 sites in Spring and Autumn.
In 2002 the willow removal project on Ginninderra Creek was completed. Since 1998, more than 10,000 willow stems have been poisoned, removed and chipped. There has been a significant increase in the creek’s discharge, and in the number and diversity of water birds using the creek. The Catchment Group has submitted an Envirofund application to control willow suckering, thus maintaining the outcomes of this highly successful project.
Control of weed infestations in the creek corridor continues to be a major focus for on-ground works and includes the manual and chemical control of weeds such as hawthorn, blackberry and Paterson’s Curse. Revegetation activities since 1998, have seen more than 8,000 native trees and shrubs planted in the Ginninderra Creek corridor with Landcare Groups maintain these plantings by weeding, watering and mulching.
Although still in its infancy, Southern ACT Catchment Group has undertaken a study of Yarralumla Creek below Cotter Road to assess management options for its restoration. The group is also investigating, and awaiting the tender outcomes of, options for the restoration of Tuggeranong Creek through the Tuggeranong Homestead site.
Riparian ACTion
The ACT Riparian Restoration Program 2001 is now underway in the ACT. Called ‘Riparian ACTion’, the project is a joint initiative of Greening Australia and Environment ACT with funds sourced from the Murray-Darling 2001 Program of the Natural Heritage Trust. Riparian ACTion seeks to target incentive funding to landholders and land managers to undertake erosion control measures and vegetation restoration within riparian zones along the Murrumbidgee River and its tributaries in the ACT.
Greening Australia field staff are assisting Environment ACT in delivering the program by providing a field officer to liaise with property owners and provide technical advice on riparian zone revegetation. The project also closely links with Greening Australia’s ‘Bidgee Banks’ project operating in the NSW Middle and Upper Murrumbidgee River Catchments. This project is delivering similar funding to landholders to provide for actions such as off-stream watering points, fencing of riparian vegetation and rehabilitation of degraded watercourses.
Considerable efforts were undertaken in the previous reporting period to target the funds to the areas of greatest need. An ACT wide analysis of stream condition over time was completed to inform
Environment ACT 37 ACT Water Report 2001–2002 (Revised)
decisions about funding. This approach used historical records, such as aerial photographs, to identify any changes in drainage networks. Many streams, channels and gullies in the ACT are still undergoing natural processes of change that need to be better understood. Similarly, much gully erosion is no longer active and under natural processes of revegetation and stabilisation.
In looking at the priorities for funding a number of factors are being considered by the community/government steering group for the project. Of importance are links to other initiatives being undertaken in the ACT to address the conservation of natural values in rural areas. For instance, the ACT’s Rural Conservation Fund, also supported by the Natural Heritage Trust, addresses the conservation of remnant native vegetation on rural properties. The joint delivery of these two projects by Greening Australia will achieve significant outcomes in addressing erosion and land degradation issues and nature conservation needs comprehensively across each landholding.
Riparian ACTion funding is now available to property owners to assist with fencing materials, earthworks, tubestock, direct seeding and ancillary measures. Funding is expected to be matched by applicants, either in-kind or with cash contributions.
Monitoring water quality improvements following on-ground works is an important aspect of Riparian ACTion. The monitoring work will be done in collaboration with the ACT Waterwatch Program that is well established in most sub-catchments of the ACT.
For more information contact: John Feint ACT NHT Coordinator Environment ACT Tel: 02 6207 5584 Fax: 02 6207 2244 Email: [email protected]
38 Environment ACT ACT Water Report 2001–2002 (Revised)
APPENDIX 1 – CHARTS ILLUSTRATING RIVER FLOW IN THREE CLIMATIC REGIONS
The charts below illustrate the river flow, from three different climatic regions. Within each chart is the mean monthly flow for the reporting year and the mean monthly flow for the ten year period 1992- 2002 for the sampling station.
Ginninderra Creek near Barton Highway
1.0 1992-2002 (smoothed) Actual 2001-2002
0.8 cs) n 0.6
0.4 ow (cumi Fl
0.2
0.0 Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Molonglo River at Burbong Bridge 2.0
1992-2002(smoothed) Actual 2001-2002 1.6
1.2
0.8 ow (cumecs) Fl
0.4
0.0 Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar
Gudgenby River at Tennent 5 1992-2001 (smoothed) Actual 2001-2002 4
3
2 ow (cumecs) Fl
1
0 Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar
Environment ACT 39 ACT Water Report 2001–2002 (Revised)
APPENDIX 2 – ASSESSMENT METHODOLOGY
The methods for determining whether a standard was exceeded and the presence and magnitude of a trend in the long term data are described below:
Comparisons with Standards
Some water quality indicators such as suspended solids, turbidity, total phosphorus and total nitrogen normally vary in direct proportion with streamflow. The following method has been used to compare current year levels of these indicators with past trends corrected for different flows.
Determining the proportion of time an indicator is predicted to exceed the standard is a three-step process.
The first step involves plotting all data records against the flow percentile at the time of sampling.
Long term Total Phosphorus
0.250
0.225
0.200
0.175
0.150 L 0.125 mg/ 0.100
0.075
0.050
0.025
0.000 100 95 90 85 80 75 70 65 60 55 50 45 40 35 30 25 20 15 10 5 0 Flow Percentile
The scatter plot shows a general trend that as flow increases (lower flow percentile number) the concentration of the indicator, in this case total phosphorus, increases.
When we fit a curve to this trend we can then see at what point the line crosses the water quality standard (step two). The curve may be logarithmic, exponential or linear.
Long term Total Phosphorus with Trend
0.250
0.225
0.200
0.175
0.150
0.125 mg/L 0.100
0.075
0.050
0.025
0.000 100 95 90 85 80 75 70 65 60 55 50 45 40 35 30 25 20 15 10 5 0 Flow Percentile
With this particular example, the line of best fit crosses the standard at a flow percentile of three. Generalising, we can say that for total phosphorus at this site, the standard is only exceeded when the flow gets above the third percentile, ie the flow that is exceeded only three percent of the time (very high flow).
40 Environment ACT ACT Water Report 2001–2002 (Revised)
The third step involves looking at the previous 12 months data and fitting a similar curve. The flow at which standards were exceeded for the indicator can again be determined by looking at where the line crosses the standard. In this example the line does not cross the standard so we would say that based on the samples taken during the period, the standard would not be exceeded at any part of the flow regime.
1998 - 99 Reporting period 0.12
0.11 Water Quality Standard 0.10
0.09
0.08
0.07
0.06
mg/L 0.05
0.04
0.03
0.02
0.01
0.00 100 95 90 85 80 75 70 65 60 55 50 45 40 35 30 25 20 15 10 5 0 Flow Percentile
Environment ACT 41 ACT Water Report 2001–2002 (Revised)
Long Term Trend
Trend analysis for flow dependent indicators was conducted by using multiple regression to relate concentration to the independent variables time, flow and seasonality.
The criteria for determining a significant long term trend are as follows:
• the coefficient for time in the regression must be significant; and • the overall significance of the regression must be < 0.05.
If the coefficients for flow, seasonality or both are not significant, these variables are removed from the regression.
The value for R2 is also important when interpreting the relationship and is used as an indication of how well the model is predicting the concentration. As R2 approaches 1 the trend has a higher correlation with the data points. In the sites monitored the R2 is usually below 0.5, as there is a relatively large variation.
If a trend is identified it takes the following form:
C = BDateXDate + BFlowXFlow + BSeasXSeas + I
Where: C = Concentration of parameter I = Y Intercept BDate = B weight for Date BFlow = B weight for Flow BSeas = B weight for Seasonality XDate = Variable Date XFlow = Variable Flow XSeas = Variable Seasonality
The median for flow and seasonality is then substituted into the equation to result in a 2 dimensional trend of concentration verses time, which is represented on the scatter plot as shown in Appendix 4. For further information on the method, please contact Environment ACT.
42 Environment ACT ACT Water Report 2001–2002 (Revised)
APPENDIX 3 – BIOLOGICAL MONITORING RESULTS
The Macro invertebrate monitoring results for the Spring 2001 and Autumn 2002 sessions are as follows:
O/E Site Band Site Location Autumn Spring
2002 2001 Test Sites 20 Smith Crossing A X 53 Halls Crossing B A 58 Downstream of Lake Tuggeranong B C 64 Latham B D 189 Cotter Road bridge C D 195 Baldwin Drive bridge B C 196 Downstream of Lake Ginninderra B D 235 Below Queanbeyan cemetery B C 242 Sutton Road bridge B B 246 Hindmarsh Drive bridge B C Reference Sites 10 Murray's Corner B A 15 Paddys River Road A A 40 Angle Crossing B A
where: X – Above reference A - Equivalent to reference sites B – Slightly impaired C – Moderately impaired D – Severally impaired
Environment ACT 43 ACT Water Report 2001–2002 (Revised)
APPENDIX 4 – RESULTS FROM SAMPLING SITES
This section contains the scatter plots of data for all sites sampled and the indicators discussed in this report.
44 Environment ACT ACT Water Report 2001–2002 (Revised)
204 - Murrumbidgee River at Halls Crossing
Turbidity Total Phosphorus Total Nitrogen Suspended Solids 100 0.24 16 240
trend trend 0.20 80 12 180
0.16 60 L L L / 0.12 / 8 / 120 NTU mg mg mg 40 0.08
4 60 20 0.04
0 0.00 0 0 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 May-1990 Jan-1993 Oct-1995 Jul-1998 Apr-2001 Jan-2004 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002
pH Ammonia Faecal Coliforms Dissolved Oxygen 10.0 2.0 1000 15
trend 900 9.5 1.6 800 13 9.0 700 8.5
1.2 L 600 11 L L / 8.0 / 500 PH mg mg 0.8 400 9 7.5 cfu/100 m 300 7.0 0.4 200 7 6.5 100
6.0 0.0 0 5 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Dec-1985 Dec-1988 Dec-1991 Jan-1995 Jan-1998 Jan-2001 Jan-2004 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002
Conductivity Chlorophyll 'a' 600 90
trend 80 500 70
400 60
50 300
ug/L 40 us/cm
200 30
20 100 10
0 0 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002
Environment ACT 45 ACT Water Report 2001–2002 (Revised)
207 - Murrumbidgee River at Uriarra Crossing
Turbidity Total Phosphorus Total Nitrogen 100 0.4 1.8 trend trend 1.6
1.4 75 0.3 1.2
1.0
U 50 0.2 0.8 NT mg/L mg/L 0.6 25 0.1 0.4
0.2
0 0.0 0.0 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 May-1990 Jan-1993 Oct-1995 Jul-1998 Apr-2001 Jan-2004
Total Dissolved Solids Suspended Solids pH 160 200 9.5 trend 140 175 9.0 120 150 8.5 100 125 8.0 80 100
PH 7.5 mg/L 60 mg/L 75 7.0 40 50
20 25 6.5
0 0 6.0 Oct-1995 Dec-1996 Jan-1998 Feb-1999 Mar-2000 Apr-2001 May-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002
Ammonia Faecal Coliforms 0.06 3000 trend
0.05 2500
0.04 2000
0.03 1500 mg/L 0.02 1000 cfu/100 mL
0.01 500
0.00 0 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Nov-1984 Nov-1987 Nov-1990 Nov-1993 Dec-1996 Dec-1999 Dec-2002
46 Environment ACT ACT Water Report 2001–2002 (Revised)
209 - Murrumbidgee River at Kambah Pool
Turbidity Total Phosphorus Total Nitrogen Suspended Solids 80 0.18 1.2 80
trend trend 70 0.16 70 1.0 0.14 60 60
0.12 0.8 50 50 0.10 L L L 40 / / 0.6 / 40
NTU 0.08 mg mg mg 30 30 0.06 0.4
20 20 0.04 0.2 10 0.02 10
0 0.00 0.0 0 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 May-1990 Jan-1993 Oct-1995 Jul-1998 Apr-2001 Jan-2004 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002
pH Ammonia Faecal Coliforms Dissolved Oxygen 10.0 0.07 800 15
14 9.5 0.06 700
13 9.0 600 0.05 12 8.5 500 L 0.04 11 L L / 8.0 / 400
PH 10 mg mg 0.03 7.5 300 cfu/100 m 9 0.02 7.0 200 8
0.01 6.5 100 7
6.0 0.00 0 6 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Nov-1984 Nov-1987 Nov-1990 Nov-1993 Dec-1996 Dec-1999 Dec-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002
Conductivity Chlorophyll 'a' 240 25
trend trend
200 20
160 15
120 ug/L us/cm 10 80
5 40
0 0 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002
Environment ACT 47 ACT Water Report 2001–2002 (Revised)
213 - Murrumbidgee River at Angle Crossing
Turbidity Total Phosphorus Total Nitrogen Suspended Solids 60 0.16 0.8 90
trend trend trend 0.14 0.7 80 50 70 0.12 0.6
40 60 0.10 0.5 50 L L L 30 / 0.08 / 0.4 /
NTU 40 mg mg mg 0.06 0.3 20 30
0.04 0.2 20 10 0.02 0.1 10
0 0.00 0.0 0 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002
pH Ammonia Faecal Coliforms Dissolved Oxygen 9.6 0.05 400 14
trend 9.2 350 13 0.04 8.8 300 12
8.4 250 11
0.03 L L L / 8.0 / 200 10 PH mg mg 0.02 7.6 150 9 cfu/100 m
7.2 100 8 0.01 6.8 50 7
6.4 0.00 0 6 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Nov-1984 Nov-1987 Nov-1990 Nov-1993 Dec-1996 Dec-1999 Dec-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002
Conductivity Cholorophyll 'a' 240 16
trend trend 14 200
12
160 10
120 8 ug/L us/cm 6 80
4
40 2
0 0 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002
48 Environment ACT ACT Water Report 2001–2002 (Revised)
224 - Murrumbidgee River at ACT Border
Turbidity Total Phosphorus Total Nitrogen 80 0.20 20 trend trend trend 70 0.18 18 0.16 16 60 0.14 14 50 0.12 12
U 40 0.10 10 NT 30 mg/L 0.08 mg/L 8 0.06 6 20 0.04 4 10 0.02 2 0 0.00 0 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 May-1990 Jan-1993 Oct-1995 Jul-1998 Apr-2001 Jan-2004
Total Dissolved Solids Suspended Solids pH 400 9.2 140 trend trend 350 8.8 120 8.4 300 100 8.0 250 80 7.6 200
PH 7.2 mg/L 150 mg/L 60 6.8 40 100 6.4
50 20 6.0
0 0 5.6 Jun-1997 Apr-1998 Feb-1999 Dec-1999 Oct-2000 Jul-2001 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002
Ammonia Faecal Coliforms 2.5 4000 trend 3500 2.0 3000
1.5 2500 2000
mg/L 1.0 1500 cfu/100 mL 1000 0.5 500
0.0 0 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Nov-1984 Nov-1987 Nov-1990 Nov-1993 Dec-1996 Dec-1999 Dec-2002
Environment ACT 49 ACT Water Report 2001–2002 (Revised)
248 - Lake Tuggeranong at Kambah Wetland
Turbidity Total Phosphorus Total Nitrogen Suspended Solids 140 0.24 2.0 trend trend 60 trend 120 1.8 0.20 1.6 50 100
0.16 1.4 40 80 1.2 U L L L / 0.12 / NT
mg/ 30 60 1.0 mg mg
0.08 0.8 40 20
0.6
20 0.04 10 0.4
0 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 0.00 0.2 0 Aug-1987 May-1990 Jan-1993 Oct-1995 Jul-1998 Apr-2001 Jan-2004 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Dec-1988 Dec-1991 Jan-1995 Jan-1998 Jan-2001 Jan-2004
pH Ammonia Faecal Coliforms Dissolved Oxygen 10.5 20000 14
0.24 10.0 trend trend 12 16000 9.5 0.20
9.0 10
0.16 12000 8.5 L L 8 PH 100 mL mg/ mg/ 0.12
8.0 u/
cf 8000
7.5 6 0.08
7.0 4000 0.04 4 6.5
6.0 0.00 0 2 Aug-1987 May-1990 Jan-1993 Oct-1995 Jul-1998 Apr-2001 Jan-2004 Aug-1987 May-1990 Jan-1993 Oct-1995 Jul-1998 Apr-2001 Jan-2004 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Oct-1989 Jul-1992 Apr-1995 Jan-1998 Oct-2000 Jun-2003
Conductivity Chlorophyll'a' 400 35
trend 360 30
320 25
280 20
240 L ug/ 15 us/cm 200
10 160
5 120
80 0 Dec-1988 Dec-1991 Jan-1995 Jan-1998 Jan-2001 Jan-2004 Aug-1987 May-1990 Jan-1993 Oct-1995 Jul-1998 Apr-2001 Jan-2004
50 Environment ACT ACT Water Report 2001–2002 (Revised)
249 - Lake Tuggeranong at Dam Wall
Turbidity Total Phosphorus Total Nitrogen Suspended Solids 140 0.24 2.0 70
trend trend 1.8 120 60 0.20 1.6 100 50 0.16 1.4
80 1.2 40 L L L / 0.12 / /
NTU 1.0 60 mg mg mg 30
0.08 0.8 40 20 0.6 0.04 20 10 0.4
0 0.00 0.2 0 May-1990 Jan-1993 Oct-1995 Jul-1998 Apr-2001 Jan-2004 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 May-1990 Jan-1993 Oct-1995 Jul-1998 Apr-2001 Jan-2004 May-1990 Jan-1993 Oct-1995 Jul-1998 Apr-2001 Jan-2004
Ammonia pH Faecal Coliforms Dissolved Oxygen 0.20 9.2 5000 12
4500 8.8 0.16 4000 10
8.4 3500
0.12 L 3000 8 8.0 L L / / 2500 PH mg mg 7.6 0.08 2000 6 cfu/100 m
7.2 1500
0.04 1000 4 6.8 500
0.00 6.4 0 2 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 May-1990 Jan-1993 Oct-1995 Jul-1998 Apr-2001 Jan-2004
Conductivity Chlorophyll 'a' 380 25
trend 340 20
300
15 260 ug/L
us/cm 220 10
180
5 140
100 0 May-1990 Jan-1993 Oct-1995 Jul-1998 Apr-2001 Jan-2004 May-1990 Jan-1993 Oct-1995 Jul-1998 Apr-2001 Jan-2004
Environment ACT 51 ACT Water Report 2001–2002 (Revised)
270 - Point Hut Pond
Turbidity Total Phosphorus Total Nitrogen Suspended Solids 350 0.35 3.2 280
trend 300 0.30 2.8 240
250 0.25 2.4 200
200 0.20 2.0 160 L L L / / / NTU 150 mg 0.15 mg 1.6 mg 120
100 0.10 1.2 80
50 0.05 0.8 40
0 0.00 0.4 0 Jul-1992 Jun-1994 May-1996 Apr-1998 Mar-2000 Feb-2002 Oct-1992 Sep-1994 Aug-1996 Jul-1998 Jun-2000 May-2002 Jul-1992 Jun-1994 May-1996 Apr-1998 Mar-2000 Feb-2002 Jul-1992 Jun-1994 May-1996 Apr-1998 Mar-2000 Feb-2002
pH Ammonia Faecal Coliforms Dissolved Oxygen 9.4 0.30 700 13
trend 12 9.0 600 0.24 11 8.6 500 10 0.18 8.2 L 400 9 L L / /
PH 7.8 8 mg mg 0.12 300 cfu/100 m 7.4 7 200 0.06 6 7.0 100 5 6.6 0.00 Apr-1992 Jul-1995 Nov-1998 Feb-2002 Apr-1992 Jul-1995 Nov-1998 Feb-2002 0 4 Nov-1993 Mar-1997 Jun-2000 Nov-1993 Mar-1997 Jun-2000 Nov-1993 Jul-1995 Mar-1997 Nov-1998 Jun-2000 Feb-2002 Oct-2003 Jul-1992 Mar-1994 Oct-1995 Jun-1997 Feb-1999 Oct-2000 May-2002
Conductivity Cholorophyll 'a' 400 80
360 70
60 320
50 280 40 ug/L
us/cm 240 30
200 20
160 10
120 0 Dec-1991 Nov-1993 Oct-1995 Sep-1997 Aug-1999 Jul-2001 Jun-2003 Jul-1992 Mar-1994 Oct-1995 Jun-1997 Feb-1999 Oct-2000 May-2002
52 Environment ACT ACT Water Report 2001–2002 (Revised)
301 - Ginninderra Creek at Parkwood
Turbidity Total Phosphorus Total Nitrogen Suspended Solids 80 0.20 2.0 80
trend trend 70 70 0.16 1.6 60 60
50 50 0.12 1.2 L L L 40 / / / 40 NTU mg mg mg 0.08 0.8 30 30
20 20 0.04 0.4 10 10
0 0.00 0.0 0 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002
pH Ammonia Faecal Coliforms Dissolved Oxygen 9.0 0.14 10000 15
9000 14 0.12 8.5 8000 13 0.10 7000 12
8.0 L 6000 0.08 11 L L / / 5000
PH 10 mg mg 0.06 7.5 4000 cfu/100 m 9 0.04 3000 8 7.0 2000 0.02 1000 7
6.5 0.00 0 6 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Nov-1984 Nov-1987 Nov-1990 Nov-1993 Dec-1996 Dec-1999 Dec-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002
Conductivity Cholorophyll 'a' 800 28
trend 700 24
600 20
500 16 400 ug/L
us/cm 12 300
8 200
100 4
0 0 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002
Environment ACT 53 ACT Water Report 2001–2002 (Revised)
318 - Lake Ginninderra West
Turbidity Total Phosphorus Total Nitrogen Suspended Solids 0.5 1.8 80
60 trend trend trend 1.6 70 0.4 50 1.4 60
1.2 50 40 0.3 L L L / / 1.0 / 40 30 NTU mg mg mg 0.2 0.8 30 20 0.6 20 0.1 10 0.4 10
0 0.0 0.2 0 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 May-1990 Jan-1993 Oct-1995 Jul-1998 Apr-2001 Jan-2004 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002
pH Ammonia Faecal Coliforms Dissolved Oxygen 9.2 0.5 140 13
trend trend trend 120 8.8 11 0.4
100 8.4 9
0.3 L 80 L L / 8.0 / 7 PH mg mg 60 0.2 7.6 cfu/100 m 5 40
0.1 7.2 3 20
6.8 0.0 0 1 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Nov-1984 Nov-1987 Nov-1990 Nov-1993 Dec-1996 Dec-1999 Dec-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002
Conductivity Chlorophyll 'a' 420 35
trend 380 30
340 25
300 20 260 ug/L
us/cm 15 220
10 180
140 5
100 0 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002
54 Environment ACT ACT Water Report 2001–2002 (Revised)
321 - Lake Ginninderra at East Arm
Turbidity Total Nitrogen Total Phosphorus Suspended Solids 120 0.40
5 trend 100 trend 0.35 100
0.30 4 80 80 0.25
3 60 L L L 60 / / 0.20 / NTU mg mg mg
2 0.15 40 40
0.10
20 1 20 0.05
0 0 0.00 0 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 May-1990 Jan-1993 Oct-1995 Jul-1998 Apr-2001 Jan-2004 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002
pH Ammonia Faecal Coliforms Dissolved Oxygen 9.4 3000 14
trend trend 13 trend 9.0 2500 12
11 8.6 2000 10
8.2 L 9 L L 1500 / / 8 PH mg 7.8 mg 7
cfu/100 m 1000 6 7.4 5 500 4 7.0 3 0 6.6 Nov-1984 May-1990 Oct-1995 Apr-2001 2 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Aug-1987 Jan-1993 Jul-1998 Jan-2004 May-1990 Jan-1993 Oct-1995 Jul-1998 Apr-2001 Jan-2004
Conductivity Chlorophyll 'a' 420 50
trend 380 40
340
30 300 ug/L
us/cm 260 20
220
10 180
140 0 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002
Environment ACT 55 ACT Water Report 2001–2002 (Revised)
346 - Gungahlin Pond
Turbidity Total Phosphorus Total Nitrogen Suspended Solids 0.20 2.6 140
240 trend trend 120 2.2 0.16 200 100 1.8 160 0.12 80 L L L / / 1.4 / 120 NTU mg mg mg 60 0.08 1.0 80 40
0.04 0.6 40 20
0 0.00 0.2 0 Aug-1993 Apr-1995 Dec-1996 Jul-1998 Mar-2000 Nov-2001 Jun-2003 Aug-1993 Apr-1995 Dec-1996 Jul-1998 Mar-2000 Nov-2001 Jun-2003 Aug-1993 Apr-1995 Dec-1996 Jul-1998 Mar-2000 Nov-2001 Jun-2003 Aug-1993 Apr-1995 Dec-1996 Jul-1998 Mar-2000 Nov-2001 Jun-2003
pH Ammonia Faecal Coliforms Dissolved Oxygen 9.6 0.35 13
100 0.30 9.0 11
0.25 80
8.4 L 9 0.20 60 L L / / PH mg mg 0.15 7.8 7
cfu/100 m 40 0.10
7.2 20 5 0.05
6.6 0.00 0 3 Aug-1993 Apr-1995 Dec-1996 Jul-1998 Mar-2000 Nov-2001 Jun-2003 Aug-1993 Apr-1995 Dec-1996 Jul-1998 Mar-2000 Nov-2001 Jun-2003 Aug-1993 Apr-1995 Dec-1996 Jul-1998 Mar-2000 Nov-2001 Jun-2003 Aug-1993 Apr-1995 Dec-1996 Jul-1998 Mar-2000 Nov-2001 Jun-2003
Conductivity Chlorophyll 'a' 540 24
trend 480 20
420 16
360 12 ug/L us/cm
300 8
240 4
180 0 Aug-1993 Apr-1995 Dec-1996 Jul-1998 Mar-2000 Nov-2001 Jun-2003 Aug-1993 Apr-1995 Dec-1996 Jul-1998 Mar-2000 Nov-2001 Jun-2003
56 Environment ACT ACT Water Report 2001–2002 (Revised)
401 - Molonglo River at Sturt Island
Total Phosphorus Total Nitrogen Total Dissolved Solids 0.5 28 500 trend trend 24 0.4 400 20
0.3 300 16
12 mg/L mg/L mg/L 0.2 200
8 0.1 100 4
0.0 0 0 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Sep-1997 Nov-1998 Dec-1999 Jan-2001 Feb-2002
Suspended Solids pH Ammonia 140 10 8 trend trend 120 7 9 6 100 5 80 8 4
60 PH mg/L mg/L 3 40 7 2
20 1
0 6 0 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002
Faecal Coliforms 4000
3500
3000
2500
2000
1500 cfu/100 mL 1000
500
0 Nov-1984 Nov-1987 Nov-1990 Nov-1993 Dec-1996 Dec-1999 Dec-2002
Environment ACT 57 ACT Water Report 2001–2002 (Revised)
407 - Molonglo River at Copping Crossing
Turbidity Total Phosphorus Total Nitrogen 90 1.6 trend trend 1.4 75 0.24 1.2 60 0.18 1.0
U 45 0.8 0.12 NT mg/L mg/L 0.6 30 0.4 0.06 15 0.2
0 0.00 0.0 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 May-1990 May-1993 May-1996 May-1999 May-2002
Total Dissolved Solids Suspended Solids pH 300 140 9.0 trend trend 250 120 8.5
100 200 8.0 80 150 7.5
60 PH mg/L mg/L 100 7.0 40
50 20 6.5
0 0 6.0 Mar-1997 Jan-1998 Nov-1998 Aug-1999 Jun-2000 Apr-2001 Feb-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002
Ammonia Faecal Coliforms 0.10 4000 trend 3500 0.08 3000
0.06 2500 2000
mg/L 0.04 1500 cfu/100 mL 1000 0.02 500
0.00 0 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Nov-1984 Nov-1987 Nov-1990 Nov-1993 Dec-1996 Dec-1999 Dec-2002
58 Environment ACT ACT Water Report 2001–2002 (Revised)
601 - Molonglo River at Dairy Flat
Turbidity Total Phosphorus Total Nitrogen 60 0.20 3.4 trend trend 3.0 50 0.16 2.6 40 0.12 2.2
U 30 1.8 NT mg/L 0.08 mg/L 1.4 20 1.0 0.04 10 0.6
0 0.00 0.2 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002
Suspended Solids pH Ammonia 9.5 0.14 trend 80 9.0 0.12
0.10 60 8.5 0.08 8.0
40 PH 0.06 mg/L mg/L 7.5 0.04 20 7.0 0.02
0 6.5 0.00 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002
Faecal Coliforms Dissolved Oxygen Conductivity 1200 14 500
1000 12 400
800 10 300 600 8 mg/L mg/L
us/cm 200 400 6
100 200 4
0 2 0 Nov-1984 Nov-1987 Nov-1990 Nov-1993 Dec-1996 Dec-1999 Dec-2002 Oct-1995 Mar-1997 Jul-1998 Dec-1999 Apr-2001 Sep-2002 Jan-2004 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002
Environment ACT 59 ACT Water Report 2001–2002 (Revised)
608 - Molonglo River at Yass Road
Turbidity Total Phosphorus Total Nitrogen Suspended Solids 100 0.14 1.4 70
0.12 1.2 60 80
0.10 1.0 50
60 0.08 0.8 40 L L L / / / NTU mg 0.06 mg 0.6 mg 30 40
0.04 0.4 20
20 0.02 0.2 10
0 0.00 0.0 0 Mar-1994 Jul-1995 Dec-1996 Apr-1998 Aug-1999 Jan-2001 May-2002 Mar-1994 Jul-1995 Dec-1996 Apr-1998 Aug-1999 Jan-2001 May-2002 Mar-1994 Jul-1995 Dec-1996 Apr-1998 Aug-1999 Jan-2001 May-2002 Mar-1994 Jul-1995 Dec-1996 Apr-1998 Aug-1999 Jan-2001 May-2002
pH Ammonia Faecal Coliforms Dissolved Oxygen 8.5 0.040 4500 16
0.035 14 3750
8.0 0.030 12
3000 0.025 10 L L L / 7.5 / 0.020 2250 8 PH mg mg 0.015 6 cfu/100 m 1500
7.0 0.010 4
750 0.005 2
6.5 0.000 0 0 Mar-1994 Jul-1995 Dec-1996 Apr-1998 Aug-1999 Jan-2001 May-2002 Mar-1994 Jul-1995 Dec-1996 Apr-1998 Aug-1999 Jan-2001 May-2002 Mar-1994 Jul-1995 Dec-1996 Apr-1998 Aug-1999 Jan-2001 May-2002 Mar-1994 Jul-1995 Dec-1996 Apr-1998 Aug-1999 Jan-2001 May-2002
Conductivity chlorophyll 'a' 800 18
trend trend
15
600
12
400 9 ug/L us/cm
6
200
3
0 0 Mar-1994 Jul-1995 Dec-1996 Apr-1998 Aug-1999 Jan-2001 May-2002 Mar-1994 Jul-1995 Dec-1996 Apr-1998 Aug-1999 Jan-2001 May-2002
60 Environment ACT ACT Water Report 2001–2002 (Revised)
769 - Queanbeyan River at ACT Border
Turbidity Total Phosphorus Total Nitrogen Suspended Solids 40 0.08 1.4 50
35 0.07 1.2 40 30 0.06
1.0 25 0.05 30 L L L 20 / 0.04 / 0.8 / NTU mg mg mg 20 15 0.03 0.6
10 0.02 10 0.4 5 0.01
0 0.00 0.2 0 Mar-1994 Jul-1995 Dec-1996 Apr-1998 Aug-1999 Jan-2001 May-2002 Mar-1994 Jul-1995 Dec-1996 Apr-1998 Aug-1999 Jan-2001 May-2002 Mar-1994 Jul-1995 Dec-1996 Apr-1998 Aug-1999 Jan-2001 May-2002 Mar-1994 Jul-1995 Dec-1996 Apr-1998 Aug-1999 Jan-2001 May-2002
pH Ammonia Faecal Coliforms Dissolved Oxygen 8.5 0.035 6000 13
0.030 5000 11 8.0 0.025 4000
L 9 0.020 L L / 7.5 / 3000 PH mg mg 0.015 7 cfu/100 m 2000 0.010 7.0 5 1000 0.005
6.5 0.000 0 3 Mar-1994 Jul-1995 Dec-1996 Apr-1998 Aug-1999 Jan-2001 May-2002 Mar-1994 Jul-1995 Dec-1996 Apr-1998 Aug-1999 Jan-2001 May-2002 Mar-1994 Jul-1995 Dec-1996 Apr-1998 Aug-1999 Jan-2001 May-2002 Mar-1994 Jul-1995 Dec-1996 Apr-1998 Aug-1999 Jan-2001 May-2002
Conductivity Chlorophyll 'a' 400 40
350 35
300 30
250 25
200 20 ug/L us/cm 150 15
100 10
50 5
0 0 Mar-1994 Jul-1995 Dec-1996 Apr-1998 Aug-1999 Jan-2001 May-2002 Mar-1994 Jul-1995 Dec-1996 Apr-1998 Aug-1999 Jan-2001 May-2002
Environment ACT 61 ACT Water Report 2001–2002 (Revised)
842 - Paddys River at Riverlea
Turbidity Total Phosphorus Total Nitrogen Suspended Solids 80 0.16 1.6 80
70 0.14 1.4
60 0.12 1.2 60
50 0.10 1.0 L L L 40 / 0.08 / 0.8 / 40 NTU mg mg mg 30 0.06 0.6
20 0.04 0.4 20
10 0.02 0.2
0 0.00 0.0 0 Jun-1997 Jul-1998 Aug-1999 Oct-2000 Nov-2001 Dec-2002 Dec-1996 Jan-1998 Feb-1999 Mar-2000 Apr-2001 May-2002 Dec-1996 Jan-1998 Feb-1999 Mar-2000 Apr-2001 May-2002 Dec-1996 Jan-1998 Feb-1999 Mar-2000 Apr-2001 May-2002
pH Ammonia Faecal Coliforms Dissolved Oxygen 8.5 0.020 3000 15
trend 14 8.0 0.016 2400
13
7.5 0.012 L 1800 12 L L / / PH mg mg 11 7.0 0.008 1200 cfu/100 m
10
6.5 0.004 600 9
6.0 0.000 0 8 Mar-1997 Apr-1998 May-1999 Jun-2000 Jul-2001 Sep-2002 Dec-1996 Jan-1998 Feb-1999 Mar-2000 Apr-2001 May-2002 Dec-1996 Jan-1998 Feb-1999 Mar-2000 Apr-2001 May-2002 Dec-1996 Jan-1998 Feb-1999 Mar-2000 Apr-2001 May-2002
Conductivity chlorophylla 'a' 300 8
7
240 6
5 180
4 ug/L us/cm 120 3
2 60
1
0 0 Dec-1996 Jan-1998 Feb-1999 Mar-2000 Apr-2001 May-2002 Dec-1996 Jan-1998 Feb-1999 Mar-2000 Apr-2001 May-2002
62 Environment ACT ACT Water Report 2001–2002 (Revised)
901 - Gudgenby River at Tennent
Turbidity Total Phosphor us Total Nitrogen Suspended Sol ids 100 0.24 1.4 60
trend trend 1.2 0.20 50 80
1.0 0.16 40 60 0.8 L L L U 0.12 30 NT mg/ mg/ mg/ 0.6 40 0.08 20 0.4
20 0.04 10 0.2
0 0.00 0.0 0 May-1990 Jan-1993 Oct-1995 Jul-1998 Apr-2001 Jan-2004 May-1990 Jan-1993 Oct-1995 Jul-1998 Apr-2001 Jan-2004 May-1990 Jan-1993 Oct-1995 Jul-1998 Apr-2001 Jan-2004 Jan-1993 Oct-1995 Jul-1998 Apr-2001 Jan-2004
pH Ammoni a Faecal Coliforms Dissolved Oxygen 9.0 0.16 2400 14
2000 8.5 12 0.12
1600 8.0 10 L L 0.08 1200 PH 100 mL mg/ mg/
7.5 u/ 8 f c 800
0.04 7.0 6 400
6.5 0.00 0 4 May-1990 Jan-1993 Oct-1995 Jul-1998 Apr-2001 Jan-2004 May-1990 Jan-1993 Oct-1995 Jul-1998 Apr-2001 Jan-2004 Dec-1988 Sep-1991 Jun-1994 Mar-1997 Dec-1999 Sep-2002 May-1990 Jan-1993 Oct-1995 Jul-1998 Apr-2001 Jan-2004
Conductivity Cholorophyll 'a' 400 24
trend trend 350 20
300
16 250 m L
c 200 12 / ug/ us 150 8
100
4 50
0 0 May-1990 Jan-1993 Oct-1995 Jul-1998 Apr-2001 Jan-2004 May-1990 Jan-1993 Oct-1995 Jul-1998 Apr-2001 Jan-2004
Environment ACT 63