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WATER AND WASTE COMMITTEE 1 21 OCTOBER 2009

WATER SUPPLY AND DEMAND, /MOSSMAN WATER SUPPLY SCHEME

Eric Zesers : 24/22/212-03: #2339446

RECOMMENDATION:

That Council notes the report.

INTRODUCTION:

The water supply for Mossman, Port Douglas, , Mowbray, Newell Beach, Cooya Beach and Cassowary is sourced directly from Rex Creek which is a tributary of the Mossman River. Due to unprecedented dry conditions, water levels in Rex Creek have fallen to levels that have required the following actions be undertaken:

• Implementation of Level 1 Water restrictions for Port Douglas, Mossman, Craiglie, Mowbray, Newell Beach, Cooya Beach and Cassowary, on 2 October 2009. • Progression to Level 2 Water Restrictions on 12 October 2009. • Application to the Department of Environment and Resource Management (DERM) for a temporary emergency extraction permit for water from the Mossman River. • Application to DERM for an internal review of the original decision relating to the licence limit to extract water from Rex Creek to supply water to Port Douglas and Mossman. • Application to DERM to exceed license limits for water extraction during periods of low flow.

This report provides details of the above matters.

BACKGROUND:

The winter of 2009 has seen the lowest winter rainfall on record at the Low Isles Light House – 25.7 mm (average is 136.4 mm) and at the Airport – 17.2 mm (average is 102mm). As a result of the unprecedented dry conditions, run of river water supplies such as Rex Creek can also be expected to reach record lows or potentially could dry up completely. This has necessitated the introduction of water restrictions and plans to implement emergency water supplies as a contingency if consumption cannot be reduced to sustainable levels and/or it is not possible to extract sufficient water from the existing intake on Rex Creek.

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Water Demand

Permanent Water Conservation Measures have been in place in Division 10 since May 2008. However, water demand has increased steadily since February 2009 primarily due to the extended dry period.

Cairns Regional Council 2009 Water Production Port Douglas, Mossman &

500.00 450.00 400.00 350.00 300.00 Port Douglas / Mossman 250.00 Whyanbeel 200.00 Total Production

Production in ML in Production 150.00 100.00 50.00 0.00 l r i e y e uary ary pr Jul b n u A May Jun m br March August ctober Ja e te O cember F ep e S NovemberD Months

Daily water production since 1 September has exceeded 16 ML/day at an extraction rate of 185 litres per second. Daily per person consumption has been up to an estimated 1500 – 1600 litres per person per day, based on a serviced population of 10,000 people. Daily extractions based on water treatment plant production figures are shown in the following graph

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Mossman Treatment Plant - Daily plant production

Mossman Treatment Plant Production

18

16.8 16.3 16 16.1 15.2 15.3 15.0 15.0 14.4 14.5 14.5 14.4 14.6 14.1 14 13.7 13.9 13.9 13.2 13.2 12.8 12.3 12 11.9 12.1 12.1 11.5

10 Stage 1 restrictions Pressure to Mossman

ML/day 8 introduced reduced by 10%. Flow to parts of Port 6 Douglas reduced 5%. Stage 2 restrictions target Stage 2 restrictions 4 introduced

2

0

9 9 9 9 9 9 9 9 9 9 9 9 9 0 0 0 0 0 0 0 09 0 0 0 0 0 0 009 0 0 0 0 009 0 0 0 0 0 0 0 0 0 2 /2 /2009 2 /2 /2 /2009 2 /2 /2 /2 /20 /2009 2 /2 /2 9 9 9 9 0/2 0 0 0/2 0 0 0 /09/ 0 /09/ 0 /09/2009/0 /09/ 0 /10/2009 1 1 /10/2009 /1 /10/2009 1 /1 /10/ 1 /10/2009/1 1 4 6 7 9 1 2/ 3/ 4 5/10/2 6 7 8/ 9 1 3 4 2 22/ 23/09 2 25/ 2 2 28/09 2 30/ 10/10 1 12/ 1 1

Rex Creek Flows

During extended dry periods water flows in Rex Creek can fall to levels whereby there is insufficient water flowing into the intake to meet demands. Councils Drought Management Plan states that the trigger for level 1 water restrictions is when Rex Creek requires sandbagging to direct flows into the intake. Sand bags have been in place since September 10 2009. It should be noted that environmental flows have been allowed to pass beyond the water intake at this flow level.

Flow volumes are estimated from taking a water depth reading and extrapolating using a formulae to calculate discharge levels. The recorded water level in Rex Creek for the last 12 months is shown on the following graph. Data does not exist for the period prior to this. The second graph shows the water level in Rex Creek since May 2009 and illustrates the decline in water level during that period.

It should be noted that the flow is an estimate only and the level of accuracy is influenced by two factors. Firstly, the formulae used to calculate the flow is based on actual flow readings taken at different water depths. The degree of accuracy for this formulae is dependent on a range of factors and not be 100% accurate.

Secondly, when the creek is sandbagged, the actual water level is made deeper in the pool at the intake to ensure that enough flow enters the intake. The flow volume is therefore not accurately reflected by the water depth when sandbagging occurs.

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Flow levels in Rex Creek at the water intake

Rex Creek Stream Gauging

2.500

2.000

1.500

1.000

0.500

Recorded Water Level Height (m) Height Level Water Recorded 0.000 8/01/2009 5/02/2009 5/03/2009 2/04/2009 9/07/2009 6/08/2009 3/09/2009 1/10/2009 30/10/2008 13/11/2008 27/11/2008 11/12/2008 25/12/2008 22/01/2009 19/02/2009 19/03/2009 16/04/2009 30/04/2009 14/05/2009 28/05/2009 11/06/2009 25/06/2009 23/07/2009 20/08/2009 17/09/2009 Date

Height (m)

Rex Creek Stream Gauging - May to October

1.000

0.900

0.800 Sandbagging commenced 24/7/09 0.700

0.600

0.500

0.400

0.300

0.200 REcorded Water Level Height (m) 0.100

0.000 1/05/2009 8/05/2009 5/06/2009 3/07/2009 7/08/2009 4/09/2009 15/05/2009 22/05/2009 29/05/2009 12/06/2009 19/06/2009 26/06/2009 10/07/2009 17/07/2009 24/07/2009 31/07/2009 14/08/2009 21/08/2009 28/08/2009 11/09/2009

On Tuesday 13 October the sandbags were removed to allow an accurate reading of flow depth to be taken. At that time the flow level was estimated to be below 200 litres per second.

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Of concern is the timing of when flow levels increased in 2008. That did not occur until mid December following an estimated 138mm of rainfall over the winter period. If the same pattern occurs this year the concern is that Rex Creek will be close to drying up based on current trends.

Water Extraction Licence

The former Douglas Shire Council had an Order in Council to extract 513 ML/year from Rex Creek for water supply. The current annual extraction rate is approximately 3,700 ML/year.

An application was made to DERM on September 25 2008 to increase the extraction limit to reflect current and future demand for water. The application sought to increase the volume of water taken to 5,200 ML per annum at an extraction rate of 200 litres per second. An information notice for the licence application was received from DERM on August 20 2009. The notice advised an approved extraction of 4,800 ML per annum at a maximum rate of 170 litres per second. With a reducing sliding scale as the flow in the creek falls below 300 litres per second as shown in the following table.

Water extraction schedule from Rex Creek water license

Scheduled for Extraction - Rex Creek Maximum Extraction Flow Rex Creek Flow Rate Rate Litres per second Litres per second <40 0 41-60 20 61-80 30 81-100 40 101-120 50 121-140 60 141-160 70 161-200 80 201-250 120 251-300 150 >300 170

Water Restrictions

Level 1 water restrictions were introduced in the affected areas from Friday October 2. Restrictions are introduced in line with the Cairns Regional Council Drought Management Plan and the Water Restrictions Policy (No1:01:02). The Drought Management Plan restriction triggers are directly taken from the Douglas Shire Council approved Drought Management Plan.

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The following communication measures have been undertaken -

• A half page advertisement detailing the water restrictions and reasons for implementation was placed in the Port Douglas Mossman Gazette on October 2, October 8. • Local media taken on a site visit to the Rex Creek Intake to view low water levels. • Media releases issued on September 29 and October 7. • Community Service announcement issued to media on October 1. • Information of restrictions placed on Council website. • Variable message board placed in prominent locations on the Cook Highway at Craiglie and Port Douglas informing the restrictions are in force. • Communication sent to industry associations to distribute to members to notify business responsibility to reduce water. (Port Douglas Chamber of Commerce, Port Douglas Daintree Tourism) • Contact made with major commercial water users • Inspections by Water & Waste staff.

Council has reduced watering of Council land (e.g. parks and gardens, median strips and irrigation around Council buildings)

Level 2 water restrictions were introduced on 12 October. As a result, in addition to the above measures the following has been implemented.

• Advertisement in the Cairns Post on 10 and 17 October. • Media release issued 12 October. • Advertisement in the Port Douglas Gazette 15 October. • A daily water use update is being provided on ABC morning radio. • A daily water use update is being provided on Port Radio. • Water & Waste Education officer has commenced visits to local schools.

COMMENT:

A meeting was held with the DERM Regional Water Services Manager on 15 October to discuss the various applications submitted by Council. The outcomes are summarised below.

Application for temporary water supply

An application for an alternative temporary water supply from the Mossman River was submitted to the Department of Environment and Natural Resource Management on Friday October 2. The application is for an extraction point located on the Mossman River downstream of the Mossman Gorge Carpark. This water would be used to supplement the water supplies at such time as it is unsustainable to extract sufficient water to meet demands from the Rex Creek Intake.

At a meeting on 14 October DERM advised that they will expedite the approval process so that the community does not run out of water supply.

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Application to DERM for Internal Review of Water Licence

Council has requested that DERM review the upper extraction limit of 170 litres per second for periods when flows in Rex Creek are above 300 litres per second. The water treatment plant and associated infrastructure is designed to treat and supply up to 325 litres per second and with an addition rack of filtration membranes 390 litres per second. This would give Council the opportunity of fully utilising the gravity fed Rex Creek infrastructure for most months of the year for many years to come rather than pursuing a second raw water source in the short-term.

Further Water Restrictions

Based on the current dry period, Rex Creek flows and the water demand, it is highly likely that level 3 water restrictions will need to be introduced in the short term. These restrictions are considered severe and include a complete prohibition on garden sprinkler systems in addition to other items.

Future water planning

The recent events have highlighted the need to complete the Douglas area water planning report currently being finalised. It is anticipated that this report will be presented to the November 2009 Water & Waste Committee meeting. This report identified future water supply and infrastructure needs to cater for growth and demand in the medium to long-term.

CONSIDERATIONS:

Corporate and Operational Plans:

Corporate Plan 2009-2014 – Goal 4.2 – Encourage Wiser Use of Water by all members of the regional community

Corporate Plan: Goal 4.2 – Encourage wiser use of water by all members of the community

Statutory:

Water Supply (Safety and Reliability) Act 2008 Chapter 2 of this Act includes requirements for all Water Service Providers in to prepare and submit for registration a Drought Management Plan for each service area in which the service provider supplies Water.

The Act also provides penalties for failure to comply with water restrictions as follows:

1. Individuals – up to 200 penalty units 2. Non-residential - up to 1665 penalty units.

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Policy:

Cairns Regional Council General Policy No. 1:01:02 Water Restrictions Policy.

Financial and Risk:

The major costs associated with implementing the actions include the following:

• Hire and operation of the emergency supply pump at an estimate of $30,000 per month. • Transport costs to transport the pump to Cairns and return it to Newcastle estimate of $8,000. • Operating costs for the pump estimated at $10,000 per month. • Media advertising for water restrictions estimated at $10,000 in total.

Sustainability:

The following issues need to be considered and addressed –

• The amount of water extracted for consumption does not compromise the environmental flows in line with the current water extraction license conditions and water demand reduction targets specified in the CRC Drought Management Plan. • Emergency water supplies are secured to sustain water supplies to the affected areas • Limit the environmental impact of water extraction from the emergency supply extraction point on the Mossman River. An Environmental Management Plan must be prepared and submitted to DERM to support the application for temporary water supply.

CONSULTATION:

Consultation has occurred with the following groups:

• Department of Environment and Resource Management • Wet Tropics Management Authority • National Parks and Wildlife • Consultation with Traditional Owners needs to occur. • The Water Minister has also been advised of the current situation and has advised that the department will expedite the approval process.

OPTIONS:

That Council notes the content of the report.

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CONCLUSION:

That Council notes the content of the report.

ATTACHMENTS:

Nil

Erik Zesers Program Manager Water Demand Management

Bruce Gardiner General Management Water & Waste

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