Water Sharing Plan Part Suspension for Peel Valley Regulated, Unregulated, Alluvium and Fractured Rock Water Sources 2010
Reason for decision
The Peel River Regulated Water Source is currently declared as Stage 4 (Critical Drought) under the NSW Extreme Events Policy. Under this stage, critical human water needs have priority for the management of remaining water supplies.
Chaffey Dam is currently at 15.7% capacity (2nd December 2019) and, if measures are not undertaken to conserve supplies, could be unable to supply Tamworth’s needs by June 2020 if drought conditions persist.
The NSW Government has committed an initial $5.3 million to complete water security projects to extend essential town water supplies to Tamworth, Moonbi and Kootingal and a further $39 million for a pipeline from Chaffey Dam. These works are being carried out by WaterNSW in two stages.
WaterNSW has constructed a temporary block bank as a weir on the Peel River near Dungowan. Water released from Chaffey Dam will flow down the river until it reaches the weir, and then will be piped into the Dungowan to Tamworth pipeline. This will assist in maintaining water supply to Tamworth until the second stage - the permanent pipeline from Chaffey Dam to the Dungowan pipeline is completed.
To minimise transmission losses associated with releasing water daily from Chaffey Dam, the rule in the water sharing plan requiring this daily release has been suspended.
Reasons for decision
Water Sharing Plan suspension – section 49B
Section 49B of the Water Management Act 2000 enables all or part of water sharing plans to be suspended if the Minister ‘is satisfied that there is an extreme event in relation to a particular Basin management area or part of the Basin water resources’. An extreme event includes an extreme dry period. The NSW Extreme Events Policy details how water should be managed during these extreme events. The priority is to secure critical human water needs.
The extreme events policy framework sets out 4 stages of operations – from normal operations in Stage 1 up to critical drought or water shortage in Stage 4. The suspension of parts of a water sharing plan is listed as a management tool for Stage 3 and Stage 4 events.
Before suspending the operation of all or part of a plan, the Minister must obtain the concurrence of the Minister for Energy and Environment. This concurrence has been received.
Benefits and risks
Suspension of planned environmental water provisions clauses
The suspension of clauses 31(3) will enable WaterNSW to release environmental water from Chaffey Dam on a pulse release basis, rather than the daily release required by the clause.
Rather than releasing 3 ML per day, WaterNSW will release up to 30 ML per week. This will reduce transmission losses, but will mean there may be days where no releases are made.
Releasing water on a pulse release basis will allow water to remain in the river while also periodically connecting key refuge pools that have been identified by the Department of Primary Industries as being important for local fish populations.
The suspension will be remain in place until 30 June 2020. By that time, further details will be available on how releases from Chaffey Dam will be managed once the pipeline to Dungowan is completed. The rule may be further suspended.