Water for the environment delivery

Planning for the delivery of water for the environment in 2024-25 is continuing. Given the projection for reduced flows in August, operation of the Chowilla environmental regulator is highly unlikely and planning is now focussed on the pumped delivery of water for the environment to a number of Chowilla wetlands.

Planning for the operations of Pike and Katarapko floodplain environmental regulators is continuing.

At Pike floodplain, a low-level operation potentially up to 15.3 m AHD (75 cm above normal level at the Pike regulator) is proposed along with minor raising at Lock 5 by 10 to 20cm. The regulator operation is scheduled to commence in mid to late August. Targeted pumping may also be undertaken at two sites to water regenerating lignum and black box.

At Katarapko floodplain, areas of the floodplain wetlands are undergoing a drying phase. A low-level operation may be undertaken to raise water levels behind The Splash regulator by up to 2.0 metres to 12.0 m AHD with a concurrent 10 cm raising of Lock 4. However, further monitoring and modelling is underway to confirm this operation.

Weir pool manipulation within normal operating ranges at the other SA locks and weirs is under consideration.

The floodplain environmental watering actions aim to sustain the significant improvements in condition and regeneration of trees, lignum and understorey vegetation and provide important habitat for frogs, waterbirds and other fauna. The final decisions to proceed with these operations will depend on River Murray flows, environmental water availability through the latter half of 2024 and approvals, and will be informed by the outcomes of environmental monitoring and consultation.

Water for the environment continues to be delivered as part of SA’s entitlement flow. Flows at the SA border have now reduced and are expected to remain in the range of 4-6 GL/day throughout August.