Protecting platypus burrows with early water transfer

“Platypus select nest sites based on river heights, so as the dam operator, WaterNSW has an important role to play in helping protect platypus by making this early water release ahead of the irrigation season,” WaterNSW Head of Water Planning and Delivery, Ashley Webb, said.

“By releasing some water in late winter-early spring, just before nesting season, the higher river level will encourage platypus to build their nests higher up the banks.

“Then if we need to do a bulk transfer of irrigation water to balance storage levels in our dams later in the year from Split Rock to Keepit, the water will pass below the level of their nests, protecting the platypus and newborn puggles.”

WaterNSW is adapting it’s Split Rock dam releases to encourage platypus to nest safely during breeding season. Photo by Iain Stych.

WaterNSW is planning to release a total of 15,000 megalitres of water from Split Rock Dam over 13 days, starting on 26 August 2026. Flows will gradually increase from an initial 280 megalitres per day (ML/day), peaking at 2300 ML/day on 29 and 30 August and ending on 8 September.

The remainder of the Bulk Water Transfer, if required, will recommence in October, with the intention of maintaining Keepit Dam above 102GL (24%), through natural inflows and planned transfers.

“The water released from Split Rock will be captured and stored in Keepit Dam for use in the irrigation season from November to February,” Mr Webb said.

“Downstream landholders between Split Rock and Keepit will notice a rise in river levels by about one metre during the initial, late-August water release, depending on their location.

“This WaterNSW initiative will not only reduce environmental impacts but also give downstream landholders an indication of changed river conditions they can expect later in the year, if a bulk water transfer between the dams is required.”

WaterNSW will be holding a community information session from 5pm on Monday 8 September 2026 at the Manilla Golf Club to share further information and gather feedback on the first pulse. Split Rock Dam has a capacity of 397,370 megalitres and is situated on the Manilla River about 28 kilometres upstream of Manilla and 70 kilometres north-west of Tamworth. It was built in the 1980s to supplement supplies from Keepit Dam and meet increased agricultural demand for water in the Namoi Valley.

Keepit Dam has a capacity of 425,000 megalitres and is on the Namoi River about 40 kilometres upstream of Gunnedah. Completed in 1960, Keepit was built to increase the availability of water for irrigation, leading to increased agricultural production of cotton, lucerne, cereals, oilseed, wheat and vegetables in the region, and driving the growth of downstream towns including Gunnedah, Narrabri, Wee Waa and Walgett.