Environmental issues

Water

Murrumbidgee Valley environmental watering updates

Murrumbidgee spring environmental flow

OEH and the Commonwealth Environmental Water Office are planning to provide a spring 2013 environmental water release into the Murrumbidgee River to achieve several environmental outcomes. This includes watering hundreds of Murrumbidgee River wetlands to ensure continued recovery of these sites, which were severely impacted by the long dry period prior to 2010.

This environmental water release is part of the annual planned management of water outlined in the OEH Murrumbidgee Annual Environmental Watering Plan 2013-14, endorsed by the Murrumbidgee Environmental Water Allowance Reference Group (EWARG).

Helping the Murray cod in the Murrumbidgee

Once home to thriving populations of Murray cod, the Murrumbidgee River has received extra water flows in late 2012 to help create perfect conditions for this important native fish.

Find out why this iconic Aussie fish needs a helping hand and what happened when more than 200,000 megalitres of environmental water was delivered to ensure successful breeding.

Cherax Swamp and Hobblers Lake bounce back

Carp screens, regulators and environmental water are helping native fish, plants and wildlife thrive in long-stranded wetlands, north of Balranald on the Murrumbidgee River.

Find out how landholders are working with OEH to rehabilitate these wetlands and how this is boosting local vegetation, waterbirds, frogs and fish.

Upper Murrumbidgee Flow Enhancement Project

During 2012, OEH managed a Commonwealth-funded project to conduct a preliminary feasibility assessment of providing increased flows of environmental water in the Murrumbidgee River.

Public information sessions were held during February 2013, and this generated a high level of interest in the project and feedback from the community, particularly people living along the Murrumbidgee floodplain. Feedback was incorporated into a final consultant’s report that was provided to the Commonwealth in May 2012.

OEH expects that the final report will be provided to the Murray Darling Basin Authority to consider in the development of a Basin-wide flow constraints management strategy.

December 2012 update - Cherax Swamp to Penarie Creek water delivery

Environmental flows totalling around 8000 ML were delivered to the Paika and Narwie Wetland Systems, north of Balranald from early October to early December. This follows the 2011 watering of Paika Lake, which had not received water for over 100 years. The delivery of water to these wetlands supports floodplain vegetation and has created foraging habitat for thousands of waterbirds in the Narwie Swamps, Paika Lake, Cherax Swamp, Hobblers Lake and Penarie Creek.

landholder and OEH staff in front of regulator

Landholder Paul Connellon and James Maguire (OEH) with a new regulator enabling flooding of the Lower Yarrawol Creek wetlands for the first time in 20 years. Photo Lisa Thurtell, OEH

Pipes and culverts, funded by OEH and the Australian Government’s Biodiversity Fund, have been installed to facilitate water delivery to the wetlands. These works are part of a long-term conservation project to improve the health of the Paika and Narwie wetland systems. They also allow a greater proportion of the floodplain to be watered, resulting in the recovery of stressed black box and river red gum.

Local landholders have also fenced off Cherax Swamp and Hobblers Lake from stock and planted wetland plants native to the local area. Importantly, carp screens were also fitted at key locations to prevent the movement of adult carp into the wetland areas, benefiting native fish populations.

Telephone Bank bird breeding

In late October, landholders in the Nimmie-Caira wetlands observed thousands of glossy and straw-necked ibis preparing to breed. As ibis and other waterbird species nest on lignum bushes and reed beds at water level, it is important that water levels remain stable to prevent adult birds from abandoning nests.

OEH, with the support of landholders and State Water, will provide up to 6000 ML to support the waterbirds and provide suitable conditions to allow the breeding event to be completed. As ibis chicks can take up to 49 days to become fully fledged, it is likely this water event will continue until January 2013.

Lower Murrumbidgee fish flows

Environmental water was released down the Murrumbidgee River to encourage native fish breeding, particularly threatened species such as Murray cod and trout cod. This was part of a cooperative environmental watering action with the Commonwealth Environmental Water Office, developed in consultation with the Murrumbidgee Environmental Water Advisory Group.

To maximise fish breeding success, steady flows of around 6000 ML/day were maintained downstream of Darlington Point, from mid-October through to mid-December.  

Water quality, fish movement and breeding response are being monitored by Charles Sturt University, Murrumbidgee CMA, NSW Fisheries and OEH as part of the Commonwealth Environmental Water Office’s monitoring project. NSW Fisheries has already observed river blackfish, Australian smelt and Murray cod larvae in the river.

Page last updated: 08 August 2013