Wetlands Australia National Wetlands Update February 2013
Issue No. 22, February 2013
Concrete structures achieve environmental benefits
Jamie Hearn, Murray Catchment Management Authority
Inlet channel with habitat trees in place.
The planned completion of the Koondrook-Perricoota Forest Flood Enhancement Project (KPFFEP) in February 2013, will help highlight the role of water delivery structures in the efficient use of water in Australia.
The project will enable the environmental watering of up to 17 000 hectares of the Koondrook-Perricoota Forest. The water delivery structures will allow the operators of the scheme to target wetlands and other areas within the forest and achieve specific ecological outcomes identified within the Murray Darling Basin Authority's The Living Murray program.
Without these structures, a River Murray flow in excess of 30 000 megalitres per day through the Torrumbarry Weir is required to achieve a significant level of natural flooding. The same level of inundation can now be achieved by diverting flows of only 4500 megalitres per day through a newly constructed inlet channel and regulator. This inlet structure, coupled with the associated downstream regulators and levee, enables the timing, volume, depth and duration of watering events to be carefully managed.
The ability to maintain the health of the creeks and wetlands within the forest during times of drought and low flow is a major benefit of the project. These ecological systems are affected by the altered natural flooding regimes brought about by the construction of weirs and dams built to meet the demands of a growing economy and population, and the long term impacts of changing rainfall patterns.
The inlet regulator and channel have been designed with the needs of wetlands animals and fish in mind. The regulator includes fishways and a turtle ramp to reduce the risk of stranding in the forest. Even the radial aluminium regulator gates are designed to minimise fish damage. Additionally, the inlet channel has been lined with trees for fish habitat and refuge.
The finished project will ensure the long term health of the wetlands and creek systems within the Koondrook-Perricoota Forest, helping safeguard vulnerable aquatic flora and fauna for future generations. For further information visit Koondrook-Perricoota Forest Flood Enhancement Works Project .