Cold water pollution (CWP) results when the bottom cold layer of water from large, stratified dams is released downstream resulting in an artificial reduction in river temperatures during the warmer summer months. For native fish, CWP detrimentally impacts all life-cycle stages and is a key contributor to the loss of over half of expected fish species below the major dams in the Murray-Darling Basin (MDB).
The NSW Department of Primary Industries and Regional Development (DPIRD Fisheries) and WaterNSW are working collaboratively to mitigate CWP at Pindari Dam in the northern MDB via bubble plume technology. Bubble plume destratification has been used in dams globally for decades to limit cyanobacteria blooms and remediate poor water quality conditions caused by reservoir stratification such as at WaterNSW's Nepean and Woronora storages; however, bubble plumes also offer an opportunity to mitigate CWP.
Bubble plume technology is proposed to be used to destratify a large dam (Pindari) to mitigate CWP which will further strengthen the case to deploy this technology as an effective option at remaining high priority dams in the MDB. Assessments demonstrating the potential benefits of bubble plume destratification at Pindari Dam will be presented.