D11/6241 Water Quality Bulletin 2 March 2011 Update on blackwater in the River Murray system The blackwater event in the River Murray, the Edward–Wakool, the Goulburn–Broken, Lower Darling, Murrumbidgee and Loddon rivers is continuing. The severity and extent of this event is due to the prolonged drought followed by widespread and persistent flooding, as a result there has been several sources of blackwater. Poor water quality from these floodplains continues to have a detrimental impact on the River Murray, however, the effect is no longer as pronounced as in previous weeks. Water quality information compiled by the Murray–Darling Freshwater Research Centre, (MDFRC) indicates that Dissolved Oxygen (DO) levels around Barmah-Millewa Forest remain stable at non critical levels. DO monitoring at Taylors Bridge Road, and in Barmah Lake, still exhibits DO concentrations at critical levels. This has been caused by a recent flood pulse through the Barmah- Millewa Forest. Downstream of Barmah in the River Murray between Echuca and Robinvale DO concentrations remain at critical levels. A slight recovery of DO concentrations has been observed between Robinvale and Mildura. The Goulburn River, Broken Creek and Gunbower Creek daily average DO concentrations have stabilised at non critical levels except at the monitoring site Condidorios which is continuing to record extremely low DO concentrations. Monitoring in the Coliban River, and Loddon River at Yando Road continue to record high DO concentrations at non critical levels. In the Edward River at Deniliquin, the DO concentrations have continued to increase to non critical levels. DO concentrations in the lower Darling River are stable at non critical levels, except at Wentworth the DO concentrations continue to be near critical levels. Frenchmans Creek inlet regulator is continuing to record critically low DO concentrations. Physical re-aeration over the inlet structure is having a moderate positive impact on DO concentrations along the remainder of Frenchmans Creek to Lake Victoria. DO monitoring on Lake Victoria shows that DO has increased to non critical levels. A continuing trend of increasing DO concentrations have been recorded in the River Murray above Waikerie in South Australia. At all sites downstream of Waikerie to the Lower Lakes, DO concentrations continue to be stable at near critical levels. To provide information on water quality during the blackwater event in the River Murray system the MDBA releases a dissolved oxygen level status map and weekly bulletin. This map visually represents the most recent dissolved oxygen levels measured within a 10 day period for sites monitored by numerous agencies. This information can be accessed at the MDBA website, http://www.mdba.gov.au/water/blackwater on a weekly basis. D11/6241 To report fish deaths In Victoria contact the Environment Protection Authority on 1800 444 004 In NSW contact Fisheries, Department of Industry and Investment on 1300 550 474 In SA contact Fishwatch on 1800 065 522 For media information Contact the MDBA media office on (02) 6279 0141 or email [email protected] For NSW contact Office of Water media on 0407 403 234 For Victoria contact the Department of Sustainability and Environment on 0400 983 471 For South Australia contact the Department for Water media team on (08) 8463 6637 For further information on blackwater please visit the MDBA website www.mdba.gov.au .