Water accounting methodology will be developed and agreed in advance by TLMC and the Basin Officials Committee (BOC). Consistency of water accounting methodology will be sought wherever possible. Where relevant, water accounting will be consistent with the Water Accounting Conceptual Framework and Australian Water Accounting Standards. The best available, most appropriate and cost-effective measurement technique will be used to determine environmental water use. The appropriateness of the measurement technique is likely to differ from icon site and event. For example, under dry conditions environmental water pumped into Hattah is likely to be measured via a meter and return flows measured via a gauging station. Under wet conditions, environmental water returning from Barmah–Millewa Forest and other upstream sites will need to be modelled. It should be noted that current calculations for barrage releases are estimates only, and a better calculation of discharge volumes is needed in the near future taking into account lake and estuary water level and bay openings.
4.5 Evaluation and management of potential risks
A number of risks have been identified associated with the Lower Lakes, Coorong and Murray Mouth Icon Site EWMP (Table ), adapted from DSEWPAC (2011). Monitoring and mitigation will be carried out where possible. The results will be taken into consideration when implementing adaptive management principles. These risks and mitigating measures are further detailed in a Risk Monitoring Plan. The risks identified have been linked to LLCMM icon site First Step Decision objectives where relevant.
Risks associated specifically with climate change including sea level rise and reduced inflows have been further explored in Matthews (2005) and Lester et al. (2009b).