Simple Indicators for water resource management

Early warning of water shortages allows for improved water resource management. In years of below average rainfall, inflow into water supply dams is reduced, which may lead to water availability below demand and a need for alternative water supplies. The DoW developed a suite of simple indicators to track the 2013 winter in South West Western Australia. Tracking rainfall throughout the winter season allowed for quick and simple monitoring of the state of the water resources. The project team developed three types of indicators: rainfall for target inflow, storage probability tables and multiple year scenarios. Rainfall trigger values for a variety of target inflows were developed to track storage volume of water supply dams. Historical records of dam storage levels were used to determine the probability of achieving desired target storages by the end of October 2013. The use of multiple year scenario indicators was trialled to gain insight into water resourcing issues in the longer term.