Investigating Techniques to Reduce Evaporation from Small Reservoirs in Australia

Abstract

Climate change has been posing a great pressure on water resources, particularly in Australia. In South-East Queensland (SEQ), the annual evaporation is expected to rise by about 16 per cent in the next 60 years due to increasing greenhouse gas emissions. As the region relies on a large volume of stored water, the minimisation of evaporation is a key factor in guaranteeing availability of water in the future. This paper analyses the efficiency of some existing techniques in reducing evaporation from small dams within SEQ. The use of suspended covers, destratification systems and windbreaks was investigated using modelling. Of these techniques, suspended covers showed the greatest potential for reducing evaporation (in the order of 88 per cent). The efficiency of windbreaks was around 27 per cent, while the use of destratification system did not change evaporation rates. These results are encouraging, and further research is warranted to determine the cost-effectiveness and environmental impacts of the use of suspended covers and windbreaks to reduce evaporation from small dams.