Reducing evaporation from water storages
The evaporation suppressant applied in the foreground to the surface of a trial dam at St George in Queensland. It suppresses wave action as it advances, resulting in a more reflective surface emanating from the point of application toward the far side of the dam.
Evaporation from water storages is a major problem for both urban and rural Australia, especially during hot weather and prolonged dry periods when water becomes scarce and agricultural productivity suffers. The CRC-P has developed improved chemical technology for the suppression of evaporation and is now undertaking a series of larger-scale field trials to assess its cost effectiveness for reducing evaporation on farm water storages.
The CRC-P research team at The University of Melbourne (UniMelb), led by Professors David Solomon and Greg Qiao, has studied the properties of chemicals that spread out across water to a form thin (monomolecular) layer which reduces evaporative losses, and then developed improved chemical technology for enhancing their performance. This technology is protected by a patent application which is now granted in several countries. The development of this technology has progressed from laboratory experiments and testing, to experiments in wave tanks conducted by Griffith University, and then to trials on small (220 square metres) open bodies of water conducted by NSW DPI. The CRC-P welcomes the involvement of BASF in this project. BASF brings production and chemistry know how as well as extensive links within the water intensive mining and agriculture sectors all of which will be important in the potential scale up of this technology.
Some members of the CRC-P research team at a field trial site (from left): Dr Emma Prime, Professor Greg Qiao and Dr Andy Leung (all from UniMelb) and Dr Harnam Gill (NSW DPI)
The most recent stage of this development involves undertaking a series of field trials on cotton dam storages that are typically 3-10 hectares in surface area. Each trial is being conducted using one dam as a control and applying the evaporation suppressant compositions to at least one nearby test dam over a period of several weeks when the dams are not in use and evaporation rates are high. By accurately monitoring the changes in the water levels of the dams prior to and during the trials, and accurately recording the weather conditions throughout the trials, the efficiencies of the test evaporation suppressants under the prevailing conditions are determined. The aim is to undertake field trials in different environments to optimise development of an evaporation control product and to provide reliable information to prospective end-users on the cost-effectiveness of this technology and how best to deploy the potential product under different conditions. It is intended that this information will be compiled into a database so that end-users can determine when to use this technology, and the savings they can expect to achieve.
Coliban Water is also another CRC-P participant involved in this activity which has benefited from the financial support provided by the CRC program, the Victorian Government, and the Cotton Research and Development Corporation.
