Back Up Dam put to the Test

Power and Water is about to begin a project at Manton Dam to test the water quality in the dam under a range of conditions.

The project will help Power and Water to deal with any water quality issues that may arise should the dam be called on to provide an emergency supply.

The results of the project will also provide information that will allow Power and Water to consider how and when Manton Dam may be returned to service in the future as part of its Darwin region water supply source strategy.

Power and Water’s General Manager Water Services, Paul Heaton said the project, which will start on 1 May, will determine the quality of water extracted from the dam at various levels.

“While Manton Dam has always been the emergency water supply source for the Darwin region, there is not a clear understanding of the water quality issues we’ll face should it be needed for drinking,” said Mr Heaton.

“Currently Power and Water has a license to extract around 7,300 ML a year from Manton Dam. The project will see this amount released into the Manton River over the next seven months with a program of water sampling and environmental monitoring.

“The project will run throughout the dry season and up until the beginning of the next wet season.

“The water level in Manton Dam reduces each year by about 1.4m due to evaporation, environmental releases and seepage. While this project will see water levels drop further than this, areas that will be most affected by lower water levels already have restricted access and are not available to the public for recreational use.

“During and after the project, current recreational uses including fishing and water skiing will not change. Power and Water will ensure that the boat ramp will remain serviceable at all times.”

Over the next two weeks, Power and Water will meet with representatives of Manton Dam user groups including the Darwin Water Ski Association and the Amateur Fishermen’s Association of the Northern Territory, to discuss the project.

For more information on the Manton Dam 2008 Water Quality Sampling project click here.