News
Good news underground for future water supply
Trial-pumping of Westernport Water’s new bore network finished on June 12 and initial results are looking better than anticipated.
Water quality improved 25% over the 60-day test pump and water flow proved sufficient to supply between a quarter and a third of the region’s ongoing daily requirements.Testing of the Corinella aquifer will now be suspended for a month while hydrologists test how long it takes for the underground supply to replenish.
Last January, Westernport Water engineers installed a 100m deep bore which yielded a megalitre a day. Average daily demand within the region is between 3-4ML.
The water was fed through pipes to storage at Candowie Reservoir and needed no special treatment. In fact, according to project engineer Helden Leereveld, the water quality improved over the pumping cycle. “The water initially contained moderate quantities of minerals and salts but these diminished; levels fell by 25% over the time,” he said.
“This is possibly because the water flow has flushed them through the underground system.”
The engineers also audited all bores within a 3km radius of the Westernport Water bore before conducting the pump test.
The audit was taken to make sure that no other bore user is adversely affected by Westernport Water’s bore coming on-line.
Acting managing director Keith Gregory said: “So far there has been no negative impact on other bore users of the area. The bore audit gathered information including groundwater levels, bore depths and how individual bores are being used.
“The information obtained will be extremely valuable to determine how the aquifer interacts as a whole, how much water can be extracted sustainably.”
Results of the audit and test-pump will be shared with Southern Rural Water (SRW), the regional groundwater supply authority. Westernport Water is seeking a groundwater allocation from the aquifer and expects a decision from SRW by the end of the year.
Mr Gregory said: “The bores are part of the overall plan to further secure water supply across the region.
“This audit gives us all a starting point and will act as the benchmark. We know groundwater is a shared resource and we are committed to using it responsibly.”
Pumping trials on the corporation’s two shallower bores in King Rd and Cemetery Rd will start in July 2008.