Water restrictions to begin from Monday, borefield tests ongoing
Friday, 5th December, 2014
By Andrew Robertson
Residents will be forced onto water restrictions on Monday as investigations into a borefield near Lake Menindee have already revealed “potential for a reasonable flow”.
Essential Water said yesterday it was introducing Level 1 restrictions because consumption of treated water had risen above 16 megalitres per day for three consecutive days.
Water operations manager Guy Chick said that a “major drought period is looming” and the restrictions would help prepare residents for more serious bans, should they be required.
“Level 1 restrictions are not difficult and, if anything, simply promote efficient water use,” Mr Chick said in a statement.
The restrictions include the banning of sprinklers, automatic watering systems and fixed or hand-held hoses between 10am and 7pm.
Residents flouting the bans face a written warning.
Level 2 restrictions will be introduced when the Menindee Lakes storage falls below 12 months’ town supply or when raw water salinity is above 1820 electrical conductivity.
Meanwhile, work at the borefield site near Lake Menindee will enter the next stage after the first test bore showed potential for a reasonable flow of water.
Crews began drilling on Saturday about 1.8km east of the interconnecting channel between Lake Menindee and Copi Hollow and next to the Broken Hill pipeline.
A spokeswoman for the NSW Office of Water (NOW) said yesterday that by Wednesday afternoon the test bore had reached a depth of 225 metres, just 25m short of its ultimate depth.
“I have been advised that they hit coarse sand at 205m which is good as it indicates that there is potential for a reasonable flow of water,” she said.
“Once 250m is achieved then the drill team will move to place a screen into the hole and develop it up; that is, put in the casings and move to the pump test.
“This pump testing will be the next milestone - it will tell us what the bore may yield via its recovery time.”
Test bores are used to gauge the quality and quantity of groundwater.
According to the spokeswoman, 17 sites have been investigated for test drilling and “where we go next will be dependent on the pump tests from this test bore”.
Since Water Minister Kevin Humphries announced plans to investigate groundwater as an emergency supply for Broken Hill in September, it has been met with criticism and suspicion.
The project was to have started last month but was delayed after the discovery of Aboriginal artefacts.
The spokeswoman said Aboriginal monitors have been on site during drilling which is expected to be completed by December 14.
Meanwhile, work continues to secure water in the near term for residents of Broken Hill, Menindee and Sunset Strip, as well as for Lower Darling landholders.
More than 4500 megalitres have now been pumped from Pamamaroo into the deeper Copi Hollow as part of the government’s emergency drought response.
Pumping will continue into the New Year until Copi is filled with 12000 megalitres, enough to supply Broken Hill for the next 12 months.
Water NSW (formerly State Water) said pumping was likely to last slightly longer than anticipated to accommodate losses from wetting up the storage banks and evaporation.
Elsewhere, works were progressing to transfer some of the remaining water in the upper Lake Tandure to the river channel of Lake Wetherell.
Water NSW said a small, temporary earthen block bank was finished this week in the artificial channel between the two lakes, while dredging had also stated to improve access to the residual pool in Lake Tandure.
“A temporary pumping station is likely to be installed in the second week of December to lift up to 15000 megalitres from Lake Tandure into Lake Wetherell,” a Water NSW project bulletin said.
Construction is also expected to begin early next year on block banks to hold back water for permanent plantings and to provide stock and domestic supplies for landholders.
Last month the State Government said it had set aside a further $400 million for infrastructure to secure the city’s water supply with a pipeline to the Murray River one of the options.