Over the years, the New South Wales town of Glen Innes had investigated numerous water storage options to address the town’s need for improved water security, with many ultimately being discarded.
However, the Glen Innes Severn Council’s purchase of the Glen Innes Aggregates Quarry in July 2011 allowed it to not only address water security in a cost-effective way but to secure gravel materials for both the council and NSW Roads and Maritime Services’ projects as well. In addition, the quarry also supplies aggregate, sand and road base to the public for general construction and concrete work.
While continuing the normal operation of the basalt quarry, the council began to convert the quarry pits into off-stream water storage areas.
In a 2012 entry for the Federal Department of Infrastructure and Regional Development’s Innovative Infrastructure Development Award, the council explained: “Two pits exist within the quarry, allowing council to alternate extraction operations between the two, progressively expanding water storage volume as minerals are extracted.
“One pit is initially being converted to a 250-megalitre off-stream storage while extraction continues in the second, which will be shaped for optimum water storage through normal extraction activities. That pit will then be utilised for water storage as the first pit is also worked into final shape, with the final volume expected to be in excess of 1300 megalitres, more than double the town’s current storage volume.”
Funding helps to “drought proof” town
The council is currently looking to develop the quarry’s northern pit. A NSW Public Works geotechnical investigation showed that the pit would be suitable for both short- and long-term water storage, but noted that the sides of the pit would first need to be reshaped and lined with clay material before it would be able to hold water.
The council was recently awarded $970,000 as part of the NSW Government’s Water Security for Regions program, which will be used to fund storage augmentation, pipeline and bore works, as well as water efficiency mechanisms for the project. The quality basalt has already been quarried from the northern pit and only 50,000 tonnes of sub-grade material remains to be removed.
“Development of the northern pit will include removal of the sub-grade material, battering the banks, relining of the pit, and putting in submersible pumps, aeration and associated pipe work,” the council’s manager of integrated water and sustainability services Keith Appleby said.
“A solar electricity system will also be installed at the quarry to reduce operating costs, and a shallow solar pump will be installed in the southern pit to return the minor leakage of water to the supply. Council also proposes to increase water storage capacity through upgrading the existing bore on the Red Range Road, and installing a second bore nearby, as well as installing another bore at the quarry.”
Appleby stated that the recent funding would assist Glen Innes in withstanding drought and that it would effectively give the town 14 months of additional water storage after the town’s main water supply, Beardy Weir, was fully depleted.
Council quarry strategy holds water – for now