Unitywater has completed the drilling and construction of an 820 metre pipeline under the Maroochy River as part of an $11 million project to transfer sewage from the communities of South Marcoola, Mudjimba, Pacific Paradise and Twin Waters to the Maroochydore Sewage Treatment Plant (STP).
This achievement sees the completion of stage one of a three stage project that incorporates the construction of a six kilometre 560mm diameter pipeline and a new transfer pumping station that will connect the existing sewerage network to the Maroochydore STP.
Unitywater Executive Manager, Infrastructure Planning and Capital Delivery, Simon Taylor said the Suncoast STP is operating at capacity and Council’s original plan to expand the facility to cater for anticipated population growth in the area was estimated to cost $34 million.
“Building the pipeline to a plant which already has capacity available is a much less expensive and more environmentally-friendly solution, saving close to $20 million in capital works and keeping costs as low as possible for our customers,” Mr Taylor said.
Because traditional excavation and trenching was not possible under the Maroochy River, Unitywater used horizontal directional drilling (HDD) to install the pipeline, avoiding any unnecessary environmental impact and minimising surface disruption.
“We are pleased with the successful outcome of the drilling operation. The route was a complex one and required the rig to drill horizontal and vertical bends as it made its way under the river,” Mr Taylor said.
Suncoast STP will be decommissioned after the completion, testing and commissioning phases of the new sewerage rising main and new sewage pumping station in the second half of 2014.
This project is part of the $680 million capital works program Unitywater is rolling out over the next five years to increase the network capacity and cater for future population growth in the region.