Oaklands Park - stormwater MAR
The Oaklands Park Wetland and Stormwater Reuse Scheme is an innovative project that ultimately provides treated stormwater to irrigate up to 30 neighbouring council reserves. The site is located adjacent to the Oaklands Estate Reserve, a major recreational park in the City of Marion, South Australia.
This project captures and reuses water from the Sturt River that would otherwise be discharged downstream. This is achieved through harvesting pumps, a gross pollutant trap (GPT), and a 2.3 hectare Oaklands Wetland with cascades and macrophyte plantings. All these steps are required to treat the harvested water to a suitable level for injection into the deep aquifer below the site. The water is continually monitored for conductivity, pH, temperature and turbidity. Water treated through the wetland is collected into an underground sump where an injection pump delivers water under pressure into four wells. This Aquifer Storage and Recovery (ASR) scheme can store up to 400 million litres of stormwater each year. ASR is a form of Managed Aquifer Recharge (MAR) see https://www.waterindustry.com.au/MARHub for more.
A recovery pump in each well backflushes water and circulates to the head of the wetland to control level/quality, and also transfers the treated water to a buffer tank. This tank feeds two distribution pump stations which distribute water through an 11.5 km long underground network of pipes to metered outlets at nominated council parks/reserves for the purpose of supplying water to their irrigation systems.
This stormwater reuse scheme not only relieves the pressure on drinking water supplies, but also reduces the pollutant loads from stormwater that would otherwise flow downstream to adversely impact marine life in the Gulf St Vincent. The wetlands provide a diversity of flora and increase the biodiversity of the area with a safe environment for recreation.
This project was fortunate to win Parks and Leisure Australia’s 2014 Regional award for Sustainable Initiatives as well as Stormwater Australia’s 2014 National Award for Excellence in Integrated Stormwater Design against other inspiring projects around the country.
HydroPlan was responsible for design and supervision of the "mech and elec" contract for pumps and pipes that harvest, inject, recover, and distribute the water, and also the "distribution" contract for piping (horizontal directional drilling) the water to Council reserves and recreational facilities.