Before being discharged, wastewater is currently flowing through a small pond, characterised by dense macrophtyes. Water quality sampling revealed that the concentration of pollutants decreased rapidly after the wastewater passed through a small pond located on-site. This result is consistent with the fact that the majority of pollutants associated with swimming pool water are particulates, due to the action of coagulants. Based on this success, and because there is no sewage system, Lake Macquarie City Council is considering expanding this structure. Removing particulates and letting water stay in the pool so that chlorine can dissipate would greatly assist the treatment of backwash water.
Artificial wetlands offer great potential for treating water before disposing of it.
Disposal of backwash water to the sewer Lake Macquarie City Council found that the most feasible option for disposing of backwash water from one of its pools was to use the sewer. This option was chosen based on difficulties in treating the water and due to site characteristics that limited the potential for treatment and reuse. It was therefore necessary to install holding tanks which could hold the volume of wastewater generated at each backflow. Water is pumped into the tanks and then allowed to discharge by gravity at a controlled rate over 2-3 days. Although this method involved extensive capital works initially, it is expected to have minimal ongoing operational costs.