Lake Bolac

This Lake Bolac project is a constructed passive wetland system for sewage treatment

The Lake Bolac Sewage Treatment Wetland is a constructed passive wetland system treating the municipal wastewater of around 230 residents and visitors. The overall system is well integrated into its surrounding environment, visually enhancing the landscape and improving the biodiversity of the area.

The project demonstrates a low-cost solution to sewage for a small unsewered regional town. The wetland system provides a range of value-adds (environmental, social, cultural) that elevate the project from a pure infrastructure provision to a natural and social asset for the township. The wetland treatment system not only treats wastewater but excess treated wastewater is beneficially reused to irrigate a biodiversity floodplain.

Key outcomes

• Development and implementation of a passive, low-cost sewerage system for a small, unsewered regional town
• Development of a new passive primary filtration method (gravity fed woodchip filter) which is appropriate for wider applications in small community Waste Water Treatment Plants (WWTP’s)
• Development of a new passive, zero discharge WWTP design prototype based on the use of multiple gravity-fed components in series (settlement tanks, woodchip filter, subsurface and surface flow wetlands)
• Development of a design and modelling tool to size and configure this type of WWTP as a commercial alternative to lagoons, constructed wetlands and mechanical WWTP’s for regional town communities