Western Treatment Plant

[1] It forms part of the Port Phillip Bay (Western Shoreline) and Bellarine Peninsula Ramsar Site as a wetland of international importance.

[7] In 1892, the newly established Melbourne and Metropolitan Board of Works (MMBW) began buying land at Werribee, chosen for its low rainfall and suitable soils.

At a time when most cities dumped their untreated wastes directly into rivers and the sea, Mansergh advised treatment of Melbourne's sewage by broad irrigation with a capacity large enough able to deal with the expansion in population expected over 50 years.

The system he conceived and which was implemented in only slightly modified form began with a water closet at every property which delivered the sewage by gravity through a network of underground sewers of increasing diameter to a steam pumping station at Spotswood where it was forced up wrought iron rising mains to Brooklyn to begin its 25 kilometre journey along the Main Outfall Sewer to the sewage farm at Werribee.

It runs for approximately 27 kilometres or 17 miles from the old pumping station in Spotswood (now part of Scienceworks Museum) to the Western Treatment Plant, spanning the suburbs of Brooklyn, Laverton North, Williams Landing, Hoppers Crossing and Werribee in the cities of Brimbank, Hobsons Bay and Wyndham.

[7] Most of the Federation Trail, a major arterial pedestrian and bicycle path that runs for 23-kilometres from Werribee to Altona North, follows the heritage-listed Main Outfall Sewer.

[11] Using huge covers over the ponds, methane gas produced as a by-product of sewage treatment (known as biogas) is captured and turned into renewable energy.

The Western Treatment Plant generates 70,000 MWh annually which means that it sometimes exceeds its own need for electricity and exports it back to the grid.

Of this, about 28.051 billion litres of recycled water (mostly Class C) was used to irrigate 85 km2 of pasture for grazing 15,000 cattle and 40,000 sheep and manage soil salinity onsite, and to maintain the health of the Ramsar listed wetlands.

[2] In 1921 parts of Port Phillip Bay and Bellarine Peninsula including the Western Treatment Plant were declared a sanctuary for native animals.

The sewage treatment lagoons, Lake Borrie, creeks, saltmarsh, and coast host large numbers of sedentary and migratory waterbirds and waders.