Lismore sewage treatment upgraded for environmental sustainability

Source: rmit.edu.au.

Lismore City Council (LCC) has revamped an 80-year-old sewage treatment plant, transforming it into a environmentally-friendly asset designed to cater for a growing population.

The $25 million South Lismore Sewage Treatment Plant was five years in the making, and uses intermittently decanted extended aeration (IDEA) to treat sludge.

It is also home to a 334 kW solar farm, which generates about 30% of the plant’s electricity.

While IDEA is commonly used, LCC project manager Paul Smith said Lismore’s is the first optimised facility, using additional technology to make the plant more efficient.

“This new plant represents the first Australian application of an optimised IDEA process and also cloth media filters with a 5-micron nominal aperture,” Smith said.

“That won’t mean much to non-scientists … but it means we’re using a very fine filtering technique.

“We’re creating a much cleaner effluent that’s better for our environment, and also utilising biological means to remove phosphorus rather than using chemicals.”

The plant took out an asset management gong at the Local Government Awards recently, with LCC recognised for its focus on innovation and delivering the project on time and under budget, despite Lismore experiencing a severe flood during construction.

Smith said optimising the plant would save $400,000 per year due to less chemical usage, reduced biosolids disposal, and less electricity use.

“That is a significant saving for ratepayers and greatly reduces the ongoing operating budget over its lifecycle,” he said.

The decommissioned plant, which was built in 1939, was demolished and landscaped to provide 5000-square-metres of flood-free land ready for development.