Records flow from Warrnambool’s roof water harvesting system

Wannon Water’s innovative roof water harvesting system proved its worth on Sunday when it set a new record following intense rain.

Branch Manager Asset Planning Peter Wilson said peak inflows of 331 litres a second were recorded from across the system at around 5pm.

“During the eight hours from 4pm to midnight, we harvested 2.5 million litres of water which is enough to supply 17 houses for an entire year,” Mr Wilson said.

“This is rainwater that would normally be lost in run-off to stormwater. The harvesting system recognises rainwater is a valuable resource and reduces urban run-off problems including high stormwater flows, scouring of waterways and flooding.”

The water is collected from the rooftops of some north-east Warrnambool housing estates, sheds at the Gateway Business Park in Horne Road, the sporting precinct at Albert Park, and buildings at Warrnambool College.

The raw water is transferred via a dedicated pipe system to Wannon Water’s Brierly Basin. It’s then transferred to the Warrnambool Water Treatment Plant where it’s disinfected and becomes part of the city’s drinking water supply.

Nearly 90 per cent of Warrnambool’s drinking water is currently pumped more than 90 kilometres from the Otway Ranges.

Mr Wilson said Wannon Water was working hard to reduce reliance on the Otway supply by increasing roof water harvesting in Warrnambool’s growth areas.

“There are huge financial and environmental costs associated with pumping water such a large distance. Energy is a significant operational cost for our business so we've been working hard to reduce our emissions and provide future savings for our customers.”

On average, each home connected to the rainwater harvesting system collects 150,000 litres of water each year which is equivalent to the amount of drinking water they use.

The Victorian Government has co-invested $685,000 in the project through the Department of Energy, Environment and Climate Action’s Integrated Water Management division.