Waste not, water not

The State Government is allowing Ku-ring-gai Council to use residents' money to save its water by using recycled stormwater to irrigate 10 local ovals and two public gardens.

Ku-ring-gai Council has won the State Government's approval and support as a result of its aqua-thinking.

The State Government last month approved Ku-ring-gai Council's application for an 8.6 per cent rates rise. The Sydney Morning Herald reported that the rise had been approved because Ku-ring-gai Council had taken on a project "the Government thinks is too hard to do itself — harvesting stormwater."

The environmental initiatives — valued at over $1.7 million a year — were prompted by a research project investigating local residents views on the environment. Mayor of

Ku-ring-gai Adrienne Ryan said there was a growing awareness in the community that more needed to be spent on the environment.

The average ratepayer will pay around $50 more than they did in 2003-04. Without the additional five per cent levy council says it could not fund these important environmental works.

The stormwater harvesting done by Ku-ring-gai Council will be used solely for irrigation purposes. Manager of Sustainability at Ku-ring-gai Council Peter Davies says the council will find strategic locations that need water for irrigation that are sufficiently downhill enough or have a big enough catchment area above it.

"We're looking at 10 ovals from across the municipality. What we're going to do then is tie it to our sportsground program where we upgrade our sporting ovals. We'll reconstruct the playing surface — bring more soil in, returf and then lay down the irrigation."

In terms of identifying the recipients of the stormwater harvesting, Davies says, "We're tentatively looking at The Glade, Wahroonga; Auluba Oval, South Turramurra and Lindfield Soldiers' Memorial Park. They're our top three sites that we'd like to do sooner rather than later."

Council is about to start work on a stormwater harvesting system at Barra-Brui Oval in St Ives for which they will collect water from a 14-15 hectare catchment area above the oval (which includes St Ives High School and Primary). Ironically, on the day the Observer speaks to Davies, construction has been delayed due to rain.

"That tank should provide the oval with 70 per cent of its irrigation needs. At the moment we don't irrigate at all, so that's 70 per cent on top of nothing. All going well we hope to be finished in about 12 weeks with the view to have the field in a completely playable condition by the end of the year."

In terms of treatment of the stormwater, Davies says there are no known sewer overflow points at the proposed locations. "But if we ever got higher than expected pollution readings we'd upgrade our disinfection process. At Barra-Brui we'll use traditional pop-up irrigation but sub-surface irrigation is obviously the most hygienic method and is favoured in the long term."

Council has been applauded for outlining such a committed environmental agenda. Hornsby Council is also exploring instituting a similar stormwater system at Pennant Hills Park.

"What this project is trying to do is to push along the water conservation agenda at a faster rate than what's happening at the state level.

"So State Government is very supportive of us working on these projects before they introduce their own arrangements," says Davies.

"What the levy will do is guarantee Ku-ring-gai its money, so we can double up on our investment. So while we've tentatively nominated 10 ovals to irrigate, we may be able to deliver many more."