Highway to the hydro-zone

With the City of Nedlands in Western Australia managing a large number of parks, reserves and sporting ovals, there has been a key focus on improving water efficiencies in the irrigation of these areas over recent years.

The City has continued to participate in the Water Corporation’s Waterwise program – and a key component has been the undertaking of best practice hydro-zoning.

City of Nedlands Chief Executive Officer, Greg Trevaskis, said, “Hydro-zones within each public space are separated and managed specific to their needs, reducing overall water use, taking into account the varying irrigation requirements of high-profile turf, active turf, passive turf, native gardens, low passive gardens and areas well-shaded by infrastructure or mature trees.”

Building retrofits have also been undertaken by the City to swap out old infrastructure for new that use less water, with waterwise showers, toilets and taps being installed in public buildings.

Mr Trevaskis said the City had started to develop strategic management plans for each managed area of public open space, known as ‘enviroscape precinct master plans’.

The natural areas within each precinct are identified and categorised as a planting zone, sports turf, eco-zone, casual-use turf or greenway and water distribution is allocated accordingly.

To address the potable water utilised for verges and roundabouts, small but successful projects are being undertaken to hydro-zone areas or irrigate lawn turf without compromising street appeal.
“In one example, a verge adjacent to a City-owned sump has been upgraded with large rocks, small native plants, pea gravel and grass trees to eliminate the need for automated irrigation.”

The City has trialled the use of EZ-FLO technologies before implementation in City parks, as part of the irrigation infrastructure.
While contributing to a 20 percent water saving in the parks trialled, there was also a noticeable 15 to 20 percent improvement in grass plant health and sustainability.

“Irrigation on the City’s parks and ovals can also be automatically and remotely controlled.”