New tech key to water-sensitive urban developments

Posted 29 August 2016

Water-sensitive urban developmentsSmart water tanks, onsite water treatment and innovative stormwater drainage – these are a few of the tricks the new breed of water-sensitive urban developments are deploying to slash water use.

Population growth and increasing urban development is putting pressure on urban water supplies across the country and creating a boom of interest in water-sensitive urban design, as demonstrated by a spate of innovative new housing developments.

In Lyndhurst, 35km south-east of Melbourne, South East Water has teamed up with property developer Villawood to build a 42-hectare, 460-home development that is predicted to use 70% less mains water than an equivalent average development.

The precinct will include rainwater tanks on each residence to supply treated rainwater to hot water systems, and an onsite wastewater recycling treatment plant for non-potable use.

But one of the biggest innovations comes through remote-control telemetry technology that South East Water developed.

For example, the system will use forecast data from the Bureau of Meteorology to adjust existing volumes in the rainwater tanks to maximise the capture of rainfall. It can also communicates with the development’s sewer system to better manage peak flows by only releasing wastewater from each property’s tank when the system can handle the load. 

The system is predicted to reduce peak stormwater flows by up to a quarter, minimising sewer excavation. With smaller pipes throughout the network and the use of horizontal drilling, large-scale excavation and its expense are eliminated.

On the other side of the country, Landcorp’s White Gum Valley development in Fremantle is also innovating in its approach to dealing with stormwater.

LandCorp Sustainability Manager Greg Ryan said a whole-of-development approach to sustainability was adopted from the outset. The entire water cycle was considered, including the water that comes into the precinct, is stored, is used, and which leaves the precinct. 

“All stormwater up to the one-in-100-year storm event is infiltrated on site through a combination of permeable surfaces, drainage cells, flush kerbs, and the use of micro swales and vegetated basins,” he said.

Each lot will also be connected to not just mains but also a “purple-pipe” community bore connection, as well as a metered rainwater tank.

On a larger scale, planning is well-advanced on Huntlee, a 7500-dwelling town in NSW’s Hunter Valley that aims to recycle 100% of wastewater, courtesy of an onsite membrane bioreactor.

Harvesting and purifying the development’s wastewater will reduce the need for wastewater infrastructure, the environmental impact of wastewater removal and the reliance of the development on mains water.

To find out more about water-sensitive urban developments, read the full feature in the latest digital edition of Current magazine.