Water at WestWyck – An integration of small and large scale water systems
Posted in RDAG by CBiggs on July 13th, 2009
This ‘eco-village’ project is the brainchild of the WestWyck developers and originated from a community effort to preserve a historic local school building in Brunswick. Resource efficiency has played a major role in shaping the site’s design and construction. The village consists of 5 townhouses and seven apartments with a second stage planned. VEIL has been particularly interested in how water is managed there.
Water is handled on the site using a series of different methods to harvest, minimise use, treat, recycle and manage discharge from the site. Drinking water is supplied via the mains distribution system but unlike most residences in Melbourne, demand for mains water is substantially reduced through the integration of multiple on-site water technologies.
Rainwater is collected from all roof spaces and stored. Each town house has an underfloor tank of 5000L capacity and the apartment building connects to two 11000L tanks. The rainwater is primarily used for hot water but is also connected to hoses for garden use.
Stormwater from tank overflow and hard surfaces is diverted to planted swales. The swales are designed so that water flows slowly toward the property boundary infiltrating deeper into the ground along the way. Total stormwater outfall from the site has been cut by 97% from original levels.
Greywater is collected from all users and treated on-site to a very high standard. Post-treatment, the water is used for toilet flushing and laundry use. It can also be used for sub-surface watering in the garden. The greywater system was not cheap but became more cost effective once the number of dwellings reached twelve.
Blackwater from toilets and kitchens is treated on site in a system that can also deal with household food waste. A small amount of post treatment sludge is pumped to the wider network sewerage network for 1 minute per day. Post-treatment, clarified water is diverted to planted beds that are lined to prevent seepage to groundwater and vegetated with species that maximise evapotranspiration.