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Resilient urban systems:
a socio-technical study of community scale climate change adaptation initiatives
WestWyck residents rely on the following water systems and services that are managed and maintained by
a combination of institutions and stakeholders:
• Centralised reticulated water supply
• On-site greywater treatment and reuse
• On-site blackwater treatment
• Rainwater collection and use
• On-site storm water collection (WSUD)
Reticulated potable water
is supplied to each allotment via the mains water distribution network. The retail
water utility has responsibility for water quality and water provision to the water meter at each allotment.
Grey-water
produced on site drains to a shared treatment system. Greywater is treated to ‘Class A’
standard for use in household toilets, laundries and on gardens. A pressurised tank is used to store treated
water and has a manual back-up switch for mains supply if treated grey water fails quality tests or runs low.
WOC is responsible for on-going operation with responsibility for maintenance, upgrades and monitoring
contracted to a commercial operator.
All
black-water
produced on site drains to a shared treatment system. From here a small (but unknown)
volume of accumulated solids is pumped daily to the mains sewer. Clarified liquid drains into sealed and
vegetated evapotranspiration beds containing plants chosen for their high transpiration rates. Excess
liquid overflows to the mains sewer. WOC is responsible for on-going system operation. Maintenance and
monitoring is contracted to a commercial operator. The local water utility is also responsible for ensuring the
mains sewer exists as a backup for sewerage disposal if the on-site system were to fail.
Rainwater
is collected from each townhouse and stored in individual 5000L under-deck tanks. Rainwater
is also collected from the main apartment building and stored in visible tanks onsite. Water is pumped
from each tank to roof-mounted hot water units and connected to external taps. As backup, mains water
is also plumbed in and connected via an automatic switch if rainwater supplies run low. All aspects of the
rainwater system maintenance fall under WOC’s responsibility. The WestWyck site has also been designed
and landscaped to minimise stormwater runoff following
WSUD
principles. This is achieved through a
combination of rainwater collection and reuse, porous surfaces, communal rain-gardens and infiltration
beds to collect excess rainwater. WOC is formally responsible for on-going maintenance of WSUD
features. However, a number of residents are active in providing many of the maintenance services required
(independent of any WOC decision) such as seeding garden beds and infiltration areas.
The energy and water systems used at WestWyck reflect the developers’ vision of an eco-village designed
on environmental and community ideals. Initial development concepts were strongly influenced by concerns
over unsustainable resource consumption and a belief in the need to reduce the environmental impact of
urban developments. These concerns translated into an emphasis on maximising localised production and
reducing demand on external resources.
Initial concepts were not always feasible and current system configurations are the result of a multi-
year learning and adaptation process. For example, despite initial aims, water self-sufficiency was later
considered too ambitious. Nevertheless, designs were influenced by concerns over environmental
conditions consistent with climate change projections, particularly drought.