“This was an opportunity for local government to innovate and demonstrate how it can use local resources to solve a local problem - which potentially has national if not international application

Orange stormwater to potable: Building urban water supply diversity

Cooperative Research Centre for Water Sensitive Cities

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Project Overview

The regional city of Orange is located approximately 260km west of Sydney in the Central West of NSW. Water supply in Orange was provided by two water storages which captured runoff from predominately rural catchments. By late 2007 the city’s water storages were below 40% and significant resources were directed to reduce water consumption. The Blackmans Swamp Creek and Ploughmans Creek stormwater harvesting schemes are capable of providing an average of 1,350ML/year of additional water into the Orange’s raw water supply each year. This results in up to 25% of the city’s water needs being supplied stormwater collected from the urban area.


Orange City Council is responsible for water supply, wastewater management and stormwater management in the area. Council’s role extends from planning and designing capital works, construction and maintenance of on-ground assets, to engagement with the community (e.g. demand management).

Geolyse are a local multi-disciplinary consultancy firm who have worked closely with Council since 2007 to deliver secure and sustainable water supplies for Orange.

Department of Industry Water is responsible for the management of the surface water and groundwater resources across NSW. Approval is required from Department of Industry Water for harvesting water from waterways.

NSW Health provided advice on water quality risk management.

Project Outcomes

Cities as water supply catchments

  • Solutions harness the power of large impervious surfaces in urban environments for generating more reliable water supplies
  • Up to 25% of drinking water in Orange can be supplied by stormwater harvested from the urban areas.
  • 29% of drinking water can be replaced with treated stormwater via dual water systems in homes in Ploughmans Valley and North Orange

Cities providing ecosystem services

  • Creation of 4 stormwater treatment wetlands which slow and treat stormwater flows as well as provide important urban habitat
  • Peak flows reduced in creeks reducing risk of erosion
  • Conversation of weedy drainage corridors into constructed wetlands has created high amenity landscapes which are now valued by the community

Cities comprising water sensitive communities

  • Community engagement programs built confidence and support of stormwater harvesting schemes to supply drinking water
  • Extensive engagement with residents with dual water systems has built an understanding of the fit-forpurpose use of stormwater and drinking water in home
  • Signage is included in key infrastructure associated with the stormwater harvesting scheme to inform residents and visitors

Lessons Learnt

  • Be open to all options at the beginning
  • Helps to have management of the entire urban water cycle under one organisation
  • Need to be nimble and adaptive in design and delivery
  • Leadership and a good team is critical
  • Water assets can provide multiple outcomes

Project Cost



2008 - 2015


CRC for Water Sensitive Cities