The ACT Non-potable Water Master Plan has been developed around the need to diversity the ACT's water supply under a hotter and drier climate. A strategy built around diverse water sources and a mixed water infrastructure would provide the flexibility to access a portfolio of water sources at least cost, with costs to include environmental impacts and other externalities.

So while the Cotter Dam enlargement and Murrumbidgee to Googong Pipeline project will increase the security of potable water supply, the Master Plan focuses on alternative water sources. These alternative sources include:

1. Using recycled water from sewage treatment plants
2. Using urban harvested stormwater from wetlands

By using alternative sources, nutrients are returned to public open space via irrigation rather than into downstream rivers where they have a negative effect. By implementing the strategy, 2.8 tonnes of Total Phosphorus and 25.3 tonnes of Total Nitrogen would be intercepted.