Report lists important factors in indirect water reuse

Utilities considering “purple pipe” non-potable water-reuse schemes should be aware of a number of important factors which could influence their decision, an upcoming report from the WateReuse Research Foundation (WRRF) will say.

It also points out that acceptance of potable reuse is expected to grow considerably over the coming decade or two, and in many cases will provide a more cost-effective and efficient way of augmenting supply.

The WRRF published an executive summary on 2 October 2012 prior to the full publication later this year of The Future Of Purple Pipes: Exploring The Best Use Of Nonpotable Recycled Water In Diversified Urban Water Systems (WateReuse-10-14).

The report’s authors surveyed 15 Australian and 14 US utilities in compiling the research, and a number of case studies will be presented that explore in greater detail the issues associated with regulatory approvals and ongoing operations. Studies will be presented for Australia (Sydney Water, Allconnex Water, City West Water) and the US (Tucson Water and Denver Water).

Factors meriting careful consideration, the report says, include:

  • Regulatory approvals
  • Take-up rates
  • Demand variations
  • Funding arrangements
  • Managing the risks of cross-connections.
  • Unless these matters are fully considered, then proponents may not realize the level of benefit intended from these schemes, the report concludes.