Non-potable Dual Pipe Water Reuse Systems and Risks to Water Quality Project

Research aims and objectives

Non-potable water reuse systems have become increasingly more popular and complex over the last three decades. These systems include the reuse of greywater (domestic wastewater excluding faecal matter and urine) and rainwater, that is either partially treated or not, for non-potable domestic use such as toilet flushing or garden irrigation via a dedicated distribution system. The aim of this research project is to review the current risks from such systems and the suitability of English and Welsh regulation to manage these risks and evolving systems. The primary focus will be on public non-potable water reuse systems operated via a separate dedicated non-potable water distribution system. Consideration will also be given to the impact of multiple individual private systems (e.g. for new housing developments or large commercial units).

The objectives will be to establish:

- What are the risks from non-potable dual pipe water reuse systems and how are these best controlled?

- Do the risks vary depending on the age of the systems? Are the risks of cross connections suitably mitigated in the short and long term?

- What are the regulatory controls for these types of systems and are they adequate to mitigate risk?

- What is the user/ owner perception of such systems?

- How sustainable are such systems as a whole life cost?

- Understanding the barrier to dual pipe reuse systems and whole life benefits vs other reuse options