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Comparison of Private water supply and public water supply ultraviolet (UV) systems - WT1298

Description
Drinking water supplied in England and Wales must be wholesome and safe to drink; this applies whether the water is a public or private supply.

A minimum treatment requirement is that all water supplies must be disinfected. Ultraviolet (UV) disinfection has been used for many years on both public and private supplies. If properly designed and maintained, UV disinfection will inactivate harmful microorganisms ensuring that water is safe to drink.

Regulatory sampling of drinking water shows greater than 99% compliance with microbiological standards on public supplies but only 93% compliance on private supplies. One factor affecting private supplies is believed to be inappropriate implementation of some UV systems.

The objective of this study is to understand and highlight the critical differences between UV technologies used on public and private supplies. This study aims to:
• Establish the range of UV technologies used on public and private supplies in England and Wales, and establish the critical differences in functionality and application.
• Review international standards for UV treatment systems to compare validation criteria and identify which criteria would demonstrate suitability for use in private supplies.
• Produce simple guidance for householders and local authorities to help in the selection and assessment of UV systems used in private supplies.

One outcome of this study may be pilot trials to establish the suitability and performance of the most common UV system(s) used on private supplies. This will elucidate issues with UV disinfection and in the longer term help to improve drinking water quality.
Objective
1. Establish the range of UV technology employed by water companies in England and Wales and establish the functionality and application.

2. Establish the range of UV technology employed by private suppliers in England and Wales and establish the functionality and application.

3. Establish the critical differences in functionality and application between UV technology used in public and private supplies in England and Wales.

4. Compare the different types of validation criteria for different UV treatment systems and their application across Europe.

5. Review British Standard for Water conditioning equipment inside buildings - Devices using mercury low-pressure ultraviolet radiators requirements for performance, safety and testing (BS 14897), and other European and World standards for UV treatment systems to identify which validation criteria would demonstrate suitability for use for a private water supply.

6. To produce a simple self-help leaflet to help households select a suitable UV system – to be published electronically.

7. To produce a simple guide to help local authorities assess the suitability of an installed UV system – to be published electronically.

8. Design a pilot study to determine the suitability / performance of the most common UV system(s).

Project Documents
• FRP - Final Report : DWI70-2-306   (1741k)
• EXE - Executive Summary : DWI70-2-306exsum   (107k)
Time-Scale and Cost
From: 2015

To: 2016

Cost: £78,920
Contractor / Funded Organisations
WRc plc
Keywords
Drinking Water              
Water Quality              
Water Supply              
Fields of Study
Water Quality