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A review of investment decisions at small drinking water supply systems with declining water quality issues

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Since 2002 Scottish Water, supported by the Scottish Government, has successfully delivered a capital investment program which has brought about measurable improvements to drinking water quality and service levels across Scotland aimed at delivering compliance with the Water Scotland Act, and reducing risks of non-compliance. While the vast majority of treatment systems deliver cost effective drinking water, there remains a sub-set of drinking water treatment works that have challenges that are manifested as either deterioration in drinking water quality and/or require intensive capital investment to mitigate the stress on drinking water quality compliance at small rural treatment works. Investment drivers typically include DOC, Fe, Mn, turbidity, cryptosporidium and disinfection control. 

This project seeks to review the challenges in delivering drinking water compliance, with focus on the investment drivers listed above. The research will include the identification of three case studies - small drinking water supply systems with declining water quality issues - and an evaluation of the capital investment decisions made which are designed to meet drinking water regulatory compliance with a view to establishing value for money, sustainability, improvements to public health, improvements to social justice aspects, effectiveness of interventions, and how the decisions made have been influenced by the regulatory and policy framework.

Project Objectives

1. In collaboration with the CREW Protecting Drinking Water steering group, identify three case study sites.

2. Review the drinking water treatment system’s performance relative to the drinking water regulatory requirements and the legislative framework.

3. Assess the capital investment plans to improve compliance at the case study sites and investigate the effectiveness of the decisions in relation to the supplies, interventions and cost effectiveness of the interventions proposed.