Table of contents

• Drinking Water 2025 - Private water supplies in England
• Introduction
• Enquiries
• Data return findings
• Case studies

Case studies

The Inspectorate publishes a variety of case studies on private water supplies on its website. These cover a range of scenarios and subjects, which are largely derived from enquiries to the Inspectorate, either from local authorities or private water supply users. Some come from third parties, including lawyers, agencies, local councillors and ministers.

These case studies show and share the range and diversity of issues and circumstances that can come about in relation to private water supplies. The additional benefit of their publication on the Inspectorate’s website is to make available the learning that can be taken from them.  

There were eight case studies compiled in 2025. These can be found on the website at Drinking Water Inspectorate (dwi.gov.uk): 

• A public supply that switched to being a private water supply 

• Hospital case revisited 

• Purchasing a property served by a private supply 

• Deficiencies in proactive risk assessment on a regulation 9 supply 

• Registration of private water supplies 

• Nitrate risks on a private water supply 

• Identification of a regulation 8 supply during a water quality event 

• Applying a risk-based approach to investigate the cause