Water Mains Leak Detection in Didcot

Symptoms

With livestock water troughs, stable supplies, and garden tap pipework all drawing from the same system, isolating the cause required a methodical approach. A water mains leak detection survey was the appropriate response given the scale of the site and the multiple potential leak points across buried and surface-level pipework.

The meter continued to register usage even with no deliberate draw on the system, confirming an active, uncontrolled loss somewhere on the supply network.

Methods Used

Given the size of the site and the number of supply branches — troughs, stables, barns, and garden taps — the investigation began with a full visual inspection of all 20 water troughs before moving to acoustic and tracer gas methods for buried pipework. This combination is well-suited to water mains leak detection across agricultural properties where supply lines run underground between structures and may not have been accessed in years.

Acoustic listening was used to survey pipework runs, and tracer gas testing identified a high reading at a hidden valve chamber serving the water troughs. The chamber was excavated to expose the stop valve, which was found to be leaking and was repaired on site.

Post-repair monitoring then revealed a further leak on a garden tap supply pipe, which was isolated after the customer confirmed the tap was no longer required.

Investigation Process

1. 1
   Visual inspection of all water troughs

   All 20 water troughs were inspected. Three minor leaks were found on fittings; the customer arranged for their own plumber to repair these.

2. 2
   Acoustic and tracer gas survey of buried pipework

   A listening stick was used across the supply network, followed by tracer gas testing. High gas readings were detected at a hidden valve chamber serving the water troughs.

3. 3
   Excavation of valve chamber

   Chamber sections were removed to expose the stop valve. A leak was confirmed on the stop valve, which was repaired on site.

4. 4
   Post-repair meter monitoring

   Following the stop valve repair, the digital water meter continued to register usage, indicating at least one further leak remained active on the system.

5. 5
   Leak identified on garden tap supply pipe

   Further investigation located a leak on the supply pipe to a garden tap. The customer confirmed the tap was no longer in use, so the pipe was isolated.

6. 6
   Ongoing meter anomaly identified

   After all known leaks were addressed, the meter was still recording approximately 1 litre every 10 minutes, with flow appearing to move both forward and backward — indicating either a faulty meter or a missing check valve.

7. 7
   Recommendation to contact Water Board

   The customer was advised to contact the Water Board to inspect or replace the digital meter and to consider installing a check valve to prevent backflow and ensure accurate readings.

Result & Outcome

Two active leaks were located and resolved during the visit: a leak on a stop valve inside a buried chamber serving the water troughs, and a leak on the supply pipe to a disused garden tap. The stop valve leak was repaired directly; the garden tap supply was isolated at the customer's request. Three further minor fitting leaks on the water troughs were identified visually and referred to the customer's own plumber.

Despite these repairs, the meter continued to show a residual reading of around 1 litre every 10 minutes, with the unusual behaviour of flow appearing to register in both directions. This is not consistent with a live supply leak and points instead to either a faulty digital meter or the absence of a functioning check valve — neither of which falls within the scope of a water mains leak detection survey to resolve.

The site was left clean, safe, and tidy. The customer has been advised to contact the Water Board to investigate the meter and consider installing a check valve. All confirmed leak sources on the private supply network have been dealt with.