Advanced Leakage Detection Helps Essex and Suffolk Water New Pipeline

Essex & Suffolk Water had installed a new 7.9 km DN800 raw water main to increase capacity and improve resilience at Langford Water Treatment Works. However, despite multiple pre-commissioning pressure tests and extensive investigations using conventional leak detection methods, the pipeline continued to fail testing.

 

With no visible signs of leakage and a predominantly rural route, identifying the source of the problem proved extremely difficult. As commissioning delays continued, Essex & Suffolk Water required a more accurate solution capable of locating hidden defects quickly and non-invasively

SUEZ's Leakage and Condition Assessment Team partnered with Aganova, the developer of the Nautilus® in-line acoustic inspection system, to investigate the pipeline. Nautilus® is a free-swimming acoustic sphere that travels through a live pipeline, detecting leaks and anomalies from within the asset without disrupting operations. On 27 August 2025, SUEZ deployed the technology across the entire 7,940-metre pipeline under an operating flow of approximately 680 m³/h. To maximise accuracy, the team installed multiple synchronisers and checkpoints along the route to track the sphere's progress and precisely locate any defects identified during the survey. The inspection was completed in a single day, with the sphere successfully inserted, tracked and recovered without interrupting service.

Analysis of the inspection data by Aganova and SUEZ identified five incidents:

• Two major leaks (F1)
• One medium-severity leak (F2)
• One minor leak (F3)
• One anomaly (A1)

consistent with an incipient leak The two major leaks alone were estimated to account for approximately 1 megalitre of water loss per day, clearly explaining the repeated pressure test failures.

 

Using the precise location data provided by Nautilus®, Essex & Suffolk Water was able to carry out targeted repairs and successfully resolve all identified defects. The pipeline subsequently passed commissioning requirements and was brought into service.

 

By combining SUEZ's leakage expertise with Aganova's innovative Nautilus® technology, the project delivered a rapid, accurate and cost-effective solution, enabling the successful completion of a critical water infrastructure asset where conventional approaches had failed.