In-line Leak Detection Assessment Service

Bristol Water is a key water supplier in the Bristol region of England, providing drinking water to around 1.2 million people. The company manages a vast infrastructure regulated by Ofwat, ensuring efficient and high-quality service. Committed to sustainability, Bristol Water continually invests in innovative technologies to enhance efficiency and reduce leaks. One such initiative involved assessing a suspected leak in a 100-year-old cast iron pipeline in Somerset, Southwest England, using the Aganova Nautilus system.This inspection took place on one day in July 2024, focusing on a pipeline that carries raw water through the Mendip Hills. Given the pipeline’s rural location, traditional leak detection methods were challenging, leading to the deployment of the advanced Aganova Nautilus system operated by the local SUEZ team.

Pipeline characteristics

The inspected pipeline section had the following specifications:

• Length: 6,695 meters
• Pipeline Diameter: 33 inches & 24 inches
• Water Speed: 1 m/s – 0.4 m/s
• Pressure: 1 – 6 bar
• Pipeline Material: Cast Iron

Inspection preparation & deployment

 

#1 Insertion

The Nautilus V2 was deployed through a DN150 gate valve at Bristol Water's facility. The SUEZ team mounted the Nautilus insertion system onto the gate valve and used a pressure chamber to insert the sphere without interrupting the service. The entire process took 37 minutes.

#2 Synchronizers

Eight synchronizers were installed along the 7 km pipeline to enhance accuracy, considering possible changes in velocity. Each synchronizer took approximately 10 minutes to install. Additionally, two checkpoints were set up to track the sphere’s progress along the route.

#3 Navigation

The Nautilus sphere was inserted at 14:09, detected at checkpoint 1 at 14:13, and at checkpoint 2 at 15:50. The tracking system estimated the time of arrival (ETA) at 16:10, resulting in a total inspection time of 2 hours, given the flow conditions of 312 liters per second.

#4 Extraction

The extraction took place at Bristol Water waterworks. The SUEZ team mounted the Nautilus extraction system onto a DN150 gate valve, using a pressure chamber to retrieve the sphere without interrupting the service. This process took 1 hour, with the sphere extracted at 16:50. The disassembly of the extraction system to retrieve the sphere took an additional 25 minutes.

Results

After retrieving the Nautilus sphere, the collected data was sent to the data analysis department in Málaga, Spain. A final report was delivered to Bristol Water a week later, revealing three incidents, including one major leak.

The major leak was located downstream near the extraction point at Bristol Water’s Blagdon waterworks. Exact coordinates were provided to the client through Nemo, the digital platform. The Nemo AI algorithm estimated the leak’s flow rate upto 32.59 m³/hour, classifying it as a significant leak.

Additionally, the upgraded Nautilus 2 sphere enabled the delivery of a detailed pressure and altitude profile of the inspected pipeline section.

Conclusion

The Nautilus system successfully identified and located a major leak in the 100-year-old cast iron pipeline, demonstrating its effectiveness in challenging environments where traditional leak detection methods might fail. The successful deployment and retrieval of the Nautilus sphere, along with accurate data analysis, provided Bristol Water with actionable insights to address the identified leaks, ensuring the continued efficiency and sustainability of their water supply infrastructure.

This project demonstrates the level of cooperation and commitment of the teams from SUEZ, Aganova and Bristol Water to achieving significant water savings.