Across the world, critical water infrastructure is steadily ageing, buried out of sight and often overlooked. An important French regional drinking water provider, responsible for supplying around 310,000 consumers, was not prepared to wait for issues to surface before taking action.
A Non-Redundant Pipeline with Unknown Condition
A key component of the utility’s drinking water network is a DN900 ductile iron transmission main. This pipeline is a non-redundant link in their system, and if it failed, maintaining water supply would be extremely challenging.
The pipeline’s advanced age and criticality made collecting reliable condition data imperative. Soil conditions along the route were not fully documented, pressure transient data was limited, and there was no historical data on corrosion. As a result, the utility had a limited understanding of the pipeline’s structural health.
Robotic Inspection and Advanced Analysis
To close the knowledge gap, the utility partnered with Xylem for an advanced inline inspection. The team used PipeDiver, a free-swimming robot, to inspect the main without disrupting supply.
The PipeDiver mission lasted around 11 hours. During that time, the tool travelled approximately 22 kilometres through the transmission main, collecting detailed measurements of pipe wall thickness, out-of-roundness, and other potential threats with its ultrasonic sensors.
This data was analysed using advanced engineering techniques, including structural modelling and finite element analysis, to evaluate how identified defects would affect the pipeline under real operating conditions.
Targeted Repairs and Better Risk Management
The inspection revealed 697 areas of corrosion with pipe wall loss along the transmission main. However, the engineering analysis showed that only five pipes required immediate intervention.
With a clear understanding of the pipeline’s condition, the utility was able to adopt a targeted repair strategy, focusing maintenance where structural risk was highest while avoiding unnecessary large-scale replacement.
A Shift Toward Proactive Asset Management
Beyond immediate repairs, the project enabled the utility to move from reactive risk mitigation to proactive, data-driven asset management.
“This operation is fully in line with our patrimonial management approach. It allows us to guarantee the long-term reliability of our infrastructure, to limit the risk of service disruptions and to optimize the planning of our future renewal works.”- Arnaud Bechennec, Deputy Director in charge of operations SPL Eau du Ponant
The inspection results now serve as a baseline for future monitoring, and the utility has implemented a planned re-inspection cycle every two to three years. This proactive strategy bolsters confidence in the pipeline’s ability to provide reliable water service while helping the utility plan for the asset’s future.
