Advanced Sewer Depth Monitoring Programme
HWM Global supports Thames Water in the delivery of an ambitious Sewer Depth Monitoring (SDM) installation programme which saw almost 4,000 advanced level sensors installed in a single year.
Thames Water manages one of the most complex sewer networks in the UK, carrying billions of litres of wastewater every day. With tens of thousands of blockages putting increased strain on ageing pipes, the utility needed a smarter SDM solution for detecting issues before they escalate.
Every day, more than 15 million people across London and the Thames Valley generate 4.6 billion litres of wastewater all flowing through Thames Water’s complex 68,000-mile sewer network. With rising populations and more extreme weather patterns adding pressure, keeping the system flowing is critical.
Water companies face various challenges associated with pipe blockages. On average, Thames Water clears 75,000 blockages a year, spending £18 million to remove approximately 30 tonnes of material from just one of its sewage works every day. When left unmanaged, these blockages can cause flooding in customers’ homes and businesses.
“We get thousands of entirely avoidable blockages on our sewers each year… we’d urge everyone to help by only flushing the 3Ps – pee, poo and paper…to help keep the sewers flowing and prevent them blocking and backing up into people’s houses and gardens, or even into the local rivers”
Anna Boyles, Performance, Risk and Optimisation Manager, Thames Water.
To gain early visibility of developing issues, Thames Water installed 3,7000 non-contact level sensors as part of their sewer depth monitoring programme. Using advanced sewer-level technology paired with Intelligens WW data loggers, the system provides continuous level measurement and rapid data transfer.
Non-contact sensing technology significantly reduced maintenance requirements, while Intelligens WW offers flexible configuration, advanced telemetry, and reliable data delivery. Its long-life battery powers both the logger and the level sensor, without the need for additional battery packs and reducing install complexity.
In choosing to install this SLM solution, Thames Water has selected an effective early warning system. Should levels rise, automatic alarms alert operational teams to potential blockages, enabling faster intervention and helping to prevent flooding and pollution incidents.
HWM Global is proud to support Thames Water in this ongoing programme to strengthen network resilience and reduce the impact of sewer spills across one of the UK’s largest wastewater systems.
