Southern Water’s AI-enabled smart sewer system led to more than 4,000 interventions in the past year, enabling its teams to remove blockages.

Blocked sewers are the single biggest cause of pollution incidents – from manholes spilling into streams, gardens filling with sewage and internal flooding where sewers back up and pour into sinks, showers and loos.

Around 34,000 sewer lever monitors allow the water company to constantly check on flows and spot anything out of the ordinary which might highlight a blockage or leak.

The commonest cause of blockages is flushed wet wipes along with cooking fat, oil and grease tipped down the sink instead of properly disposed of.

Since last April, Southern Water has also dealt with 47 instances of roots puncturing or blocking pipes - a known cause of blockages – although this is dwarfed by 1729 caused by wet wipes and other ‘unflushables’.

A recent example in Whitstable saw a blockage detected by the AI-enabled smart sewer system caused by root infiltration forming in a pipe - left unchecked, the manhole would have overflowed with sewage.

Daniel McElhinney, Proactive Operations Control Manager at Southern Water, said:

“Our smart sensors measure the level of sewage flowing under manholes in blockage hotspots. However, the real innovation is how machine learning or artificial intelligence, learns the normal behaviour of sewers and can tell the difference between morning and evening rushes, rain in the system and a blockage forming.

“Instead of turning up after the event to clean up and commiserate with devastated customers, we’re spotting hundreds of potential blockages before it’s too late so our teams can scramble round with high pressure water jets to clear the sewer.”

After detecting sewer blockages, Southern Water teams also call round the neighbourhood to tell them about close calls and educate them on how to keep sewers flowing freely.