Artificial Intelligence installed by Southern Water beneath a West Sussex community’s feet saved homes from flooding when a fatberg formed.

Residents of East Lavington, near Petworth, were put at risk by the buildup of fat, oil, grease and other ‘unflushables’ in a sewer - but thanks to Southern Water’s system of digital sensors, the company’s teams were able to tackle the blockage before it could cause gardens and homes to flood with wastewater.

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

Thanks to around 32,000 sewer lever monitors, Southern Water can now constantly check on flows and spot anything out of the ordinary which might highlight a blockage or leak.

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

“The sensors measure the level of sewage flowing under manholes in blockage hotspots, but the real innovation is how machine learning or artificial intelligence learns the normal behaviour 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.”

Most customers do not realise the average suburban sewer is only the diameter of an orange or a tennis ball. It doesn’t take much cooking fat to combine with other ‘unflushables’ such as wet wipes or even ear cleaning sticks, to form a fatberg.

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