High-powered jet tanker will clear Hertfordshire's sewers

The new high-pressure jetting and vacuumation tanker will operate across the county, as well as London, Berkshire, Buckinghamshire, Oxfordshire, and parts of Surrey, Hampshire, Wiltshire, and Gloucestershire.

It costs £430,000 , and has the additional water jetting power needed to blast concrete from the inside of a sewer, preventing the need for a costly and time-consuming excavation to replace a blocked pipe.

Thames Water has become increasingly concerned about the instances of concrete, and other difficult-to-remove materials, causing sewer blockages that can disrupt services for hundreds of wastewater customers at a time.

In February 2017, it had to begin a major civil engineering project to remove a 10-metre section of main sewer under Hanover Park, Peckham, South London, which was found to be completed filled with concrete.

Other construction materials, such as mortar, grout and mastic can get into drains and sewers. Once solidified, they create snagging points for other materials wrongly disposed of down drains, such as wet pipes and sanitary products.

The problem may only be discovered during periods of heavy rainfall, when the restricted flow in the sewer results in localised flooding.

Andy Brierley is a director of Lanes Utilities, part of Lanes Group plc which is the wastewater network maintenance partner for Thames Water.

He said: “In some cases, builders accidently pour concrete and other materials down drains and sewers, but in others it appears to be a deliberate act to avoid the need to dispose of it legitimately.

“While our Thames Water colleagues are escalating their legal response to such irresponsible actions, we realised we needed a new weapon in our armoury to tackle these extreme blockages.

“By their very nature, these blockages can be devastating for whole communities. One moment a large sewer can be flowing freely, the next it can be completely blocked, or flooding, inconveniencing thousands of wastewater customers.”