The use of sonar technology for sewer inspections is on course to save Thames Water more than £1m a year.
Lanes Group is claiming to be the first utilities contractor in the UK to commercially deploy pipe inspection technology that uses sound to assess the condition of sewers.
The company is working with Thames Water using the SewerBatt acoustic inspection device, which uses the same echo-location principles that bats use.
The SewerBatt inspection programme has been in operation across the Thames Water region since the start of May, following an 18-month development and trial phase.
For planned sewer maintenance, the technology is already reducing the number of CCTV drainage surveys required by 33%. The target is to reduce overall CCTV costs by £1.2m per year.
Lanes Utilities managing director Conrad Ashby said: “SewerBatt has significant benefits in terms of improving the overall operational efficiency and sustainability of our underground investigations. It allows us to identify blockage and pollution issues in drainage assets much more quickly than with traditional methods.
“It provides a more cost-effective solution to proactive management of the sewer system, through what is a quick and easy asset condition assessment technique. Faster, more energy-efficient and more effective responses to key environmental issues make this a powerful new tool for improving the sustainability of drainage services and systems.
The UK-designed and manufactured device works by sending multi-frequency sound waves along sewer lines. Their interaction with chambers, lateral connections, cracks, deformities or blockages sends unique echoes back to the device, which are displayed on a digital graph.
Within 30 seconds, the system’s software analyses the data from each length of pipe, and provides a simple output assessment of its condition as being green, amber of red. Green is clear, amber requires further analysis, and red denotes a problem that requires remedial action.
Lane’s trials, during which a CCTV drainage survey was carried out to back up each SewerBatt inspection, showed the system was 97% accurate.
SewerBatt has also been used by Yorkshire Water and Scottish Rail but Thames Water has become the first UK water company approve its commercial deployment. The devices are being used on programmes of work to support with planned maintenance, pollution response, and blockage hotspots.
SewerBatt can be operated by one drainage engineer and is fully mobile. The sound transmitter and receiver are attached to a carbon fibre pole, which is lowered into sewer pipe via drainage manholes. The survey results and data are transmitted from a laptop computer to Lanes Group’s HQ in Slough, where they are viewed by an analyst, and decisions are made on what further action is required.
Lanes project manager Dean Hansford said: “The device can be used to inspect pipes with diameters from 100mm to 600mm, and up to 230m in length. We are expecting each operator to survey up to a kilometre of sewer pipe a day.
“A SewerBatt inspection costs significantly less than a CCTV drainage survey. For planned maintenance, 33% of all inspections are coming back green. Previously, all those would have had a CCTV survey. There are also a lot of powerful ways we can combine SewerBatt data with other mapping data to help us monitor and analyse the condition of the sewer system. The technology is very new. But it has huge potential.”
