Sewer sounding

An acoustic monitoring system will allow engineers to rapidly identify blockages and damage in sewer pipes.

Professor Kirill Horoshenkov from Bradford University is developing an acoustic monitoring system that will allow engineers to rapidly identify blockages and damage in sewer pipes.

The key elements of the acoustic system are a small multi-sensor array and an advanced, real-time signal processing algorithm which overcomes the effects of ambient noise and reverberation in the sewer environment.

Water companies in the UK are legally required to maintain the condition of their sewer systems and to reduce flooding incidents.

Consequently, monitoring pipes for obstructions and defects forms an important part of the operational and maintenance costs.

'Existing sewer survey methods are limited to the interpretation of CCTV and Lightline images, which are relatively slow,' Prof Horoshenkov said.

Such CCTV surveys take between two and four hours per 100m length, and a similar amount of time for image analysis.

For this reason, less than 2 per cent of the UK network is surveyed every five years.

This week, Professor Horoshenkov won a £155,000 Brian Mercer Award for Innovation from the Royal Society, which will allow him to further develop his acoustic system, potentially reducing the measurement and analysis time to tens of minutes per 100m of sewer pipe.

This would enable operators to survey more of their network more frequently, allowing better monitoring strategies to be developed, and earlier identification of defects and blockages, leading to fewer flooding incidents and better-planned maintenance.