Wessex Water has used pioneering robot technology as part of a trial to explore alternative cleaning methods in hard to reach water stores. Using remote control engineers guided the submersible machine – known as the VR600 - around the bottom of the service reservoir, which holds water underground.

Wessex Water supply manager Chris Muscat said the company routinely surveyed and cleaned reservoirs but completing this work normally involved draining the site to allow cleaning teams inside. He said:

 “Our normal process of reservoir cleaning can take anything up to two weeks while we drain, clean and refill the tank.

“It can be a costly, time consuming process which sometimes raises a risk of disruption to customers’ supplies.

“But the robot can clean the reservoir in a couple of days while it stays 'in service', meaning water stored there can be safely sent to customers while work takes place.”

The state-of-the-art device was meticulously cleaned and disinfected before the trial so it could be safely placed into the water. Once submerged it used a system of rotary brushes and a powerful suction pump to clean the floor of the reservoir.

At the same time an onboard camera and powerful lights allow engineers to monitor the cleaning process, which is recorded on a DVD for future reference. A smaller ROV robot was also used to carry out a routine inspection of the reservoir to check for structural damage.

Mr Muscat added:

“This successful trial means our customers in Melksham will continue to receive top quality water. We are now considering using the robot at other reservoirs in Wiltshire and across the company area where our normal cleaning process proves especially difficult.”

The robots are operated by water quality engineers Panton McLeod.

Paul Henderson, operations director at Panton McLeod, said:

“Our underwater robots are state-of-the-art machines and play a vital role in the work we carry out for major water companies across the UK.

"We were delighted with how the trial went and we now look forward to working with Wessex Water again in the future.”

The service reservoir near Melksham is one of almost 400 in the Wessex Water region. The large underground tank has a maximum capacity of 2,500,000 litres and provides water to around 2,000 properties in and around Melksham.