Ultrasound warning serves its porpoise
By David Greenwood
2nd November 2004
A chain of tiny ultrasonic devices helped protect schools of playful porpoises during a major £3.5m construction project off the North Wales coast.
Experts were drafted in to devise a foolproof method to keep the inquisitive mammals at bay.
Welsh Water is trying to protect them while workers laid a kilometre-long marine outfall pipe, blasting through rocky areas, close to the entrance of Holyhead's Breakwater Country Park.
And after in-depth consultations with conservationists they homed in on a system of "marine pingers".
Welsh Water project manager Simon Cowan said: "We were told by the Countryside Council for Wales that porpoises and seals had been sighted in the area in which we were going to work.
"We wanted to protect them and installed the pingers. Once submerged they give off ultrasonic sound which can't be heard by humans but which can be picked up by the porpoises.
"It was enough to stop them from getting too close and getting harmed."
The outfall is a key part of the company's £35m scheme to upgrade its wastewater network in the Holyhead area.
Mr Cowan added: "The outfall is a significant achievement.
"As well as the challenging sea conditions we had to take into consideration the fact the surrounding headland and waters are special areas of conservation. “ We also consulted with the Stena ferry company, local harbourmaster, coastguard and local fishing and yachting groups and chose a construction method which involved drilling under the headland and 200 metres out to sea.
Colin Crumlin, managing director for contractors Galliford Try Construction, said: "The successful completion of the outfall was one of the most challenging phases of the scheme which is due to be completed by the end of next year."
According to Welsh Water it was designed to help protect the quality of coastal waters as well as helping attract new businesses to the area.