Work has started to drain out a well-known reservoir in North Down – raising fears of its impact on wildlife which rely on it.
Northern Ireland Water has begun lowering the water level at Portavoe Reservoir, on the road between Bangor and Donaghadee, as part of a 10-week project to carry out essential maintenance when it is completely empty.
But dog walkers and wildlife enthusiasts – have expressed concerns about the impact on the surrounding habitat as the water level drops noticeably.
North Down councillor Austin Lennon questioned the timing of the project which he said was clashing with breeding season.
"There was a vast expanse of shallow wading water where I have seen many nesting birds in the past. Their habitat is now destroyed and this is the breeding season surely this could have been done at a different time," he said.
The RSPB advises that work of this nature should not be carried out during the breeding season.
Concerns were raised recently after visitors to the beauty spot noticed that water levels had been dropping dramatically over a number of days. Fresh water clams were being exposed and left to die along the waters edge. Water levels have continued to drop and NI Water has confirmed it intends to drain the reservoir completely.
A spokesman said: "NI Water has been liaising closely with NIEA (Northern Ireland Environment Agency) on the draining of the reservoir and as such, put in place a detailed scour management plan to protect and mitigate upstream and downstream impacts of flora, fauna and water quality. NI Water also consulted DARD (Department of Agriculture), Rivers Agency and DCAL (Department of Culture) who currently lease it for fishing.
"Current water levels are not having a negative impact on fish in the reservoir, however, NI Water will continue to work closely with DCAL to ensure that as the level drops, fish removal will be suitably managed."
The work being carried out is to refurbish a valve at the reservoir which is described as essential health and safety maintenance.
The Belfast Telegraph visited the reservoir and found one visitor trying to move fresh water clams back into the water after their location became uncovered.
The woman, who gave her name as Trish, was obviously upset as she pointed out pools where fish had been cut off.
"I come down here all the time and have cried myself sore over what is being done to the wildlife here. It's a disgrace. I have contacted the authorities but no one seems to care," she said.
Dog walker David Williams said: "The valve is at the edge of the water. Why can't they isolate the area and do what they need to without disturbing the wildlife and killing fish? It's madness to drain the whole reservoir. They tell us to turn our taps off and they pour all this into the sea. It's wrong."
Just last year the reservoir suffered a kill resulting in a loss of over 350 fish, mostly trout, though perch, eels and roach were also caught up in the tragedy. Many of the dead fish were infected with lice and a fungus – but despite several leads, DCAL still isn't sure what caused the incident.
Upon completion, the reservoir will be refilled.