Scheme to improve flood safety at Eryri reservoir gets thumbs up

Dale Spridgeon, Local democracy reporter.

Essential safety work to protect against the potential flooding of an Eryri reservoir during major weather events has been given the green light.

The refurbishment and installation of a new siphon system at Llyn Mair, part of the historic park and garden site, Tan Y Bwlch at Maentwrog, was agreed with conditions by Eryri National Park’s planning authority.

Officers said that although the work was considered “essential”, it was not “major,”  at a meeting of the planning and access committee on Wednesday, February 25.

“The proposed works are to provide a siphon, so that the Llyn Mair reservoir is better equipped to deal with major weather events, so it is possible to safely lower the level of the reservoir,” the meeting was told.

Officer Aled Lloyd described, using slides, how it was in an area with a 1% – or one in 100 – chance of flooding from rivers in a given year, including the effects of climate change.

He added: “Given the  proposal has been designed to ensure greater safety in a major weather event, officers are satisfied there is justification for the proposal and that it accords with policy.”

He said the siphon would be located partly inside the reservoir and partly inside the original reservoir spillways: “Therefore, it will not alter the way that this historic park and landscape will be experienced, understood and appreciated.

“There will be no visual, significant impact on the area and no impact on the Listed Plas Tan Y Bwlch historic park and garden or on the historic universal value of the World Heritage Site.”

Having considered all relevant material planning considerations, including local and national planning policy and guidance, it was considered that the proposal was “acceptable” and a recommendation to approve was given.

In a vote, the application was agreed, with conditions, including an environmental plan for the work to be carried out, to assess its impact.