Llyn Anafon: Ecological assessment of the aquatic flora to support HRA, 2017

Llyn Anafon lies within the Eryri SAC, North Gwynedd, Wales (500 m amsl). Originally a natural lake, the level was raised by approximately 1.5 m in 1929 to provide potable water. Although now out of active commission for water supply, the site owners Dwr Cymru / Welsh Water (DCWW) maintain the responsibility for the dam and the site remains within the jurisdiction of the Reservoirs Act 1975. Deterioration of the retaining dam resulted in the most recent Section 10 report to conclude that the risk of failure exceeded acceptable levels and that a long-term solution is required in the interests of public safety. This report triggered DCWW to consider a series of engineering options ranging from full repair to complete removal of the dam, with decommissioning being the favoured plan for the long-term sustainability and safety of the site