Written question WQ93683

The legal framework for reservoir safety is the Reservoirs Act 1975, with amendments from the Flood and Water Management Act 2010. This legislation was established to minimise the risk of damn failure and the subsequent flood risk. It only applies to large, raised reservoirs which are designed or used for collecting and storing 10,000 cubic metres of water or more, above the natural level of the surrounding land and includes artificially raised lakes.

Under the Reservoirs Act, reservoir owners (‘undertakers’ in the language of the Act) have ultimate responsibility for the safety of their reservoirs. Undertakers are required to implement specific safety measures, such as appointing qualified civil engineers to supervise activity at the reservoir at specific points during the reservoir’s lifetime. Any associated costs are also borne by the undertaker – be that a private sector or public sector undertaker.

Meanwhile, Natural Resources Wales (NRW) is the regulatory authority that oversees reservoir safety compliance in Wales. As the regulatory authority, NRW’s principal duty is to ensure reservoir undertakers observe and comply with the Reservoirs Act. Where owners do not comply with their duties under the Act, NRW has a range of powers from providing advice and guidance and issuing warning notices, to acting in default and appointing appropriate engineers or undertaking necessary works to maintain safe operation of the reservoir, and seek to recharge these costs. Where a reservoir undertaker cannot be identified, NRW can also use its regulatory powers to step in and take necessary safety measures. In such cases, NRW works with Welsh Government to agree budgetary needs.