Question to the Department for Business, Energy and Industrial Strategy:

To ask the Secretary of State for Business, Energy and Industrial Strategy, how many water mills there are in the UK in (a) total, (b) fully working condition, (c) need of repair and (d) need of full rebuilding.

The Government does not keep data on water mills.

The majority of hydro capacity in Great Britain was installed in Scotland in the first hydro revolution in the 1950s, with a smaller amount installed in Wales. The majority of these installations are still operating. In 2015, it was estimated that there were 1,065 operational plants with a capacity of 1,750 Megawatts, generating 6 Terawatt hours (equivalent to 1.8% of UK electricity supply)[1].

The Government does not monitor the condition of existing hydro power plants in the UK. It is a business decision for companies to determine when to carry out repairs and refurbishments.

[1] www.gov.uk/government/statistics/regional-renewable-statistics