<Tr> <Th> Islands </Th> <Td> </Td> </Tr> <Tr> <Th> Sections / sub-basins </Th> <Td> Bakethin Reservoir </Td> </Tr> <Tr> <Td_colspan="2"> Shore length is not a well - defined measure . </Td> </Tr> <P> Kielder Water is a large man - made reservoir in Northumberland in North East England . It is the largest artificial lake in the United Kingdom by capacity of water and it is surrounded by Kielder Forest, the biggest man - made woodland in Europe . The scheme was planned in the late 1960s to satisfy an expected rise in demand for water to support a booming UK industrial economy . But the decline of traditional heavy industry, together with more water - efficient industrial processes and better control of water supply leakage, served to undermine the original justification for the reservoir and many came to criticise the government - funded project as a white elephant . </P>

Why is there a tunnel under kielder reservoir