Water supply The reservoirs are fed by the following waters: River Lee Diversion River Lee Flood Relief Channel New River The Thames-Lee Water Main Water treatment After being stored in the above reservoirs the water is piped to the Coppermills Water Treatment Works to be treated. In 2006 a smaller water treatment works was also built at Chingford at the edge of the William Girling and King George V reservoirs. See also London water supply infrastructure Bomb Crater Pond (Walthamstow) References Thames Water reservoirs Reservoirs in London