 Water for treatment and use is drawn from the reservoirs through the valve towers and delivered to the aqueduct to flow south-east to several water treatment works.The Metropolitan Water Board operated the reservoirs until the Board was abolished in 1974 under the provisions of the "Water Act 1973" and ownership and control transferred to the Thames Water Authority, now Thames Water.In 1992 there was a proposal to increase the capacity of the reservoirs by raising the height of the dam walls and removing the dividing embankment.