 Inspections in 2005-07 identified that this was inadequate, and proposed that the drawdown should be 1.0 m/d as defined in the provisions of the "Reservoirs Act 1975" (c.23).This was achieved by installing twin 1.2 m diameter siphon pipes over the embankment.The valves controlling the outflow are 8.0 m high and have a flow capacity of 7 m3/s.