Queen Mary Reservoir

The Queen Mary Reservoir lies in Spelthorne, Surrey, just south of Ashford and east of Laleham. It covers 286 hectares and stands 14 metres above the surrounding land. The M3 motorway passes within 400 metres to the northwest, while Heathrow Airport lies 6 kilometres north. The reservoir was built on land transferred from Middlesex to Surrey in 1965 and 1974. It was once the world’s largest reservoir when completed in 1925. The reservoir was designed by Henry Stilgoe for the Metropolitan Water Board and opened by King George V. During the Second World War it tested a submersible nicknamed Sleeping Beauty. In 2010 Prince Philip unveiled a replica of the craft at Eden Camp museum. The embankment uses a puddle clay core and slopes at one in three to hold back the water. A 1-kilometre breakwater of gravel and earth runs north–south to calm the surface. Visitors find a wide expanse of water ringed by grassy banks and designated for nature conservation. The Queen Mary Sailing Club operates on the western shore, offering training and boat hire. A jetty and aggregate facility stand on the west side, where sand and gravel were once removed. Water enters via the Laleham Aqueduct and leaves through an outlet tower near the north-east bank. The varied bird life attracts observers across 360 hectares of protected land.