| Staines Reservoirs | |
|---|---|
 Stanwell and the Staines Reservoirs in 2011 | |
  Staines Reservoirs | |
| Location | Surrey |
| Coordinates | 51°26′49″N 0°29′12″W / 51.44694°N 0.48667°W |
| Type | reservoir puddle clay embankment |
| Primary inflows | 295,496 cubic metres/day |
| Primary outflows | 364,000 cubic metres/day |
| Catchment area | River Thames |
| Basin countries | United Kingdom |
| Built | 1902 |
| Surface area | 172 ha (430 acres) |
| Average depth | Dam walls 6.4–10.67 m (21.0–35.0 ft) high |
| Water volume | 15,175,000 m3 (535,900,000 cu ft) |
The Staines Reservoirs are two large pumped storage reservoirs sitting to the east of the King George VI Reservoir near Heathrow airport in Surrey within the Colne Valley regional park. The village of Stanwell is mainly to the north east, and the town of Staines is to the south.
Both adjoin, west, the A3044. The south one adjoins the A30 where the road is bypassed by the intra-M25 motorway network but is a trunk road, maintained by National Highways. They were completed in 1902.[1]