The Queen Mary Reservoir is one of the largest of London's reservoirs supplying fresh water to

London London is the capital and largest city of England and the United Kingdom, with a population of just under 9 million. It stands on the River Thames in south-east England at the head of a estuary down to the North Sea, and has been a majo ...

and parts of surrounding counties, and is located in the Borough of

Spelthorne Spelthorne may refer to: * Borough of Spelthorne, a local government district in the county of Surrey, England * Spelthorne (UK Parliament constituency), Surrey constituency in the British House of Commons * Spelthorne College, was a single-cam ...

Surrey Surrey () is a ceremonial and non-metropolitan county in South East England, bordering Greater London to the south west. Surrey has a large rural area, and several significant urban areas which form part of the Greater London Built-up Area. ...

. The reservoir covers and is above the surrounding area.

Location

Queen Mary Reservoir is located south of Ashford and east of Laleham. It lies south of the A308 and at its closest point northwest of the M3 motorway. Heathrow airport is 3.7 miles north of the reservoir. The reservoir was formerly designated as being in the county of

Middlesex Middlesex (; abbreviation: Middx) is a Historic counties of England, historic county in South East England, southeast England. Its area is almost entirely within the wider urbanised area of London and mostly within the Ceremonial counties of ...

. In 1965 Staines and Sunbury-on-Thames Urban Districts were transferred to the county of Surrey. The Borough of

was formed in 1974 incorporating Staines and Sunbury-on-Thames Urban Districts. The reservoir is now designated as part of the county of Surrey.

History

Construction of the Littleton Reservoir was authorised under the provisions of the ''Metropolitan Water Board (Various Powers) Act 1921'' (11 & 12 Geo. 5, c.cxv). It was designed by the Board’s Chief Engineer Henry Stilgoe (1867-1943) and was completed in December 1924. Some sources state that the reservoir was designed by

John Watson Gibson Sir John Watson Gibson (9 August 1885 – 19 March 1947) was an English civil engineer. He designed dams in England and in Anglo-Egyptian Sudan and port installations in England and Ireland. In the UK he is most notable for having designed a k ...

for the

Metropolitan Water Board The Metropolitan Water Board was a municipal body formed in 1903 to manage the water supply in London, UK. The members of the board were nominated by the local authorities within its area of supply. In 1904 it took over the water supply functi ...

. It was formally opened by King George V in June 1925 as the Queen Mary Reservoir, renamed for the Queen Consort,

Mary of Teck Mary of Teck (Victoria Mary Augusta Louise Olga Pauline Claudine Agnes; 26 May 186724 March 1953) was List of British royal consorts, Queen of the United Kingdom and the British Dominions, and Empress of India, from 6 May 1910 until 20 Janua ...

; a plaque commemorates the event. It was the largest reservoir in the world at that time. In 1943, during World War II, the reservoir was used for testing submersibles. The submersible was nicknamed "

Sleeping Beauty ''Sleeping Beauty'' (french: La belle au bois dormant, or ''The Beauty in the Sleeping Forest''; german: Dornröschen, or ''Little Briar Rose''), also titled in English as ''The Sleeping Beauty in the Woods'', is a fairy tale about a princess cu ...

". In 2010

Prince Philip Prince Philip, Duke of Edinburgh (born Prince Philip of Greece and Denmark, later Philip Mountbatten; 10 June 1921 – 9 April 2021) was the husband of Queen Elizabeth II. As such, he served as the consort of the British monarch from E ...

visited the reservoir to unveil a modern replica of the submersibles tested here. The model is on display at the

Eden Camp museum Eden Camp Modern History Museum is a large Second World War-related museum near Malton in North Yorkshire in England. It occupies a former Second World War prisoner-of-war camp of 33 huts. After the prisoners left, the camp was used for stora ...

near Malton,

North Yorkshire North Yorkshire is the largest ceremonial counties of England, ceremonial county (lieutenancy area) in England, covering an area of . Around 40% of the county is covered by National parks of the United Kingdom, national parks, including most of ...

Structure

The reservoir embankment has a

puddle clay Puddling is both the material and the process of lining a water body such as a channel or pond with puddle clay (puddle, puddling) – a watertight (low hydraulic conductivity) material based on clay and water mixed to be workable. Puddle clay as ...

core extending down into the underlying

London Clay The London Clay Formation is a marine geological formation of Ypresian (early Eocene Epoch, c. 56–49 million years ago) age which crops out in the southeast of England. The London Clay is well known for its fossil content. The fossils from t ...

and gravel/earth shoulders at a slope of 1 in 3. The top of the embankment is 12 m above the surrounding land. The key engineering parameters are: The reservoir has a 1 km central gravel/earth embankment breakwater running north-south and designed to reduce wave action.

Operation

Water is abstracted from the River Thames downstream of Penton Hook Weir at up to and flows via the 1.26 km Laleham Aqueduct to a pumping station (51°24'56.0"N 0°28'36.9"W) at the western embankment of the reservoir. The pumping station lifts water into the reservoir. An outlet tower is located adjacent to the north-east embankment (51°25'17.4"N 0°26'57.1"W). Water is discharged into the Staines Reservoirs Aqueduct which runs round the north of the reservoir to the Kempton Park and Hampton water treatment works. The Metropolitan Water Board operated the reservoir until the Board was abolished in 1974 under the provisions of the ''Water Act 1973'' (c. 37) ownership and control transferred to the

Thames Water Authority The Thames Water Authority was one of ten regional water authorities created in the UK on 1 April 1974 under the provisions of the Water Act 1973 to bring together all the water management functions of the region in one public body. Predece ...

. Under the provisions of the

Water Act 1989 The Water Act 1989 (1989 c.15) is an Act of the Parliament of the United Kingdom that reorganised the bodies responsible for all aspects of water within England and Wales. Whereas previous legislation, particularly the Water Act 1973, had focuse ...

(c. 15) the Thames Water Authority was privatised as

Thames Water Thames Water Utilities Ltd, known as Thames Water, is a large private utility company responsible for the public water supply and waste water treatment in most of Greater London, Luton, the Thames Valley, Surrey, Gloucestershire, north Wiltshir ...

. Sand and gravel were formerly dredged from the reservoir, making the bottom uneven and affecting water circulation. In 2008

digitally modelled the bottom to identify high points where aggregates could be removed. Planning approval was given to remove 1.25 million tonnes of aggregate and two-thirds of the breakwater. This increased the reservoir capacity by 1.26 percent. A jetty and aggregate processing facility was constructed on the west side of the reservoir just north of the intake. The emergency drawdown rate (the rate at which the water level in the reservoir can be reduced) was about 0.25 metres/day. Inspections in 2005-07 identified that this was inadequate, and proposed that the drawdown should be 0.75 m/d as defined in the provisions of the ''Reservoirs Act 1975''. This was achieved by installing twin 1.6 m diameter siphon pipes over the embankment. The valves controlling the outflow are 13 m high and have a flow capacity of 13 m³/s. The discharge pipes are 250 m long and discharge into the Laleham Aqueduct, returning water to the Thames. The reservoir and the land to the west are designated Sites of Nature Conservation Importance, covering some 360 ha and noted for their varied bird life. The Queen Mary Sailing Club is a members sailing club on the reservoir. It owns a subsidiary company Queen Mary Sailsports, bringing all training operations "in house".

References

External links