timeline item
Here is the information we have
on the item you selected
More like this
© 2020 Engineering Timelines
engineering timelines
explore ... how   explore ... why   explore ... where   explore ... who  
home  •  NEWS  •  search  •  FAQs  •  references  •  about  •  sponsors + links
Island Barn Reservoir
East Molesey, Surrey, UK
associated engineer
William Booth Bryan
date  24th October 1908 - 4th November 1911
UK era  Modern  |  category  Dam/Reservoir  |  reference  TQ137671
ICE reference number  HEW 2232
Island Barn storage reservoir built on the site of a former barn belonging to Island Farm, on land encircled by the Mole and Ember rivers, south west of Kingston Upon Thames and Hampton Court in Surrey (inside the M25). It was used a training location for amphibious vehicles during World War II, and remains in use as part of London's water supply system.
To satisfy growing demand for water supply storage, the Lambeth Waterworks Company obtained an Act of Parliament — the Lambeth Waterworks Act 1900 — to construct a non-impounding reservoir. The company acquired the necessary land and their engineer Thomas F. Parkes designed a reservoir that would hold some 4,550 million litres of water.
London’s eight water companies were taken over by the Metropolitan Water Board in 1904. Under the Metropolitan Water Board (Various Powers) Act 1907, the board sought extra time in which to construct the reservoir permitted by the earlier Act. An extension of seven years was granted, but considerable opposition by local authorities forced modifications to the design and a reduction of the proposed surface area. The amended design was prepared by the board’s chief engineer William Booth Bryan (1848-1914).
Charles E. Hearson, Chairman of the Works & Stores Committee of the Metropolitan Water Board, began the construction by cutting the first sod on 24th October 1908 accompanied by John Burns MP (1858-1943), President of the Local Government Board.
The reservoir's embankment dam is 2.74km long and contains 1.27 million tonnes of soil excavated from inside the reservoir footprint. The dam has a core of puddled clay that extends down through a thick bed of gravel to the underlying London clay. The trenches dug for the core repeatedly filled with water during construction (rivers surround the site) and the contractor worked in several places at once &msdash; employing up to 1,200 labourers in the process.
The exterior slopes are grassed, while the interior faces are lined with concrete slabs from 3.15m to 1.22m below top water level and with 90,000 precast concrete blocks above. The top of the lining has an in situ concrete coping. The earthworks for the embankment comprise some 72,600 cu m of earth and about 85,600 cu m of puddle clay. The scheme also contains 3,960 tonnes of cement, 2,475 tonnes of cast iron pipes and 577 tonnes of steel pipes.
Water to fill the reservoir comes from the River Thames, initially from the intake works at West Molesey (TQ114687), which supplies Walton Pumping Station (TQ117683) through a 439m long open channel 6.7m wide with a water depth of 2.44m. Then water is pumped through mains 910mm and 1.4m in diameter — some of the larger mains were purpose-built and are about 2.7km long — between Walton and Island Barn. If required, additional water can flow under gravity to Island Barn from the Knight and Bessborough reservoirs.
Supply pipes are brought into a chamber with granite balustrades at the inlet works (TQ137674) at the west end of the north bank, where the water discharges over a long granite weir and down steps into the reservoir. Two outlet towers (TQ142672) with regulating valves lie on the north east shore. After storage, water flows through the mains to the treatment works at Surbiton (TQ173672).
The reservoir contains 4,190 million litres and has a water area of around 49 hectares. The contract price was £152,727 and it was opened on 4th November 1911 by Sir Thomas Vezey Strong (1857-1920), then Lord Mayor of London and Privy Counsellor.
During World War II (1939-45) Island Barn Reservoir and its surroundings were used as a training ground for amphibious vehicles. Island Barn Reservoir Sailing Club (established 1959) has held dinghy racing and sailing events on the reservoir since 1973 and has a clubhouse on the west side of the inlet works.
Between 1992 and 1998 some 1.3 million tonnes of gravel aggregate was extracted from the reservoir bed.
Contractor: Robert McAlpine & Sons
Research: ECPK
"Island Barn Reservoir: Ceremony of Cutting the First Sod October 24, 1908", Metropolitan Water Board, London, 1908
"Island Barn Reservoir: Opening Ceremony by the Right Hon. Sir T. Vezey Strong, the Lord Mayor of London, Saturday, 4th November 1911", Metropolitan Water Board, London, 1911
"Surrey Minerals Plan: Assessment of Potential Yield for Selected Primary Aggregate Sites, Surrey" by GWP Consultants, Charlbury, September 2009
reference sources   CEH Lond

Island Barn Reservoir