The Jubilee River is a hydraulic

channel Channel, channels, channeling, etc., may refer to: Geography * Channel (geography), in physical geography, a landform consisting of the outline (banks) of the path of a narrow body of water. Australia * Channel Country, region of outback Austral ...

in southern England. It is long and is on average wide. It was constructed in the late 1990s and early 2000s to take overflow from the

River Thames The River Thames ( ), known alternatively in parts as the The Isis, River Isis, is a river that flows through southern England including London. At , it is the longest river entirely in England and the Longest rivers of the United Kingdom, se ...

and so alleviate

flood A flood is an overflow of water ( or rarely other fluids) that submerges land that is usually dry. In the sense of "flowing water", the word may also be applied to the inflow of the tide. Floods are an area of study of the discipline hydrol ...

ing to areas in and around the towns of

Maidenhead Maidenhead is a market town in the Royal Borough of Windsor and Maidenhead in the county of Berkshire, England, on the southwestern bank of the River Thames. It had an estimated population of 70,374 and forms part of the border with southern Bu ...

, Windsor, and

Eton Eton most commonly refers to Eton College, a public school in Eton, Berkshire, England. Eton may also refer to: Places *Eton, Berkshire, a town in Berkshire, England * Eton, Georgia, a town in the United States * Éton, a commune in the Meuse dep ...

in the counties of

Berkshire Berkshire ( ; in the 17th century sometimes spelt phonetically as Barkeshire; abbreviated Berks.) is a historic county in South East England. One of the home counties, Berkshire was recognised by Queen Elizabeth II as the Royal County of Berk ...

and

Buckinghamshire Buckinghamshire (), abbreviated Bucks, is a ceremonial county in South East England that borders Greater London to the south-east, Berkshire to the south, Oxfordshire to the west, Northamptonshire to the north, Bedfordshire to the north-ea ...

. It achieves this by taking water from the left (at this point eastern) bank of the Thames upstream of

Boulter's Lock Boulter's Lock is a lock and weir on the River Thames in England north-east of Maidenhead town centre, Berkshire. The present 1912-built lock replaces those at this point of the river to the immediate east dating from the late 16th century an ...

near Maidenhead and returning it via the north bank downstream of Eton. Although successful in its stated aims, residents of villages downstream, such as Wraysbury, claim it has increased flooding in those locations.

Construction

Parts of the towns of Windsor, Eton and Maidenhead are prone to flooding, because they are built on the flood plain of the River Thames. The concept of a parallel channel which could take water from the Thames above Maidenhead and return it below Windsor was conceived in the 1980s, and became known as the Maidenhead, Windsor and Eton Flood Alleviation Scheme. When the ten regional water authorities were privatised, as a result 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 ...

, responsibility for rivers passed to the

National Rivers Authority The National Rivers Authority (NRA) was one of the forerunners of the Environment Agency of England and Wales, existing between 1989 and 1996. Before 1989 the regulation of the aquatic environment had largely been carried out by the ten region ...

, which soon afterwards submitted plans for a channel which would be wide and long. In October 1992 a planning enquiry was held to consider the proposals. During that enquiry, P. Ackers, one of the assessors, expressed grave doubts about the hydraulic modelling that had been used to justify the scheme, suggesting that it was too optimistic. The scheme did not receive government approval until 1995; around the same time, there was further reorganisation of the water industry, with the

Environment Agency The Environment Agency (EA) is a non-departmental public body, established in 1996 and sponsored by the United Kingdom government's Department for Environment, Food and Rural Affairs, with responsibilities relating to the protection and enha ...

replacing the National Rivers Authority. Although Mr Ackers' concerns had not been addressed, it commissioned the design and construction of the scheme as originally conceived, at a cost of £110 million. Throughout the planning process, from initial feasibility studies to delivery of the project, Lewin, Fryer and Partners were the consulting engineers. Principal works were the creation of the channel, various flow control mechanisms and bridges for road, rail and foot traffic. One of the challenges was the Dorney Bridge, built to take the channel beneath the

Great Western Main Line The Great Western Main Line (GWML) is a main line railway in England that runs westwards from London Paddington to . It connects to other main lines such as those from Reading to Penzance and Swindon to Swansea. Opened in 1841, it was the or ...

. The 19th-century

Brunel Isambard Kingdom Brunel (; 9 April 1806 – 15 September 1859) was a British civil engineer who is considered "one of the most ingenious and prolific figures in engineering history," "one of the 19th-century engineering giants," and "one ...

-designed railway embankment continued in use, carrying passenger and goods trains between London and destinations including

South Wales South Wales ( cy, De Cymru) is a loosely defined region of Wales bordered by England to the east and mid Wales to the north. Generally considered to include the historic counties of Glamorgan and Monmouthshire, south Wales extends westwards ...

, Cornwall and Bristol throughout construction. The high embankment was stabilised along 30m of its length by freezing over a period of three months, using 175 brine tubes cooled to . A tunnel was excavated through the frozen ground to just wider than the two long preformed concrete box sections, which were jacked through as the excavation proceeded. This created a wide by high concrete

culvert A culvert is a structure that channels water past an obstacle or to a subterranean waterway. Typically embedded so as to be surrounded by soil, a culvert may be made from a pipe, reinforced concrete or other material. In the United Kingdom ...

which can be seen from the Bath Road Bridge. The channel also had to be taken through

Black Potts Viaduct Black is a color which results from the absence or complete absorption of visible light. It is an achromatic color, without hue, like white and grey. It is often used symbolically or figuratively to represent darkness. Black and white have o ...

, a series of 13 brick arches carrying the Waterloo to Windsor railway line over the Thames flood plain. Protective concrete and blue brick barriers were built around the older brickwork to preserve the viaduct's structural integrity, as well as to control gates to adjust the amount of water rejoining the Thames immediately downstream. The channel involved complex civil engineering to deal with utility conduits, roads and railways, as well as ecological and social issues, entailing compulsory purchases, community lectures and consultations and a public enquiry. For example at Manor Farm a weir was constructed. Conception to fruition took about 20 years. Water is admitted to the river through sluice gates at the upstream end of the channel near Taplow. This is normally controlled by measurements of the water levels below

Boulters Lock Boulter's Lock is a lock and weir on the River Thames in England north-east of Maidenhead town centre, Berkshire. The present 1912-built lock replaces those at this point of the river to the immediate east dating from the late 16th century and ...

and the estimated flow of the Thames at the Datchet gauging station near Windsor. The first serious test of the new structure occurred during the flooding of early January 2003, and revealed a number of defects in the design. With both the Boulters Lock levels and the Datchet flow indicating that the channel was needed, the Taplow sluices were opened briefly on 1 January, but were then shut again until 4 January, by which time the Boulters Lock levels were above the target levels, and the flow at Datchet was some 320 cubic metres per second, 140 cubic metres per second above the recommended flow. A subsequent investigation revealed that the Environment Agency had known there were defects in the channel since November 2002, and this had been a major factor in not operating it correctly. When flood water was admitted to the channel, the flows were well short of its designed maximum flow capacity, and yet there was significant erosion of the banks in several places. There was considerable erosion at the Taplow Sluice, due to the lack of a

stilling basin A spillway is a structure used to provide the controlled release of water downstream from a dam or levee, typically into the riverbed of the dammed river itself. In the United Kingdom, they may be known as overflow channels. Spillways ensure tha ...

; embankments at Marsh Lane were badly damaged; the weir at Manor Farm was bent in the middle; the protection on the downstream face of Slough weir was swept away; and in Datchet, the Myrke embankment nearly collapsed. An independent assessment by the engineering consultancy WS Atkins identified that the actual capacity of the channel was around two-thirds of its design capacity, and factors affecting this were the banks being too low, the use of inappropriate materials, and failure to follow standard design criteria. A programme of repairs and upgrades to rectify the problems began, at a cost of £3.5 million, and took until 2006 to complete. The Environment Agency sued their lead design consultants for recovery of the remedial costs, and were refunded £2.75 million in an out-of-court settlement, after they admitted that the design and construction were sub-standard.

Name

The name used during planning was the "Maidenhead, Windsor and Eton Flood Alleviation Scheme" (MWEFAS). The choice of a name for the river was put to the local population in a poll. The result was a strong preference for 'Jubilee', as it was being completed in Queen Elizabeth's Golden Jubilee year of 2002 and one of the Queen's main residences is at Windsor Castle, in one of the three towns being protected by the scheme.

In use

The watercourse was designed to look like a natural river; its banks have artificially constructed wildlife habitats intended to replace those lost from the banks of the Thames during urban expansion in the 19th and 20th centuries. During construction of reed beds and of wet woodland were laid down and about 250,000 trees were planted. The river is well used by walkers, runners, swimmers, canoeists, wildlife enthusiasts and cyclists: a footpath combined with National Cycle Route 61 runs along virtually its entire length. A wide variety of bird life can be seen along the river, including green woodpeckers, cormorants, lapwing and red kites. During flooding in the early months of 2014, some residents of

Ham Island Ham Island is an inhabited man-made island of roughly 50 hectares (125 acres) in the River Thames in Old Windsor in England. It was a mature meander of the Thames until a channel was dug, the New Cut, to build Old Windsor Lock which reduced th ...

(in Old Windsor) and Wraysbury said that the Jubilee River had increased the height of the flooded Thames in those villages which, along with much of the river upstream of London, saw water levels unprecedented since 1947. Wraysbury had also suffered significant flooding in 2003. The

in the 2010s is undertaking a widening and dredging programme of Thames works to assist with downstream flows.

References

Bibliography

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External links