The Prescott Channel in July 2006, with cultivated fig tree
|Navigation authority||Canal & River Trust|
|Date of act||1930|
|Connects to||Bow Back Rivers|
The Prescott Channel was built in 1930–35 as part of a flood relief scheme for the River Lee Navigation in the East End of London, England, and was named after Sir William Prescott, the then chairman of the Lee Conservancy Board. Rubble from the demolished Euston Arch was used in 1962 to improve the channel, which forms part of the Bow Back Rivers.
Three Mills Lock is a lock in the channel to allow passage of freight for the London 2012 Olympics by a process of canalisation (with the result of stopping the tidal flow) on the channel and the River Lee northwards. It was constructed between March 2007and June 2009. The project was credited with offering additional benefits:-
"As well as helping barges carrying construction materials and recyclables between Stratford and the River Thames, the lock will also create new opportunities for leisure boats, water taxis, trip boats and floating restaurants."
A major benefit for British Waterways was the increased value of the land which it holds in areas no longer subject to flooding,which it was expected would exceed the cost of the project.
The lock is 62 metres long, 8 metres wide and 2.4 metres deep, and can hold two 350 tonne barges (other locks on the Lower Lee limited barges to about 120 tonnes).It was designed by Tony Gee and Partners and built by Volker Stevin.
On 2 June 2008, work on the channel brought up a 2,200-pound (1 t) Hermann Second World War time bomb. Residents were evacuated, tube and rail services were disrupted, and flights from London City Airport were curtailed during the emergency. The 67-year-old, booby-trapped bomb was finally made safe, after five days, in a controlled explosion that threw 400 tonnes of sand into the air. Major Matt Davies, of the Army Bomb disposal unit said "If it had gone off in wartime there would have been large fragments up to a mile away which could have destroyed buildings and sewers". He added "This is the biggest unexploded bomb we have found in central London."
In 2009, again as part of the project to build the lock, 29 stones from the Euston Arch were raised from the river bed and presented to the Euston Arch Trust. One stone had already been salvaged in 1994 by Dan Cruickshank, as part of a BBC Television programme called 'One Foot in the Past'.
Three Mills Lock was delivered ten months behind the planned schedule, which severely limited its usefulness to the builders of the various Olympic Park venues. A further planned use was for the delivery of materials for the Crossrail project.However the lock has in fact rarely been used by freight barges.
In August 2013, a long period of hot dry weather followed by heavy rain washed polluted road run-off water into the Lower Lea, causing deoxygenation of the water. The role of the canalisation of the Bow Back Rivers in and around the Olympic Park, with its consequences for tidal flow have been implicated in the considerable levels of fish kill which resulted from the incident.
The River Parrett flows through the counties of Dorset and Somerset in South West England, from its source in the Thorney Mills springs in the hills around Chedington in Dorset. Flowing northwest through Somerset and the Somerset Levels to its mouth at Burnham-on-Sea, into the Bridgwater Bay nature reserve on the Bristol Channel, the Parrett and its tributaries drain an area of 660 square miles (1,700 km2) – about 50 per cent of Somerset's land area, with a population of 300,000.
The River Witham is a river almost entirely in the county of Lincolnshire in the east of England. It rises south of Grantham close to South Witham at, passes through the centre of Grantham, passes Lincoln at and at Boston, , flows into The Haven, a tidal arm of The Wash, near RSPB Frampton Marsh. The name "Witham" seems to be extremely old and of unknown origin. Archaeological and documentary evidence shows the importance of the Witham as a navigable river from the Iron Age onwards. From Roman times it was navigable to Lincoln, from where the Fossdyke was constructed to link it to the River Trent. The mouth of the river moved in 1014 following severe flooding, and Boston became important as a port.
The River Weaver is a river, navigable in its lower reaches, running in a curving route anti-clockwise across west Cheshire, northern England. Improvements to the river to make it navigable were authorised in 1720 and the work, which included eleven locks, was completed in 1732. An unusual clause in the enabling Act of Parliament stipulated that profits should be given to the County of Cheshire for the improvement of roads and bridges, but the navigation was not initially profitable, and it was 1775 before the first payments were made. Trade continued to rise, and by 1845, over £500,000 had been given to the county.
The River Lea is a river in South East England. It originates in the Chiltern Hills, England, and flows southeast through east London where it meets the River Thames, the last looping section being known as Bow Creek. It is one of the largest rivers in London and the easternmost major tributary of the Thames. Its valley creates a long chain of marshy ground along its lower length, much of which has been used for gravel and mineral extraction, reservoirs and industry. Much of the river has been canalised to provide a navigable route for boats into eastern Hertfordshire, known as the Lee Navigation. While the lower Lea remains somewhat polluted, its upper stretch and tributaries, classified as chalk streams, are a major source of drinking water for London. A diversion known as the New River, opened in 1613, abstracts clean water away from the lower stretch of the river for drinking. Its origins in the Chilterns contribute to the extreme hardness of London tap water.
The Hertford Union Canal or Duckett's Cut is just over 1 mile (1.6 km) long in the London Borough of Tower Hamlets in East London. It connects the Regent's Canal to the Lee Navigation. It was opened in 1830 but quickly proved to be a commercial failure. It was acquired by the Regents Canal Company in 1857, and became part of the Grand Union Canal in 1927.
The Lee Navigation is a canalised river incorporating the River Lea. It flows from Hertford Castle Weir to the River Thames at Bow Creek; its first lock is Hertford Lock and its last Bow Locks.
Bow Creek is a 2.25-mile (3.6 km) long tidal estuary of the English River Lea and is part of the Bow Back Rivers. Below Bow Locks the creek forms the boundary between the London Boroughs of Newham and Tower Hamlets, in East London.
Bow Back Rivers or Stratford Back Rivers is a complex of waterways between Bow and Stratford in east London, England, which connect the River Lea to the River Thames. Starting in the twelfth century, works were carried out to drain Stratford Marshes and several of the waterways were constructed to power watermills. Bow Creek provided the final outfall to the Thames, and the other channels were called Abbey Creek, Channelsea River, City Mill River, Prescott Channel, Pudding Mill River, Saint Thomas Creek, Three Mills Back River, Three Mills Wall River and Waterworks River.
City Mill River is part of the Bow Back Rivers in London, England. It formerly fed City Mill, used for the production of chemicals in the late nineteenth and early twentieth centuries. In the 1930s, the mill was removed and the river was isolated from the tides by the construction of locks at both ends. City Mill Lock, at the southern end, has been refurbished and reopened in 2010.
The Tees Barrage is a barrage across the River Tees just upriver of Blue House Point in the borough of Stockton-on-Tees in North East of England and is used to control the flow of the river, preventing flooding and the effects of tidal change. The Tees Barrage comprises a river barrage, road bridge, footbridge, barge lock, fish pass and white water course. The waters above the barrage are permanently held at the level of an average high tide and are used for watersports such as canoeing, jet skiing, dragonboat racing and incorporates a 1 km rowing course. The barrage is accessible by road only from Thornaby-on-Tees as there is very limited road access to the north bank of the Tees.
Hertford Castle Weir is a weir located in Hertford near to Hertford Castle and next to Hertford Theatre.
Bow Locks (No20) is a set of bi-directional locks in Bromley-by-Bow in the London Borough of Tower Hamlets and Newham. The locks link the tidal Bow Creek to the River Lee Navigation, which is a canalised river. These locks were first built in 1850 and then rebuilt in 1930, at the same time as the Prescott Channel was cut nearby. At high tide, the tide from Bow Creek formerly flowed through Bow Locks, to raise the level of the canals, such as the Limehouse Cut. In 2000, these locks were modified to keep the tide out, to reduce silting in the canal system.
The Middle Level Navigations are a network of waterways in England, primarily used for land drainage, which lie in The Fens between the Rivers Nene and Great Ouse, and between the cities of Peterborough and Cambridge. Most of the area through which they run is at or below sea level, and attempts to protect it from inundation have been carried out since 1480. The Middle Level was given its name by the Dutch Engineer Cornelius Vermuyden in 1642, who subsequently constructed several drainage channels to make the area suitable for agriculture. Water levels were always managed to allow navigation, and Commissioners were established in 1754 to maintain the waterways and collect tolls from commercial traffic.
The Lea Valley Walk is a 50-mile (80 km) long-distance path located between Leagrave, the source of the River Lea near Luton, and the Thames, at Limehouse Basin, Limehouse, east London. From its source much of the walk is rural. At Hertford the path follows the towpath of the River Lee Navigation, and it becomes increasingly urbanised as it approaches London. The walk was opened in 1993 and is waymarked throughout using a swan logo.
The Lee Flood Relief Channel (FRC) is located in the Lea Valley and flows between Ware, Hertfordshire, and Stratford, east London. Work started on the channel in 1947 following major flooding and it was fully operational by 1976. The channel incorporates existing watercourses, lakes, and new channels. Water from the channel feeds the Lee Valley Reservoir Chain.
Channelsea River is a tidal river in London, England, one of the Bow Back Rivers that flow into the Bow Creek part of the River Lea, which in turn flows into the River Thames.
Three Mills Lock, also known as the Prescott Lock is a lock on the Prescott Channel on the River Lea in London. The project was led by British Waterways and the lock officially opened on 5 June 2009.
Three Mills Wall River Weir is a weir on the Bow Back Rivers, in Mill Meads in the London Borough of Newham, England, near to Three Mills. It was built in 2009, when the Bow Back Rivers were refurbished to make them a key feature of the Queen Elizabeth Olympic Park, and maintains water levels through much of the park in conjunction with the Three Mills Lock and sluice on the Prescott Channel.
The Hackney Cut is an artificial channel of the Lee Navigation built in England in 1769 by the River Lea Trustees to straighten and improve the Navigation. It begins at the Middlesex Filter Beds Weir, below Lea Bridge, and is situated in the (modern) London Borough of Hackney. When built it contained two pound locks and a half-lock, but was rebuilt to handle larger barges in the 1850s, and now only Old Ford Lock, which is actually a duplicated pair, remains.
Carpenter's Road Lock is a rising radial lock in the London Borough of Newham, near Marshgate Lane in Stratford, England. It is located on the Bow Back Rivers and was constructed in 1933/34. It is the only lock in Britain with rising radial gates at both ends. British Waterways were hoping to restore it as part of the upgrade to Bow Back Rivers which took place for the 2012 Summer Olympics, but the gantries which enabled the gates to be raised were demolished to accommodate a wide bridge giving access to the main stadium. After the Games, most of the overbridge was removed. Funding for the restoration of the lock was in place by early 2016, and it is expected to be brought back into use in 2017.