Middle Level Navigations
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The Middle Level Navigations are a network of waterways in England, primarily used for land drainage, between the Rivers Nene and Great Ouse, between Peterborough and Cambridge.
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[edit] History
The Middle Levels of the Fens are a low-lying area of approximately 700 square kilometres, much of which is at or below sea level. Attempts to protect them from inundation, and to make them suitable for agriculture began in 1490, when the Bishop of Ely, John Morton, constructed a 12 mile (19 km) straight cut from Stanground to Guyhirne. The next significant advance was in 1630, when the Dutch Engineer Cornelius Vermuyden was employed by the Earl of Bedford and others to drain the Fens. The Old Bedford River was cut from Earith to Salters Lode, a distance of 21 miles (34 km), and provided sufficient drainage that the land could be used for summer grazing. In 1650, he supervised the construction of the New Bedford River, running parallel to the Old, and the Middle Levels area was protected. The Forty Foot, Twenty Foot and Sixteen Foot Rivers were cut soon afterwards, to drain water from the area to Salters Lode and Welches Dam.[1]
As the land dried, the peaty soils shrank, causing the land surface to drop, and so the Middle Level Main Drain was constructed in 1844, in order that water could flow by gravity to St Germans, where the levels of the tidal river were about 7 ft (2.5m) lower than at Salters Lode. In 1862 an Act of Parliament created the Middle Level Commissioners as a separate body to the Bedford Level Corporation, and they embarked on a series of improvements.[1] Drainage was always the primary function, but navigation was also important, and the new body had powers to charge tolls for the use of the waterways.
[edit] Pumping Stations
By the early 1930s, gravity drainage was no longer adequate, as land levels continued to fall, and a pumping station was constructed at St Germans, opening in 1934. It was paid for by a grant, given on condition that three quarters of the workforce were from the local area. The capacity of the station was increased in 1951 and again in 1969/70. From 1977 to 1983, a series of improvements were carried out, which included the construction of a pumping station at Tebbits Bridge on Bevills Leam, and a lock at Lodes End. The banks of the Old River Nene were raised and clay puddling was used to retain the water, and major improvements to the Forty Foot, Twenty Foot and Sixteen Foot rivers were made, to maintain water levels for navigation. All of the bridges on the Sixteen Foot River were demolished and replaced to provide wider channels, and St Germans pumping station was again upgraded. [1] The improvements have restricted navigation in the lower south-western area, but greatly improved flood defences.
In April 1998, the St Germans pumping station ran at maximum capacity for over 50 hours,[2] and this led to the decision to replace it with a brand new installation, with 40% extra capacity. Work started in December 2006, and the pumping station, which includes the second largest pumps in Europe, is expected to be operational by mid-2009, after which the existing station will be demolished. A glass wall will enable visitors to see the pumps.[3] There are more than one hundred smaller pumping stations scattered throughout the system to maintain the water levels and prevent flooding.[1]
[edit] Today
The navigations are managed by the Middle Level Commissioners, who are responsible for about 120 miles (192km) of waterway, of which around 100 miles (160km) are navigable. The Commissioners are also responsible for six locks and a number of pumping stations, and are the fourth largest navigation authority in Great Britain.[4]
The navigations often form a short cut for boaters between the River Nene at Peterborough and the River Great Ouse at Salters Lode Lock. The suggested route passes through Stanground Sluice, along King's Dyke to Ashline Lock, and then along Whittlesey Dike to Flood's Ferry junction. From here the route is along the old course of the River Nene, passing through the twin villages of Outwell and Upwell, where the abandoned Wisbech Canal once formed a route back to the new course of the River Nene. The final stretch to Salters Lode lock is along Well Creek, passing over the top of the Middle Level Main Drain on Mullicourt Aqueduct.[5]
The alternative route via Horseway sluice and the Old Bedford River is problematic, as very low water levels between Horseway sluice and Welches Dam lock normally prevent passage.[5][6] This stands to be improved, however, as part of the Fens Waterways Link project.[7]
Access to other parts of the Levels was improved in 2006, when soldiers from the 53rd Field Squadron of the 39 Engineer Regiment raised the level of a Bailey bridge at Ramsey Hollow. This had previously restricted passage, as it was very low, but has been raised by 3 ft (0.9 m). The Inland Waterways Association raised the funding for the additional materials required, and the reconstruction has opened up a 33 mile (53km) cruising ring on the Levels.[8]
[edit] Boat sizes
When the navigations were built, the boats using them were traditional Fen Lighters, which were 46 by 11 ft (14 x 3.3m), and the locks were sized accordingly. However, there has been a programme of increasing the lock sizes to make the waterways accessible to standard narrow boats. Stanground lock was lengthened to 80 ft (24.4m) first, with Ashline lock following, being reopened on 1 April 1999. Salter's Lode lock is restricted to 62 ft (18.9m), although it is possible for longer boats to pass straight through at certain states of the tide.[5] Welches Dam Lock is still sized for Fen Lighters.
[edit] References
- ^ a b c d St Germans Pumping Station: History
- ^ St Germans Pumping Station: Why?
- ^ St Germans Pumping Station: How?
- ^ Middle Level Commissioners website
- ^ a b c Jim Shead (1999) Middle Level Mysteries, article in Waterways World
- ^ Note on map by Middle Level Commissioners
- ^ Fens Waterways Link Supporting Report 3: Engineering. Environment Agency (2004). Retrieved on 2008-02-06.
- ^ Inland Waterways Association press release 13 Dec 2006