Three Mills Lock
{{Short description|Lock on Prescott Channel}}
{{Use dmy dates|date=June 2015}}
{{Use British English|date=June 2015}}
{{Infobox waterlock
| lock_name = Three Mills Lock
| image = Three_Mills_Lock.jpg
| caption = Three Mills Lock
| waterway = River Lee (Bow Back Rivers)
| county = Tower Hamlets
Greater London
| maint =
| operation = Canal & River Trust
| first = 2008–09
| latest =
| length = {{convert|62|m|ft|0}}
| width = {{convert|8|m|ft|1}}
| fall = tidal
| sealevel =
| enda =
| distenda =
| endb =
| distendb =
| map_cue =
| map_image =
| map_text =
| map_width =
| coordinates = {{coord|51.528797|-0.004356|format=dms|region:GB_type:landmark|display=inline,title}}
| extra =
}}
File:Construction site Three Mills Lock.jpg
Three Mills Lock, also known as Prescott Lock, is a lock on the Prescott Channel on the River Lea in London. The current structure was constructed by British Waterways{{cite web|url=http://www.britishwaterways.co.uk/olympics/ |title=Revitalising London’s Olympic Waterways|work=British Waterways)|accessdate=1 August 2008|archive-url=https://web.archive.org/web/20120310012716/http://www.britishwaterways.co.uk/olympics/|archive-date=2012-03-10}} and officially opened on 5 June 2009.
The lock cuts off a section of the Bow Back Rivers from the tide, creating new opportunities for leisure boats, water taxis, trip boats and floating restaurants. It also allowed barges carrying construction materials to access the sites of the London 2012 Olympics and Stratford City.
Original lock
The original Three Mills Lock was constructed in the 1930s{{harvnb |BW-London |2006 |p=3}} as part of a scheme for flood prevention and the creation of employment.{{harvnb |Boyes |Russell |1977 |p=36}} It bypassed the tide mills at Three Mills, and included a sluice structure, which was used to control water levels in the Bow Back Rivers. This structure became inoperative by the mid 1960s, and was removed in the 1980s,{{harvnb |BW-London |2006 |p=36}} by which point the Bow Back Rivers had been classified as "remainder waterways" by the Transport Act 1968, and there was no funding for maintenance.{{cite web |url=http://www.britishwaterways.co.uk/olympics/history |title=Bow Back Rivers - A potted history |publisher=British Waterways |url-status=dead |archive-url=https://web.archive.org/web/20120207004136/http://www.britishwaterways.co.uk/olympics/history/ |archive-date=7 February 2012 |df=dmy-all }} As a consequence of this, the rivers upstream reverted to being tidal. This made navigation difficult, since there was not enough water at low tide, and at high tide, there was insufficient headroom,{{cite web |url=http://www.britishwaterways.co.uk/olympics/three-mills-lock/faqs |title=Restoration Plans |publisher=British Waterways |access-date=2012-02-27|archive-url=https://web.archive.org/web/20120310020610/http://www.britishwaterways.co.uk/olympics/three-mills-lock/faqs|archive-date=2012-03-10}} due to the low level of the Northern Outfall Sewer, which crosses the waterways.
New lock
With the selection of the island formed by the City Mills River and the Lee Navigation as the main site for the 2012 London Olympics, restoration of the Bow Back Rivers was considered an important part of the development,{{harvnb |BW-London |2006 |p=1}} as it would allow construction materials to be delivered by barge.{{harvnb |BW-London |2006 |p=2}}
A new lock and sluice structure was designed for the Prescott Channel, along with the Three Mills Wall River Weir to prevent tidal water flowing backwards through the Three Mills tidal mill.{{harvnb |BW-London |2006 |p=46}} Prior to the development, tidal levels on the Bow Back Rivers reached {{convert|15.8|ft|m}} above ordnance datum (AOD) on spring tides. The sluice is designed to stabilise levels at {{convert|7.5|ft|m}} AOD, so the lock structure has to cope with levels on the downstream side which might be higher or lower than those on the upstream side.{{harvnb |BW-London |2006 |pp=5–6}}
The new lock is {{convert|203|ft|m}} long, {{convert|26|ft|m|0}} wide and {{convert|7.9|ft|m}} deep, and is able to hold two 350-tonne barges (the present locks on the nearby Lee Navigation limit barges to about 120 tonnes).[http://www.glias.org.uk/news/229news.html Notes and News] (April 2007) (Greater London Industrial Archaeology Society) The tidal range is handled by the use of hydraulic sector gates at both ends of the lock, and the structure incorporates two large rising radial gates for flood control in the Bow Back Rivers.
A site in the river just south of this lock is the resting place of the remains of the Euston Arch.{{cite news|title=Euston Arch found at bottom of river|work=The Times|date=4 June 1994}}{{cite web|url=http://www.eustonarch.org/questions.html#12|title=Where are the remains of the arch?|work=Euston Arch Trust|accessdate=16 July 2008|archive-url=https://web.archive.org/web/20100210141417/http://www.eustonarch.org/questions.html#12 |archive-date=10 February 2010}} A footbridge for pedestrians and a fish pass for migrating fish was incorporated into the design of the lock, and British Waterways planned associated improvements to the navigation and tow path, as a part of the Olympic legacy.
An unexploded {{convert|2200|lb|kg|0|adj=on}} Hermann bomb from World War II was found on 2 June 2008. The bomb was made safe, in a controlled explosion, after five days of disruption to tube and rail services.{{cite news|url=http://www.eastlondonadvertiser.co.uk/content/towerhamlets/advertiser/news/story.aspx?brand=ELAOnline&category=news&tBrand=northlondon24&tCategory=newsela&itemid=WeED06%20Jun%202008%2022%3A31%3A52%3A950|title="Hermann" the German bomb says farewell with a bang—after 67 years|work=East London Advertiser|date=6 June 2008|accessdate=9 June 2008|archive-url=https://web.archive.org/web/20090408081211/http://www.eastlondonadvertiser.co.uk/content/towerhamlets/advertiser/news/story.aspx?brand=ELAOnline&category=news&tBrand=northlondon24&tCategory=newsela&itemid=WeED06%20Jun%202008%2022%3A31%3A52%3A950|archive-date=2009-04-08}}
Impact
The effect of building the lock, together with the weir at Three Mills, was to lock out the tide just north of the House Mill. This means that this section of the Bow Back Rivers has ceased to be tidal. The lock was constructed so that barges from two large building projects (the London 2012 Olympics and Stratford City) could pass through the lock, taking spoil out and delivering building materials on to the sites, via a new wharf on the Waterworks River.{{cite news|url=https://www.thetimes.com/comment/register/article/canals-set-to-make-inroads-on-routes-clogged-by-lorries-v8x2n2c9lxs|last=Webster|first=Ben|title=Canals set to make inroads on routes clogged by lorries|work=The Times|date=11 May 2005|access-date=1 August 2008}} Barges can pass directly into the northern section of Bow Creek to the River Thames. The head of water created by the lock may be used to fill the mill pound and once more allow operation of the Three Mills tidal mill.
The lock officially opened on Friday 5 June 2009,{{cite news|url=http://news.bbc.co.uk/1/hi/england/london/8084464.stm|title=Waterway revived as Olympic route|date=2009-06-05|work=BBC News}} but the expected use of the lock for the construction of the Olympic Park was reportedly much lower than originally planned.{{cite web|url=http://www.itnsource.com/shotlist/ITN/2010/02/16/T16021019/?v=0&a=1|title=London 2012 Olympic Games: Canal barge plans 'failing'|date=2010-02-16|archive-url=https://web.archive.org/web/20120229204333/http://www.itnsource.com/shotlist/ITN/2010/02/16/T16021019/?v=0&a=1|archive-date=2012-02-29}}
Transport links
West Ham and Bromley-by-Bow are the nearest London Underground stations. The nearest Docklands Light Railway stations are Bow Church and Pudding Mill Lane
See also
Bibliography
{{Refbegin}}
- {{Cite book
| first1 = John |last1=Boyes |first2=Ronald |last2=Russell
| title = The Canals of Eastern England
| year = 1977
| publisher = David and Charles
| isbn = 978-0-7153-7415-3
}}
- {{cite web
|url = http://www.britishwaterways.co.uk/media/documents/Prescott_Channel_Water_Control_Structure_Project_Explanatory_Statement.pdf
|last = BW-London
|title = Prescott Channel Water Control Structure
|publisher = British Waterways
|date = August 2006
|url-status = dead
|archive-url = https://web.archive.org/web/20120219175153/http://www.britishwaterways.co.uk/media/documents/Prescott_Channel_Water_Control_Structure_Project_Explanatory_Statement.pdf
|archive-date = 19 February 2012
|df = dmy-all
}}
{{refend}}