Netham Lock () is the point at
Netham in
Bristol
Bristol () is a city, ceremonial county and unitary authority in England. Situated on the River Avon, it is bordered by the ceremonial counties of Gloucestershire to the north and Somerset to the south. Bristol is the most populous city in ...
at which boats from the
River Avon, acting as part of the
Kennet and Avon Canal, gain access to Bristol's
Floating Harbour
Bristol Harbour is the harbour in the city of Bristol, England. The harbour covers an area of . It is the former natural tidal river Avon through the city but was made into its current form in 1809 when the tide was prevented from going out perm ...
.
Construction started in 1804 to build the tidal
New Cut and divert the
River Avon along the
Feeder Canal to the harbour; a system designed and built by
William Jessop
William Jessop (23 January 1745 – 18 November 1814) was an English civil engineer, best known for his work on canals, harbours and early railways in the late 18th and early 19th centuries.
Early life
Jessop was born in Devonport, Devon, the ...
and later improved by
Isambard Kingdom 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 "on ...
.
A
weir
A weir or low head dam is a barrier across the width of a river that alters the flow characteristics of water and usually results in a change in the height of the river level. Weirs are also used to control the flow of water for outlets of l ...
carries the river into the New Cut and boats use the adjacent
lock
Lock(s) may refer to:
Common meanings
*Lock and key, a mechanical device used to secure items of importance
*Lock (water navigation), a device for boats to transit between different levels of water, as in a canal
Arts and entertainment
* ''Lock ...
. High
tide
Tides are the rise and fall of sea levels caused by the combined effects of the gravitational forces exerted by the Moon (and to a much lesser extent, the Sun) and are also caused by the Earth and Moon orbiting one another.
Tide tables ...
s often pass over the weir, and the river is effectively tidal to the
next lock upstream at Hanham. Some
spring tide
Tides are the rise and fall of sea levels caused by the combined effects of the gravitational forces exerted by the Moon (and to a much lesser extent, the Sun) and are also caused by the Earth and Moon orbiting one another.
Tide tables ca ...
s can also pass over the weir at Hanham, making the river tidal as far as
Keynsham Lock
Keynsham Lock is a canal lock situated on the River Avon at Keynsham, England.
The Bristol Avon Navigation, which runs the from the Kennet and Avon Canal at Hanham Lock to the Bristol Channel at Avonmouth, was constructed between 1724 and 1 ...
.
Access to the harbour is only possible during the day when the lock keeper will open the gates unless the water level in the river between Netham and Hanham is above or below the level of the harbour.
The maximum dimensions of a vessel which can pass through Netham Lock are:
*Length:
*Beam:
*Draught:
*Headroom:
The lock-keeper's cottage, built in the early nineteenth century, is a
grade II listed building and has a plaque listing it as Bristol Docks building number 1.
The floral displays around the cottage and on the banking have attracted praise.
Netham Lock and the weir form part of Bristol's flood defence mechanisms and it was announced in December 2008 that they would be upgraded as part of the £11 million City Docks Capital Project.
See also
References
External links
{{authority control
Buildings and structures in Bristol
Transport in Bristol
Bristol Harbourside
River Avon, Bristol