Editing Richmond Lock and Footbridge (section)

===Details of design===
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A barge lock was constructed against the north-east ("[[Surrey]]") side. This is followed by four immense brick [[pier (architecture)|piers]] protected by large [[ashlar]] stone [[cutwater]]s (starlings). These in turn support relatively thin stone [[Ashlar|dressings]] reaching to the metal parapet level, carved in a classical style with [[reredo]]s and [[cornice]]s, supporting painted metal arches. A matching-colour [[balustrade]] is above the arches finished with black lanterns, metal pillars and simple [[finial]]s. The piers house the barriers and the arches support a pair of horizontal [[deck (bridge)|decks]] (walkways). Against the opposite bank is a gently elevated slipway accessed from upstream and downstream parts of the river. As a superstructure was required to hold the suspended barriers, authorities agreed to build this in the form of two footbridges.<ref>{{cite web | url = http://www.touruk.co.uk/london_bridges/richmond_lock1.htm | title = Richmond Lock | work = London Bridges|publisher = Just Tour Limited | access-date = 30 April 2020 | url-status = dead | archive-url = https://web.archive.org/web/20070927065954/http://www.touruk.co.uk/london_bridges/richmond_lock1.htm | archive-date = 27 September 2007 | df = dmy-all }}</ref><ref>{{cite web | url = http://www.pbase.com/john_cooper/richmond_footbridge | title = Richmond Footbridge | author=  Cooper, John | website = PBase.com|access-date = 30 April 2020}}</ref>
The bridge was formally opened on 19 May 1894 by the then Duke of York (who later became King [[George V of the United Kingdom|George V]]), having cost £61,000 ({{Inflation|UK|61,000|1892|r=-5|fmt=eq|cursign=£}}).<ref name=listing/>

Richmond Lock is a half-tide lock and (half-tide) barrage which incorporates a public footbridge. The footbridge crosses the conventional lock, the barrages and the slipway, which comprises three vertical steel sluice gates suspended from the footbridge structure. Each sluice gate weighs 32 tons, is {{convert|66|ft}} in width and {{convert|12|ft}} in depth. The lock permits passage of vessels up to {{convert|250|feet}} long by 26 feet 8&nbsp;inches [[Beam (nautical)|wide]].

For about two hours each side of the published time of [[high tide]] the three sluice gates are raised into the footbridge supports above, and river traffic can pass through the barrage unimpeded. For the rest of the tidal cycle sluice gates are lowered – ships and boats must use the lock alongside the barrage at a cost of {{as of|2022|alt=£10 per boat}}. Rowing boats and kayaks can use the roller solid slipways which reach an apex above the height of the barrages. The maximum fall of the lock is {{convert|10|ft}}.