Bi-directional gates and locks Lock (water navigation)

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bi-directional gates @ 1 chamber end of tidal lock (located in veurne on canal nieuwpoort - duinkerke)


where lock tidal (i.e. 1 side of lock has water level varies tide) or canal meets river level may vary, water on tidal or river side (the downstream side) may rise above water on normal upper side. upstream pointing doors fail job, , drift open. prevent water flowing wrong way through lock, there need @ least 1 set of gates pointing in wrong direction. if desirable boats can use lock in these circumstances, there needs full set of gates pointing towards tidal or river side. usual method have gates pointing in opposite directions @ both ends of chamber (alternatively, paired stop lock arrangement of 2 separate sequential locks pointing in opposite directions work here – require chamber). if navigation not required (or impossible) @ 1 extreme (e.g. allow navigation above mid-tide, prevent canal emptying @ low tide) necessary have 1 set of bi-directional gates.



two types of bidirectional locks @ end of marne-rhine canal in independent port of strasbourg


a sea lock 1 connects canal or river directly estuary or ocean. sea locks tidal.







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