[Tagging] Incorrectly tagging locks on rivers as canals

[Richard Fairhurst]

Volker Schmidt wrote:
> Going back to the original example, I would say, not only the lock but 
> the entire cut, in particular way
> https://www.openstreetmap.org/way/243353333
> should be tagged as waterway=canal. This scheme applies to most river-lock
> arrangements, the "cuts" are nearly almost artificial canals.

Yes.

There's a very big difference from a boating point of view. Taking my home
river as an example, the River Severn, a lock cut such as the one upstream
of Holt Lock makes the approach very easy:
https://www.openstreetmap.org/#map=17/52.26849/-2.26653

Boating on this is exactly like boating on a canal. There is no discernible
current and you can simply hover in midchannel while the lock is prepared
for you (all locks on the Severn are keeper-operated).

Compare this to Gloucester Lock:
https://www.openstreetmap.org/#map=18/51.86538/-2.25197

Here there is no canal approach from upstream - you're straight off the
river into the lock. If you try to hover in midchannel then you will get
swept over Llanthony Weir and River Canal Rescue will have to come and
Tirfor your boat off, which happens two or three times a year to the great
embarrassment of the boat-owner. Consequently you are asked to phone the
lock-keeper in advance so that he can prepare the lock for you and you can
motor straight in. There are lots of warnings about this both off and
online, and rightly so
(https://canalrivertrust.org.uk/refresh/media/thumbnail/27339-new-river-severn-navigation-guide-april-2016.pdf,
https://www.canalworld.net/forums/index.php?/topic/95567-ship-lock-gloucester/&tab=comments#comment-2121288,
http://www.severn-boating.co.uk/sharp.htm etc.).

On some of the larger American river navigations the lock structures are
built right within the main river channel - such as this new $3bn (!) lock
on the Ohio River: https://en.wikipedia.org/wiki/Olmsted_Locks_and_Dam - so
similar caution to Gloucester would apply, particularly in times of high
flow. On a major navigation like that you'd be expected to use VHF to keep
in contact with the lock-keepers, of course.

So there is a very big difference between locks with a canal approach and no
canal approach, and that should be reflected in the tagging.

Richard
(boat-owner, regular contributor and former editor of Waterways World,
former editor of British Waterways' website, founder of Melton Mowbray
Navigation restoration project yadda yadda yadda)




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