Fulney Lock - River Welland

[magpie patrick]

Boating, although not general boating I admit!

 

Further idle musings from my hospital bed led to me looking up Fulney Lock, the tidal lock (indeed the only lock) on the Welland. I have seen this lock once, about 30 years ago, and recall being surprised that it could only lock up into the tide, if the tide lower than the non-tidal side then there is only a single pair of gates, known, according to the linked document, as the ebb gates. 

 

Fulney Lock technical note

 

what really surprised me in this note is that the flood gates - two pairs making a proper lock - have no paddles! What strange beast of a lock is this?! Of course the level seaward side is not fixed so there are ways to pass, but it does seem a bizzare structure...

 

(should this be in history and heritage)

[Pluto]

Presumably boats would only enter or leave when the tidal water was higher than that inland, and all the gates were opened when a level was made. The inland waters would rise whilst boats entered/left, and the gates were then shut to prevent flooding. The lock at Tarleton was a little like this, with the addition of a pair of half tide gates about 200 yards above the lock. When boats wanted to enter/leave, the half tide gates were closed and all lock gates opened, possibly just before the tide made a level. With all gates open, it was much easier, and significantly quicker, for sailing barges/flats to enter/leave, so more boats could be handled, particularly if they had to wait for a Spring tide to have enough depth to get up to the lock. The River Douglas was much shallower than today as the channel was scoured out and lowered considerably due to the training walls built on the Ribble for Preston Docks circa 1900.

[David Mack]

56 minutes ago, Pluto said:

Presumably boats would only enter or leave when the tidal water was higher than that inland, and all the gates were opened when a level was made.

Not uncommon practice surely. I have been through the Thames Lock at Brentford like this.

[Pluto]

43 minutes ago, David Mack said:

Not uncommon practice surely. I have been through the Thames Lock at Brentford like this.

It can depend upon how many boats were expected to enter or leave on a single tide. Many larger dock systems used half-tide basins, which opened their gates well before high tide, the level of the basin rising with the tide. Empty or lightly-loaded boats could then be got out of the way before fully-loaded boats had the depth of water necessary for them to enter the docks. Tidal locks were, where possible, used purely as an entry/exit without the use of gates, the opening and closing of which restricted the number of boats using the lock per tide. Sometimes half-tide basins were used, and sometimes the level above the lock was allowed to rise and fall with the top of the tide. It would depend upon how the system, as a whole, was arranged, and relied upon the lock keeper knowing his lock and how to get the best out of it in terms of boats passing in and out. How tidal locks are used today for pleasure traffic is not necessarily how they operated in commercial days.

[magpie patrick]

Fulney Lock dates, I think, to the 1960s. It was built as part of a flood relief scheme and prior to this there was no look or sluice at Spalding and the river was tidal. I guess the lock was built due to the right of navigation and the need for a control structure anyway - easier to build a lock than make the case for not building one. 

 

The notes say one can only pass on a rising tide, as a falling tide risks the ebb gates closing in an uncontrolled manner. It also says the inward flood tide gates have no paddles and the outer ones have had the paddles disabled. 

 

This makes getting out relatively easy, tide level open all gates, go. Incoming is more tricky as you can only use the lock on a rising tide, in theory the same principle but in practice the timing will need to me more precise as they presumably won't let the lock overfill and then empty when the tide goes out, whereas on the way out so long as the gates behind you are closed you're good to go.

[magpie patrick]

I've got my head round my issue now.

 

First, clearly this works for the relatively low levels of traffic (best described as a boat every now and then) but..

 

Lock layout below

 

 

heading towards the Wash - left to right. 

 

Tide out, ebb gates closed, go past inner flood gates, close them behind you, wait in the chamber for flood tide to open ebb gates, go (someone will close upper gates behind you and prevent inundation of Spalding) 

 

Heading from the Wash, hang around outside of the ebb gates waiting for the tide to come in - not much chamber as outer flood gates are also here , when the ebb gates are pushed open hoof it before the flood gates have to be closed.

 

You've probably got a window of an hour or more outbound between level and the tide starting to ebb (they don't allow passage in the ebb level) but only a few minutes inbound before the flood gates close and you have to wsit for the next flood level