Appley Bridge locks

How long have the two-lock flight at Appley Bridge been out of use? the
Microsoft aerial photo shows them apparently in use, with a dozen boats
in the short pound between them, but last week when we passed (via the
deep lock) they appeared to be almost derelict- rusty paddle gear, and
largish bushes growing out of the lock walls.

JS

Don Aitken wrote:
> On Mon, 07 Jul 2008 13:01:33 +0100, JSprocket <JS@internept.org>
> wrote:
>
>> How long have the two-lock flight at Appley Bridge been out of use? the
>> Microsoft aerial photo shows them apparently in use, with a dozen boats
>> in the short pound between them, but last week when we passed (via the
>> deep lock) they appeared to be almost derelict- rusty paddle gear, and
>> largish bushes growing out of the lock walls.
>>
> I used them in 1996, if that's any help. The 1995 edition of Nicholson
> describes them as "now restored", as does the 1999, and probably all
> sebsequent ones. I don't suppose many people chose to use two locks
> rather than one, and a completly unused lock deteriorates fairly fast,
> besides being an obvious target for those looking to save on
> maintenance. Maybe they'll be restored again, so they can go through
> the same cycle indefinitely.

When we were in the Wigan area they came in and out of use at least
once. We did once overtake a slow and very cautious wide boat that was
going up the single lock by going up the two singles.

On Jul 7, 10:22 pm, David Long <Da...@n0ne.c0m> wrote:
.
>
> My bit of Wigan on GE dates from March/April 2005 - and I think I can
> see cherry blossom near Appley Bridge, so I guess it's from the same
> period.
> --


That is great definition! I can't read boat names on Google Earth.

Tone

On Wed, 9 Jul 2008 19:23:25 +0100, "Pete Stockdale"
<peter.jeanne@****************> wrote:

>
>"JSprocket" <JS@internept.org> wrote in message
>news:g52m4p$p43$1@aioe.org...
>> Pete Stockdale wrote:
>>> I do not follow the argument that two single locks could have replaced
>>> the single to save water.
>>>
>>
>> Look at it this way: going down a 2 metre deep broad lock, say 20x4metres,
>> you use 160 cu m of water. This goes into the pound between the locks, and
>> neglecting leakage the same amount of water is available to fill the
>> second lock (either the level stays up if the lock is full, or you use it
>> to fill the lock if empty). So the total water used is just the 160 cu m.
>>
>> For a single lock 4m deep, you take 20x4x4 = 320 cu m of water down with
>
>> you.
>
>
>.
>
>Trouble is that the way most people operate locks - most of the output of
>the top lock emptying flows to waste down the bottom lock bywash.
>
>The sigle lock consumption is therefor effectively equalled.
>
>With a bit of co-ordinated paddle operation - your theory is of course
>possible, but rarely happens in practice.

In reality, even with sub-optimal operation, it is still better than a
single deep lock.

Firstly, a boat coming uphill will not typically have this problem,
and will only dump 80 cubic metres of water downstream. (because he
will draw from the middle pound before emptying into it).

Secondly, assume that we have a parade of boats going downhill.
Certainly, the first one is going to waste the whole 160 cubic metres,
as the contents of the top lock go over the bywash. However, when he
fills the lower lock, he takes 80 cubic metres out of the middle
pound, and drops it below the weir. The next boat down will empty the
top lock into the middle pound, but it won't go over the weir, it will
just bring the middle pound up to the weir level again.

It also comes down to the fact that in times of water shortage,
working boatmen knew damn well that they had a vested interest in
working the locks so as to avoid running water down without good
reason, and that in times of water shortage it is unlikely that the
bywashes would have been running in any case.