River depths survey !

boatone

boatone

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Just a few cables from Boulters Lock
www.tmba.org.uk
Well, according to the new charter, the EA now define the fairway as the middle third of the river and that is where, by implication, they endeavour to keep the published navigable depths.

So, how about we try to compile a database of places where we have grounded (touched bottom) when actually 'in the fairway' ?

A few places I can mention for starters where I have grimaced in recent years:
1. Above and below Clifton Hampden bridge - seems to be hard rock! There is a starb'd hand buoy about quarter mile or so below bridge but still hit bottom when keeping well away from it.
2. Abingdon - mid river by the Boating Centre below the bridge there is a significant shoal and the main channel is towards the right bank traveling upstream.
3. Abingdon - a little further downstream where the river runs alongside the road - starb'd hand buoy. Got safely past it going upriver last summer, relaxed .... and then hit the bottom!
4. Benson Lock upper lock cut where it joins the river
5. Reading below Caversham - opposite Better Boating. Isolated incident a couple of summers ago - definitely hit something in middle of main channel.

Add to the list if you can - need accurate location, date and approximate draft.
 
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All very well to define the middle third as the bit where its deep enough but on narrow bits in busy areas having 2/3 of the river of uncertain depth might make for throlling boating. Just musing, if I, in a boat 3.2m wide, want to pass you, in a similarly sized vessel, using a reasonable passing distance in open waters of at least a boat's width then, rounding up, we need the river to be 30m wide to get that 10m of fairway. Now let's move that scenario to two barges meeting, at 4.5m wide each. All fine on Walton Reach but could be more troublesome where there is less water.

Am I being too generous in my passing distances? If I meet someone coming the other way in, say, the Desborough Cut it seems reasonable to me to pull as far over as is sensible to maximise the distance between us. If it was the cut to Romney Lock or above Old Windsor that would be fair grounds for dead slow and creeping cautiously.

How does that "middle third" work on a bend, do they dredge to get a precise middle? I have a mental picture of a shore based bureaucrat with a map, dividers and a pencil line:-)
 
I touched the bottom coming out of Days Lock last week on the downstream side, had a few extra peeps in the back which maybe maybe lowered the outdrives a few inches, throughly mangled one set of props, the weir appears to have created a sandbank right across the entrance:mad:
 
What they say is:
We will maintain a fairway, normally at least the middle third of the river, between each lock.......We will mark underwater obstructions that we are aware of in the fairway.........We will mark the navigation channel with signs to identify the channel and danger areas.

Without being too pedantic, it seems to me that the major concern is that river depths are decreasing and there is only very limited dredging.

Now, in most stretches of the river my experience is that the actual depth of water is considerably greater than the EA's commitment to maintain, but there are a few places such as those I have mentioned, where the depths are definitely right on the limit or possibly worse and we do need to be careful.

So, my intent here is to invite everyone to assist in building a list of hazardous areas 'in the fairway' and then to investigate with the EA what, if anything can be done to improve the depth or at least make sure that better channel marking is available. At the moment I think the bit above about marking the channel basically means the notices stuck on trees at various places pointing the way !
 
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I can concur with each of your above mentioned areas with the possible exception of Caversham, where I know I was way off track when I did hit the bottom.

I have some concern about not being able to make it above Days Lock in the next two weeks as a result.
 
How does that "middle third" work on a bend, do they dredge to get a precise middle? I have a mental picture of a shore based bureaucrat with a map, dividers and a pencil line

Concerning bends it is normally deepest on the outside,where the current flows fastest and will drop less sentiment during summer low flows and less by way of boulders during winter floods.
 
Brayman said:
What is is this word "Dredging" ?????
Click to expand...

Just in case the hotel degree managers at EA, have never heard of it....

dredging.gif
 
At the risk of repeating myself, they have sold me a registration for my boat for the WHOLE river not just a bit of it, so now they need to deliver or leave it to another organisation that can.

Are we all going to start anchoring out overnight in the central third of the river cos we cannot moor up anywhere to the bank?
Travelling along at night could get a bit difficult with boats anchored up everywhere.
The whole thing is a farce!

They have to dredge the main popular moorings as well. By all means charge the landowner or whatever, just dredge the flippin moorings.

(Back to sleep now. Two more days till I leave my job after 12 years....yippee!!)
 
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They have to dredge the main popular moorings as well. By all means charge the landowner or whatever, just dredge the flippin moorings
>>>

A very fair point. Having said that, if I were a riparian owner I'd grumble if I was billed for unexpected dredging, and if I were charging a fiver (or whatever) a pop, doubly so if I let out longer term moornings, I'd expect I would have to front something to keep the depth suitable. But EA moorings should perhaps be dregded to match the fairway out as far as the fairway. When they are only 2'6" deep is there any wonder they fill up with "cruising" narrowboats? Relatively few cruisers can use them.
 
This is not a direct answer to the initial proposition of mapping the shallows, but may be of interest.

I believe that one of the problems that the EA face with dredging is that the dredged material is classified as "hazourdous waste", and they have very few places to dump it. I'm sure it could be towed out to sea for a reasonable cost, however neighbours and I have received a planning "consultation" (wording worthy of one of Sir Humphrey's schemes for getting his own way in "Yes Minister", but let's not go into that) for "cleaning and removing" existing dreged materials from Penton Lake to make way for dumping new dredged materials, the implication presumably being that they want to do a spot of dredging over the next few years

R
 
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