Tidal streams in the Crouch

[stuey_two]

Can anyone point me to sources of tidal streams information for the Crouch?
I remember once being moored mid-stream and mid-tide at Paglesham on the Roach and being surprised by the rate at which clumps of seaweed raced past - is the Crouch like that?

 

[johnalison]

I'm not local to the Crouch, though I have sailed it from time to time. I doubt if there are specific stream diagrams for it, but basically it is just a long straightish canal with fairly steep banks, so, yes, the tide does run strongly. If you use your eyes you would expect this. A look at the chart will show you that there is a lot of water coming down from upstream on the ebb and it has to go somewhere. On one of the first occasions I visited there I won a race in the Corinthian's ancient 12sq m Sharpies because I was the only one who saw that the tide would give me a lee bow. In the current phrase, don't overthink the problem.

 

[TheEcho]

It might be worth knowing that in my experience the tidal strength doesn't quite follow the usual rule of thirds where the flow is strongest halfway between high and low water. I think it is due to flood plains soaking up excess water and letting it go again, but whatever the reason, the ebb tide can be fierce very soon after high water.

 

[Bru]

I live and work on the Crouch and not only that we're in a mud berth so I'm intimate with the vagaries of the tides!

There are no published tidal streams for the river (that I'm aware of at any rate), it's basically a case of what comes in must go out plus the effects of any rainfall on the catchment area of the river.

As already mentioned, forget the rule of thirds. Being a river channel combined with the effect of the river flow means that the flood stream tends to taper off quite early. The tide continues to rise but there isn't as much flow as you might expect. The opposite is true of the ebb which can really shift for an hour or two fairly shortly after high water. The further upstream you are, the more this applies.

One thing I have really noticed this year is that something seems to have changed.

There is a much shorter stand around high water - we used to have anything up to forty five minutes to an hour to get on and off our berth around high water, this year it's been as short as fifteen minutes. And the ebb tide seems to be flowing harder than I recall in the recent past (coming into the Crouch against the ebb the other week we had well over 3 knots of foul tide (at the revs I was running, I'd expect to be doing about 6.5 knots through the water and at times we were making less than 3 knots over the ground). My impression was that we were punching into at least a knot more tide than I'd have expected based on experience of the river

The high tide has frequently failed to make predicted height this year (last year, I could consistently get on and off our berth on a predicted 5.1m tide. This year I've had to wait for 5.3m plus. I have marks on the adjacent pontoon pile made over the last three years and the tide has been coming up anything up to a foot (0.3m to 0.4m) less than predicted more often than not whereas in previous years it rarely failed to make the predicted height

A lot of people on the river believe that the Wallasea Island re-flooding project has significantly altered the tidal characteristics of the river. I'm not sure whether that is true or not but it's plausible (on the basis that creating a new sizeable tidal lagoon must surely alter the tidal flow characteristics of the river)

Another thing we're noticing at Fambridge is that the water is much clearer this year than we're used to. It's normally in the "too thick to drink, too thin to plough" category, absolutely laden with sediment and completely opaque. This year it's been astonishingly clear, at least relatively anyway. No idea why!

 

[stuey_two]

I live and work on the Crouch and not only that we're in a mud berth so I'm intimate with the vagaries of the tides!

There are no published tidal streams for the river (that I'm aware of at any rate), it's basically a case of what comes in must go out plus the effects of any rainfall on the catchment area of the river.

As already mentioned, forget the rule of thirds. Being a river channel combined with the effect of the river flow means that the flood stream tends to taper off quite early. The tide continues to rise but there isn't as much flow as you might expect. The opposite is true of the ebb which can really shift for an hour or two fairly shortly after high water. The further upstream you are, the more this applies.

One thing I have really noticed this year is that something seems to have changed.

There is a much shorter stand around high water - we used to have anything up to forty five minutes to an hour to get on and off our berth around high water, this year it's been as short as fifteen minutes. And the ebb tide seems to be flowing harder than I recall in the recent past (coming into the Crouch against the ebb the other week we had well over 3 knots of foul tide (at the revs I was running, I'd expect to be doing about 6.5 knots through the water and at times we were making less than 3 knots over the ground). My impression was that we were punching into at least a knot more tide than I'd have expected based on experience of the river

The high tide has frequently failed to make predicted height this year (last year, I could consistently get on and off our berth on a predicted 5.1m tide. This year I've had to wait for 5.3m plus. I have marks on the adjacent pontoon pile made over the last three years and the tide has been coming up anything up to a foot (0.3m to 0.4m) less than predicted more often than not whereas in previous years it rarely failed to make the predicted height

A lot of people on the river believe that the Wallasea Island re-flooding project has significantly altered the tidal characteristics of the river. I'm not sure whether that is true or not but it's plausible (on the basis that creating a new sizeable tidal lagoon must surely alter the tidal flow characteristics of the river)

Another thing we're noticing at Fambridge is that the water is much clearer this year than we're used to. It's normally in the "too thick to drink, too thin to plough" category, absolutely laden with sediment and completely opaque. This year it's been astonishingly clear, at least relatively anyway. No idea why!

Thanks Bru, very helpful comments.

 

[Burnham Bob]

Not proven but IMHO the Crouch runs faster than it used to when we started sailing 15 years ago - maybe the breakup of Bridgemarsh island?

 

[gabrue]

Not proven but IMHO the Crouch runs faster than it used to when we started sailing 15 years ago - maybe the breakup of Bridgemarsh island?

Hi to Burnham Bob. Unrelated to this topic, my wife has just bought a Trapper 500 'Lady Pickle' you may know her (the boat not the wife) at Burnham.
I have a couple of questions that you may be able to help with. Would you be able to contact me on here? Thanks gabrue

 

[Lucky Duck]

Hi to Burnham Bob. Unrelated to this topic, my wife has just bought a Trapper 500 'Lady Pickle' you may know her (the boat not the wife) at Burnham.
I have a couple of questions that you may be able to help with. Would you be able to contact me on here? Thanks gabrue

That boat is known to at least a three of us here, will send you a PM

 

[gabrue]

Thanks, we are looking to replace all the cushions inside and I think that BB did this to his Trapper a few years ago

 

[PeterWright]

There's a good reason so little is published about the tidal streams in the Crouch and Roach - it's all to give us locals an advantage over visitors racing here!

Peter

 

[stuey_two]

There's a good reason so little is published about the tidal streams in the Crouch and Roach - it's all to give us locals an advantage over visitors racing here!

Peter

A Burnham resident visiting Tollesbury told me much the same thing some time ago - but with emphasis on how to beat the tide when travelling between the two rivers. Kept the details under his hat!!