Watchet Silt and Mud Group report mud removal Success

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Been reading on Google about the trial in August of the latest mud removal system to be tested at Watchet. It appears to be a great success and much cheaper than anything else. It involves air lines laid on the bottom with the air stirring up the mud so that it drifts out of the harbour on the ebb, Similar to the barge that was there but this time a permanent fixture that works all the time on the ebb tide. Fingers crossed this could be the solution. Google Watchet Mud and you'll find the details.
 
Let's hope it works and remains a permanent solution

Would love to start using Watchet again but not happy sitting in mud, no matter how gloopy it is
 
When a similar (water jet) system was proposed several years ago, the Environment Agency kicked up a big fuss. At the time it was pointed out to them very firmly that no-one was creating any new mud, just wanting to emulate the normal foreshore transport system of keeping the stuff moving along the coast.

Glad to hear that a simple solution looks as if it has been found.
 
I've read the comment on the other thread, saying the "new" method just made holes. I'm not surprised as the pipe dredgers are normally used on underwater archaeological sites. A good bit of kit for the right job but I can't see much use for it in Watchet.
After visiting the marina many times and reading a number of reports on the mud, I came up with my own suggestion.

The stream that comes down off the moors is tidal at the tide end. If a dam was added to hold the level at high tide, it would give a reservoir large enough to produce a large amount of water to pump into the marina. If pipes with a series of jets were laid on the floor of the marina, the fresh water could be used to agitate the silt so it stayed in suspension whist the gate is open. The following things would need addressing/testing:
1. The dam may need to lift/drop when the stream is in flood. (Having a sump would still provide enough water)
2. The best time, of the tidal cycle, for the pumping/agitation would need to be established.
3. The marina may need to be split into sections, which could be agitated one at a time, if the water supply/pumps are too small.

Many people have said that the harbour didn't silt up when it was fed by the stream. This addresses that, in a controlled way. It may also help to have some compressed air added in certain areas. Care would need to be taken as vessels lose buoyancy it there is too much air in the water!
I have some experience of water jets, in industrial process equipment and they don't penetrate far through standing water. The design of the the jets and the jet arrays would be crucial. The key being to produce turbulence.
The whole testing and design process would be perfect for a university project or someones PhD Thesis.
Allan
 
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Popped into the office today..... got shown a picture of the new dredger! Yay I thought....



poo I thought as it was literally just the jigged up & painted mud / water injection bit. Really? After a year of build all you can show a customer is a picture of a 8 inch pipe with 50 holes in it?

Progress is slow.....
 
The management company are ultimately property developers. Banking their profits will be high priority but a dredger will be low down on their list of priorities.

I wouldnt be so cynical if I hadnt been disappointed so often. anyway a dredger doesnt actual solve the problem of the p poor earlier development diverting river outside the harbour, just puts a bandage on it
 
I don't thing diverting the small river back into the harbour would solve the mud problem even if they could do it.
It needs a full dredge and get it back to bedrock then they would be full of visitors to make a profit and the would also spend in the local shops
 
The word on the street (in the mud?) is.....

The marina operators lease has always only allowed space for something like 20 boats on the quayside. Plus rights to operate a crane, plus some car parking space formula. The yard facility will be kind of in the area it is now, with the new development to the south end (at the entrance to the quay).
New development will include new marina facilities.


Diverting the river back will never stop the mud issue -in years gone by it was only really usable as a mechanism (think conveyor belt) for transporting agitated mud out into the channel. Yes it cut furrows, but not really dredging.


There is a mud working group made up of various persons with the skills/knowledge/ drive to try and find a solution to the mud. The marina are meant to be soon launching the new WID dredger - although it is seriously overdue. This is a Watchet version of the machine used by Cardiff Marine Services, with adaptations. Once this is in and if proven as a method to regularly 'agitation dredge' the upper soft mud levels, this should mean that if a significant dredge (buckets and spades type) was undertaken, then water depth could be maintained. Unlikely that the WID could cost effectively dredge the whole place - that was tried a few years back with Vaan Oord Dredging, with no real success.

A significant dredge will be very costly and therefore funding will likely have to be sought - but first they need to prove they can maintain an acceptable water level, and that it won't just fill up with mud again and therefore potentially money wasted.


Yes history shows that the original marina build was pretty much of a balls up in regard to dealing with the mud. The original developers were meant to have put in a solution, but didn't. Then there was a falling out with the district council landlords, so they left.


Unfortunately Watchet is so much more of a headache than just a place with a mud problem. Think how long the tidal gate took to get reinstated. Politics politics!
 
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