On Thu, 25 Sep 2014 16:20:48 +0100, Tim w wrote:

A tidal lagoon in the Bristol Channel would fill with mud in a year.

Properly designed you use the outgoing tide to flush it clear every
so often. Just like they used to flush Bristols Floating Harbour
partly by tide and partly by letting more of the Rivers Frome and
Avon flow that way instead of along the New Cut.

Doing the whole Estuary would just be an even more monstrous **** up.

That would present far greater flushing problems.

--
Cheers
Dave.