ANDY Walford, (Evening News, December 12) misses the point about dredging the river.

He talks of the hydraulic gradient controlling speed, static amount of water and lifting North Wales. What he fails to mention is friction.

The first three feet of water on the river bed is affected by friction and this where the saying "still waters run deep" comes in, for a fast current lurks beneath the surface.

Instead of lifting North Wales, it would be better to deepen the Bristol Channel.

Seeing how slow the river falls and is affected by the tides - this is where the main problem lies.

M SIMPKINS,

Fernhill Heath,

Worcester.