Water? OK, everyone know's water's wet but in the UK we either have too much or not enough?

A couple of things struck me. 1/ We've all seen pics of the low levels in reservoirs (we have, haven't we?) but while they're low, why don't they clear all the mud, debris and shores to increase the capacity for when the levels return to "normal"?

2/ Planting more trees? Hmmmm, a conundrum there? OK, so trees improve the air quality but they "drink" a lot of water. Only one large tree consumes 40 gallons of water a day. That water has to come from somewhere?

So, what's your thoughts on those two points?