Ming the Merciless
There is no mercy
- Location
- Inside my skull
Answering my own question ... I suppose if the outflow were from the bottom of the reservoir then the water flow would be violent and somebody would have to open the sluice gates.
Now I can see the reason for those scary overflows in Ladybower!
View attachment 479003
That's not an overflow, it's a worm hole to another Universe.
It's a kind of hybrid - 53,000 tonnes of clay core but supported by an embankment of 3.4 million cubic metres of rock. That shouldn't shift in a hurry, plus it has a bellmouth overflow within the reservoir, not a spillway as such, 10m below the top of the dam embankment.