why don’t dam operators dredge in the dam lake during dry spells (or times when the water levels are too low) to expand the dam’s water capacity?

Question

Because I think it’ll be nice to have more water stored

In: Engineering

Answer 1

Let’s see.

A modest reservoir is 100,000 acre-feet. Lets say you want to increase that by 10%.

That’s 10,000 acre-feet of mud, or (x1233) about 12,330,000 cubic meters. At 10 per truck, that’s 1.2 million truckloads, weighing about 30 million metric tons.

Now picture a big reservoir, like Shasta in California. 4,555,000 acre-feet.

There’s a good reason why reservoirs are built in naturally occurring valleys.