[uncbob]

Hydro systems are extremely simple...the water flows through the turbine, spins the blades on the generator...and voila, power

Intakes get clogged by trees -debris gets into the intakes etc--turbines blow out through poor maintenance ?????

[SonOfDarkSkies]

Modern penstock intakes are deep underwater and a well-shielded. Additionally, if one penstock were to fail, there are many others that would continue to run.

The Itaipu Dam is a modern marvel (it was named one of the Seven Wonders of the World by American Society of Civil Engineers in 1994--see photo below).