Which is characteristic of low head dams? ...?

Question

Which is characteristic of low head dams?
a. They pose hazards both above and below dams.
b. They pose few hazards to inboard-powered boats.
c. They may be crossed safely at a 45-degree angle to their faces.
d. They usually have strong recirculating currents just above them.

Answer 1

a. They pose hazards both above and below dams.

"Once primary energy sources, the Fox River's low-head dams that churn cyclone-like waters have become a source of death for more than a dozen people in recent years."

"Among the possible recommendations would be to construct an angled rock ramp or to place boulders at the bottom of the dam to break the deadly spin of the water, known as a "boil" or "washing-machine effect."

Answer 2

None of the above. They pose no particular hazards, nor crossing requirements.