Question

The Hoover Dam backs up the Colorado River and creates Lake Mead, which is approximately 115 miles long and has a surface area of approximately 225 square miles. If during flood conditions, the Colorado River flows into the lake at a rate of 45,000 cfs and the outflow from the dam is 8,000 ft3/s, how many feet per 24-hour day will the lake level rise

Answer 1

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Answer:

0.510 ft per 24-hour period

Explanation:

We can first find the change in volume in a day:

(45,000 cfs -8,000 cfs)×(3600 s/h)×(24 h/day) = 3.1968×10^9 ft³/day

The area in square feet is about ...

(225 mi²)×(5280 ft/mi)² = 6.27264×10^9 ft²

Then the rate of change of height is ...

h' = ΔV/A = (3.1968×10^9 ft³/day)/(6.27264×10^9 ft²) ≈ 0.510 ft/day

For the given flows, the lake level will rise about 0.510 feet per day.