It has been proposed to solve the water problem in Los Angeles by importing water from the mouth of the Columbia River, where vast amounts flow into the sea. One way to do this would be with a pipeline and pumping station. Both ends of the pipe are at sea level, so the only pumping cost would be the cost of overcoming the friction loss. The pipe length would be about 1000 mi. Assuming that we want to move 10⁷ acre-ft a year (1 acre-ft = 43,560 ft³), estimate the horsepower of pumps required. State your assumptions.