• U.S.

Science: Waterboys

3 minute read
TIME

Most citizens east of the Rockies get badly mixed up on their dams and few of them care. But the queer-looking drawing below, in addition to representing bread-in-the-mouths of Californians, shows something oddly unique in man’s continual fretting & fussing with his environment.

The Colorado River Aqueduct will lift a river higher than any river has ever been lifted before. It will divert a billion gallons a day of the copious Colorado River and lift that water 1,600 ft.—a small mountain’s height — and drop it down again 340 miles from where it was.

The people who want the river are, of course, southern Californians who get only 15 inches of rain in an average year. Their greatest waterboy of all time was a Grand Old Man, the late William Mulholland. He fetched them a river from the snowy slopes of the Sierras by way of the Owens Valley Aqueduct ($25,000,000). And when the people of the Los Angeles region promptly multiplied to 3,000,000, he set out to fetch them the Colorado at a cost of $200,000,000. In charge of Engineer Frank Elwin Weymouth, the job gave work to 45,000 men, fun and head aches to no less than 300 engineers. The last tunnel was holed through by blasting last month. Expectations were At the rubble would be cleared by next week, that by next summer Colorado River water would start pouring into Cajalco Reservoir, thence to Los Angeles and twelve other thirsty California towns.

The intake is at Parker Dam on the Colorado River, 155 miles south of Boulder Dam. Five pumping stations raise the stream high enough to get over or through the mountains. Downhill gravity flow takes care of most of the route. There are 38 tunnels totaling 108 miles.

Chief Weymouth and his lieutenants made several contributions to engineering science. They designed special canal grading and lining machines. They proved the efficacy of curved steel I-beams for tunnel supports. And they learned how to weld steel pipe an inch thick.

In the toughest tunnel, under the San Jacinto mountains, the engineers ran into inflows of ground water up to 15,800 gallons per minute. According to the superintendent on this job, “water pressures as high as 600 lb. per sq. in. caved in headings or brought down the arch; water had to be pumped out against an 800-ft. head through a shaft that was flooded repeatedly while the work was under contract. . . . Repeated relocation of portions of the tunnel were necessary.” When the engineers finally holed through San Jacinto tunnel, they were calling it, with commingled irritation and pride, “Old San Jack.”

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