Mt. Pleasant Pyramid | 1913-02-14 | Page 6 | Official Irrigation Terms

OFFICIAL IRRIGATION TERMS "Second-Foot" Defined by United ' States Geological Survey Used as Fundamental Unit. "Second-foot," as defined by the United States geological survey, is an abbreviation for cubic foot per second and is the unit for the rate of dls-charco dls-charco of water flowing in a stream one foot wide, one foot deep, at a rate of one foot per second. It Is generally used as a fundamental unit in measurements meas-urements of stream flow. "Second-feet per square mile" is the average number of cubic feet of water flowing per second from each square mile of area drained, on the assumption assump-tion that the run-off is distributed uniformly both as regards time and area. An "acre-foot" Is equivalent to 43,-560 43,-560 cubic feet, and is the quantity required re-quired to cover an acre to the depth of one foot. The term is commonly used in connection with storage for irrigation irriga-tion work. One second-foot flow equals 7.48 gallons gal-lons a second, 448.8 a minte, or 646,-272 646,-272 gallons in 24 hours. As a California Cali-fornia "miner's Inch" equals 0.187 gallon gal-lon a second, there are 40 California miner's inches in one second-foot.