Quiz 1 with Answers for Hydrologic Principles | ERS 100, Quizzes of Environmental Science

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Answers Quiz 1 (example Quiz) ERS 100 Question 1) Qin - Qou- E = L = AS/At There is no change in height, so AS = 0 L = Qin - Qoue - E Based on evaporation values, the area under the curve of “Pan evaporation vs. Time” will yield the evaporation. This turn out to be approximately 0.627 inch/day = 5.23 * 107 fi/day We have to adjust for these data using a pan coefficient of 0.7 for differences between pan and open water surface measurements. The area that evaporates is both the area of the wetland and the area of the prefilter Wetland area = 8 ft x 20 ft= 160 #” Pre filter area = 4 ftx 2 ft=8 ft” Total evaporative rate = 168 * 0.7 * 5.23 * 107 =0.7 * 8.78 fi'/day = 46.0 gpd L= Qin - Qou - E = 75 - 8 - 46 = 21 gpd (gallons per day). Since a flowrate is asked for, the length of time (3 days) is not important !! Question 2) To calculate the pressure, we need to find the height of the water column above the port location, Total depth is 4 feet, and the port is 0.5 feet above the bottom of the wetland system. The total column of water above the port is 3.5 feet. The pressure (in psi) can be calculated as: p=h*y where h is in [m]. h=3.5 * 0,304 =1.06m