Clear Lake has a surface area of 708,000 m2 (70.8 ha). For a given month the lake has an inflow of 1.5 m3/s and an outf1ow of 1.25 m3/s.  A +1.0 -m storage change or increase in lake level was recorded. If a precipitation gage recorded a total of 24 cm for this month, determine the evaporation loss (in cm) for the lake. Assume that seepage loss is negligible.

6. Runoff from a 200 mile² catchment drains into a reservoir than has an average surface area of 4000 acres. The reservoir is to be used for municipal water supply. Annual rainfall over the watershed is 40 inches and the annual runoff is 2 inches. Evaporation from the reservoir averages 40 inches per year. If the surface area of the reservoir is roughly constant with depth, how much will the reservoir depth change in one year?

A drainage basin has a area of 7322 km2. The average annual precipitation for this area is 909 mm. The average surface water flow at the outlet of the catchment is 21.4 x 108 m3/year and the average groundwater flow out of the basin is 94.6 mm/year. Assume trailing zeros are significant if present. Determine the annual average evaporation in mm/year. (give your answer to one decimal place)