Engineering, 19.02.2021 17:00, uchechukwueigwe

A lake has a surface area of 1.00 x 10^8 m2. Phosphorus enters the lake from a discharge pipe out of a sewage treatment plant. This effluent has a flow rate of 1 m3/s and the phosphorus concentration is 2.0 mg/L. There is also a clean river with flow rate 50.0 m3/s into the lake (the water level of the lake is steady, so presumably there is enough outflow to equal the inflow of water). The phosphorus settling rate is 10.0 m/yr. a. What is the steady-state (or average) phosphorus concentration in the lake?
b. By what percentage must the sewage treatment plant reduce the concentration of phosphorus in its discharge to keep the lake below the eutrophication limit?

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A lake has a surface area of 1.00 x 10^8 m2. Phosphorus enters the lake from a discharge pipe out of...