Question

A town requiring 2.0 m3/s of drinking water has two sources, a local well with 15 g/m3 nitrate (as N) and a distant reservoir with 5 g/m3 nitrate (as N). What flow rates of well and reservoir water are needed to meet the EPA drinking water standard and minimize the use of more expensive reservoir water

Answer 1

Explanation:

Drinking water requirement in town 2.0 m^3/s of water per second

nitrate in local well  nitrate per 15 $\mathrm{m}^{3}$ of water

nitrate in distant reservoir $=5 \mathrm{~g} / \mathrm{m}^{3}$

Let the flow rate of well

flow rate of reservoir $=y m^{3} / s$

Drinking water requirement is $45 \mathrm{ppm}$ or $45 \mathrm{~g} / \mathrm{m}^{3}$

therefore, the total flow of drinking water