Solve Example 6. 4 by using dynamic programming.

A dam supplies water to a city and downstream agricultural lands. The average monthly domestic and irrigation demands and the monthly reservoir release in a dry year are as shown in Table 6. 16. The prices of water for domestic and irrigation uses are $90,000 and

$10,000 per million cubic meters, respectively.

• Formulate the problem for optimizing the water allocation from this reservoir.

• Solve the problem using linear programming.

Data from example 6. 4 Calculate

(a) the number of kilograms of chlorine needed per day and

(b) the capacity of the contact tank in the water treatment plant for the city of 100,000 people given in the previous example.
The chlorine demand is 1 mg/L. It should be noted that at least 1. 2 mg of chlorine must be added to every liter to overcome the chlorine demand of 1 mg/L and produce a free available chlorine concentration of 0. 2 mg/L.

TABLE 6.16 The Average Monthly Domestic and Irrigation Demands and the Monthly Reservoir Release of Problem 35 (Numbers are in Million Cubic Meters) Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Domestic 8 8.5 8.5 9 9 9.5 9.5 10 9.5 9 8.5 8.5 Irrigation 0 0 20 50 55 70 70 65 20 10 0 0 Release 25 27 40 48 60 42 25 17 14 18 20 25