Handbook of Civil Engineering Calculations

FIGURE 4. Demand curve for a typical week for a city of 100,000 population. (Babbitt,
Doland, and Cleasby.)

This procedure is the work of Harold E. Babbitt, James J. Doland, and John L. Cleas-
by, as reported in their book, Water Supply Engineering, McGraw-Hill.

FINDING THE DRAWDOWN OF A

DISCHARGING GRAVITY WELL

A gravity well 12 in (30.5 cm) in diameter is discharging 150 gal/mm (9.5 L/s), with a
drawdown of 10 ft (3 m). It discharges 500 gal/mm (31.6 L/s) with a drawdown of 50 ft
(15 m). The static depth of the water in the well is 150 ft (45.7 m). What will be the dis-
charge from the well with a drawdown of 20 ft (6 m)?

Calculation Procedure:

1. Apply the Dupuit formula to this well
   Using the formula as given in the previous calculation procedure, we see that

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Per

cent

of

average

doy