MIL-HDBK-1005/7A
Change 1, 24 January 2001
2.2.1.2
Controlling Demands. All demands will be multiples of
the average demand, expressed as gallons per minute (gpm) or
gallons per day (gpd). The average demand, in gpd, should be
calculated by Equation (1):
EQUATION (1):
Avg demand in gpd = gpcd x design population x
growth factor
Use the following growth factors in equation (1):
a) Large systems (5,000 population o r greater), 1.25.
b) Small systems (populations less than 5,000), 1.50.
This equation must be performed for each use category shown in
Table 2, and the results must then be added together to
determine total average demand.
Other controlling demands shou ld be evaluated by
Equation (2): Demand = avg demand in gpd x K
using the following data for the coefficient, K:
COEFFICIENT K
UNITS OF
POPULATION
POPULATION
DEMAND
DEMAND
<5000
>5000
Maximum Day Flow
Gpd
2.25
2
Maximum Hour Flow
Gpm
4.0/1,440
3.5/1,440
Instantaneous Peak Flow
Gpm
5.0/1,440
4.5/1,440
The designer may make allowances, as deemed necessary,
for small activities where all or nearly all demand occurs
during working hours.
If a planned buildup or population decre ase can be
foreseen, this change should be taken into account.
6
Previous Page
