WATER TREATMENT AND PURIFICATION
As a Utilitiesman, you are responsible for
ensuring that an adequate supply of safe
water is available for domestic and fire
protection uses. In meeting this responsibility
you must consider several factors, such as the
selection of a water source, ways to develop
the water source, contaminants you may
encounter, and methods you can use to remove
these contaminants. In this chapter, each of
these considerations is discussed.
WATER SOURCE SELECTION
You must consider three factors for a water
source: quantity, quality, and reliability.
Water sources developed for military use
are referred to as water points. Water points
are classified as follows:
1. Surface water (streams, lakes, and rivers)
2. Groundwater (wells and springs)
4. Rain, snow, and ice
When selecting a water source, you must
consider the amount of water available and
what the demand is for water.
The amount of water that collects in any
surface source depends on the amount of
precipitation, the size of the drained area,
geology, ground surface, evaporation,
temperature, topography, and artificial controls.
The available water at a source can be
estimated by using some simple calculations.
To calculate the quantity of water (gallons
per minute) flowing in a stream, use the
6.4 x A x V.
Quantity of water in gallons per
A c o n s t a n t - T h e r e a r e 7 . 5
gallons of water per cubic foot.
However, because of error in
stream measurement, 7.5 has
been reduced to 6.4.
The area of the stream in square
feet obtained by multiplying the
width times the average depth of
The velocity of the stream in feet
per minute obtained by measuring
the time it takes a floating object
to travel a known distance.
An example of this calculation would be a
stream having an average depth of 2 feet and a
width of 16 feet, and a twig is noted to flow at
13.3 feet per minute. To find the amount of
water flowing in the stream, you should work the
equation as follows:
Q= 6.4 x A x V
Q= 6.4 x (2 x 16) x 13.3
Q= 6.4 x 32 x 13.3
Q = 2,723.84 gpm
To calculate the quantity of water in a lake
or pond having little or no runoff, multiply the