treatment plant may have pumps in it
pumps to move the water to elevated
only to move the water through the
storage tanks from which the water
plant. This type of system will be
moves
by
gravity
through
the
rare because of the very favorable
distribution system.
Because the
elevation
relationship
required
water moves through the distribution
between source, storage, and user.
lines
due
to
gravity,
continuous
pumping to storage is not necessary.
(2) Direct
pumping.
Direct
A combination system may have a layout
pumping
systems
have
no
elevated
similar to that shown in figure 10.
storage, so the water must be pumped
to the ground storage reservoir and
b. Classification
by
pipe
pumped from the reservoir to the user.
arrangement.
The
network
for
Since the user may need water at any
distribution should be arranged with
time, continuous pumping is necessary.
large primary mains feeding smaller
secondary pipes.
Branches or feeders
(3) Combination of gravity and
carry water from mains to service
pumping.
A combination of the two
connections where service pipes carry
systems mentioned above is probably
water from the branch to the building.
the
most
common
system.
This,
generally, will utilize low-lift pumps
(1) Loop system. The loop system is
to move water from a source through
one in which the ends of all the supply
the treatment plant, and high-lift
Figure 10. Layout of a combination water system.
3-12