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3) Pre-cast concrete lining
4) Soil cement lining
5) Pre-fabricated light membrane lining
Concrete lining is very costly and used only on exceptional circumstances keeping
in view of the economic viability.
Piped Water Distribution System
Canal water distribution system is basically meant for irrigation system,
particularly major and medium irrigation projects and may in certain cases for
minor irrigation projects. Major irrigation projects have command area of more
than 10,000 ha; Medium Irrigation Projects have command area between 2000
ha and 10000 ha; Minor irrigation projects have command area of 2000 ha. and
below. While major and medium irrigation projects can hardly think of using
piped distribution system because of high discharge and high cost involved, in
many Minor irrigation projects, piped water distribution system is used. Piped
water distribution is also used for the industry and also for water supply for
drinking water purposes.
Classification of Piped water distribution
Cement Concrete Pipes
Cement concrete pipes (with or without reinforcement) are used in many areas
for distribution of water as they have many advantages over other
materials like metal pipes or asbestos pipes, as if properly used they are not
susceptible to rusting or incrustation. However, such pipes can not be laid in
highly alkaline or saline soils. Highly acidic or alkaline water or water with wild
hardness or having sediments are also not suitable. These types of pipes are
cheaper and durable.
RCC Pipes
Unreinforced pipes are not generally used for diameters above 450mm.
Reinforced concrete pipes are made with steel fabric or wire cages in single or
double layers inside and outside for gripping the concrete. Such pipes are used
where the pressure is low and seldom exceeds 50m. A surge pipe or vacuum
chamber is used near the pumpset to prevent sudden shock when the pump is
stopped.
