Layout of Water Distribution system

There are two types of layout.

Dead end or tree system
Grid iron system

Dead end or tree system

It is the system in which each street or block is supplied separately from the main. So there is end of system at each end of the block.

Advantages

This type of system is good for a city which has been developed haphazardly.
As it required less number of valves so it is economical.
This type of system is easy to construct.

Disadvantages

This system is less desireable due to following reasons.

Large areas are cut off during repairing.
When tap is not opened for a long time, baterial growth may take place.
When tap is not operated for a long time, water may be contaminated.

Grid iron system

In grid iron system, the whole distribution system is interconnected. So the water remains in circulation and there is no contamination of water. Because water does not stand still at any point and it continues circulation.

Advantages

In this system, as the whole distribution system is interconnected, water can reach from more than one directions.
It provides better quality of water.
During its repairing lesser area is cut off.

Disadvantages

The main problem in grid iron system is that a lot of valve to cut off a small area in case of accidental hazards.
This system is difficult to design.
The network of pipes forming loops in possible only in well planned cities.

Usually the system in cities is a combination of dead end and grid iron system.