The Design Of Potable Water Supply System For Institutional Setting
[A CASE STUDY OF KWARA STATE POLYTECHNIC PERMANENT SITE]

The advantages of Grid iron system are:
1.    As water is supplied from both the sides at every point, very small area will be affected during repair.
2.    Since water reaches every point from more than one route, the Friction losses and the sizes of the pipes are reduced.
3.    All the dead ends are completely eliminated, therefore the water remains in continuous flow and there is no stagnation and chance of pollution is reduced to minimum.
4.    In case of fire, more quantity of water can be diverted towards the affected area, by closing the valves of nearby localities 
2.3.3    Circular or Ring System:   
This system below can be adopted only in well planned locality of cities. Figure 6 shows that in this system each locality is divided into square or circular blocks and the water mains are laid around all the four sides of the square or round the circle. This system requires many valves and more pipe length. This system is suitable for towns and cities having well planned roads.

2.3.4 Radial System:
This system is not adopted in Nigeria, because for this system as observe from Figure 7 below the roads should be laid out radially from the center. This system is the reverse of ring system. The entire district is divided into various zones and one reservoir is provided for each zone, which is placed in the center of zone.