Changes

To reduce operating pressures, it is sometimes necessary to introduce break-pressure tanks, which are usually made of concrete or ferrocement. If such tanks are used, the hydraulic gradient starts again at tank water level. If suitably sized, these tanks can be used within the system as storage tanks to meet peak demand.

Capacities of tanks should be 10 to 100 cubic metres, depending upon the size of the population to be served. Various materials have been used to construct them: masonry, reinforced concrete, concrete clockwork, ferrocement, galvanized mild steel, and GRP panels. In flat areas, tanks may have to be elevated on blockwork support structures. Tanks are roofed and, typically, are provided with a float controlled inlet valve, twin outlet pipes with stop valves, a scour pipe at low level for emptying and cleaning out, and an overflow pipe led far away from the tank.