Fire hydrant installation consists of a system of pipe work connected directly to the water supply main to provide water to each and every hydrant outlet and is intended to provide water for the firemen to fight a fire. The water is discharged into the fire engine form which it is then pumped and sprayed over fire. Where the water supply is not reliable or inadequate, hydrant pumps should be provided to pressurize the fire mains.
A water supply for a fire hydrant system can be derived from a reliable source of water such as; street mains, static water supply such as a tank or dam. Water storage must also include a facility for automatic replenishment (make-up water) due to losses from evaporation, leakage, periodic testing, etc. The capacity or volume of the water supply or storage must also be taken into account as part of the hydraulic analysis.