Relay Pumping is a technique of using multiple pumps in series in order to move water over longer distances. A hose can tolerate only a certain pressure. Friction loss reduces the water pressure as the hose gets longer, so that a given hose can only move water so far.
If another pump is used to reboost the pressure, then the water can move farther.
This process can be used with an unlimited number of pumps.
The only problem is that if the pumps are not synchronized in operation, "water hammer" can destroy the hose run.
Today, relay pumping is controlled by radio communication between all of the pump operators.
When there are more than a few operators, the radios don't allow for precise synchronization of the pumps.
The following sections will show how a digital network supported by a wire pair in the hoses can prevent "water hammer".
Digital relay pumping would allow for very long relays which can bring water closer to the fires.
Digital relay pumping can also be used to deliver water to areas whose water mains have been destroyed by EARTHQUAKES.
The water delivered can be used to fight fires caused by the earthquake, and also to supply drinking water to the population.
The figure below shows how a tracked vehicle can deploy a series of pumps with hoses to produce a Digital Relay in rugged terrain.