On a split hose lay, what water source does the initial attack engine use to fight the fire until the supply engine is ready to pump?

In a split hose lay operation, the initial attack engine often relies on its onboard water supply, which is typically known as the booster tank. The booster tank is a built-in reservoir that allows the engine to have immediate access to water, enabling firefighters to begin their attack on the fire quickly while waiting for a supply engine to establish a reliable water source.

This immediate use of the booster tank is crucial in firefighting operations, as it provides the first line of defense against a fire before additional water supply lines are set up. The use of a booster tank ensures that firefighters can initiate an effective response without delay, which can be critical in containing and suppressing the fire before it spreads.

Other water sources, like building sources or drafting from a static water supply, may take more time to establish and are not as readily available for the initial rapid response that is often necessary in fire situations. Thus, referring to the booster tank highlights the importance of having an efficient water supply readily available on the fire engine.