Water supply

Water Supply Decision Tool

Compare required flow against hydrant, relay, tender shuttle, and tank water so the engineer can quickly see whether water supply is enough.

Engineer Tools Hub

Water supply decision flowchart showing hydrant supply, relay pumping, tender shuttle, and tank water only options. — This water-supply decision board helps match the fire flow need to the right supply strategy.

Inputs

Required fire flow (GPM)

Available hydrant flow (GPM)

Relay supply available (GPM)

Tender shuttle sustained flow (GPM)

Tank water (gal)

Reserve to keep (gal)

Use the best known available supply. Do not double-count the same water source.

Decision

Total sustained supply

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Margin

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Tank-only time

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Recommendation

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Decision guide

If sustained supply is below required flow, the engineer should communicate the limitation and consider a second supply line, another hydrant, relay pumping, tender shuttle, or reduced flow until supply improves.