Tanker (Water Shuttle) Flow Capability
Sustained rural shuttle flow: usable = nominal x fraction (ISO ~0.90).
Example
You enter
- Nominal tank volume (gal) 3000
- Usable fraction (ISO ~0.90) 0.9
- Number of tankers 3
- Cycle time (min: fill + dump + round-trip) 12
You get
- Usable volume per tanker 2700 gal
- Sustained shuttle flow 675 gpm sustained
Checked against published worked examples from: ISO PPC hauled-water credit / NFPA 1142.
Details, formula, and sources
Scopeshuttle_flow = usable x tankers / cycle (fill + dump + round-trip). The fleet flow is capped by the slowest link -- usually the fill or dump site, not the tank size -- so a fourth tanker adds nothing if the fill pump cannot turn it around. A planning aid, not incident command.
Formula or tableusable_gal = nominal_tank_gal x usable_fraction; shuttle_flow = usable_gal x tanker_count / cycle_time_min (cycle = fill + dump + 2 x travel).
Source and editionISO PPC hauled-water credit / NFPA 1142 water shuttle, by name.
Free accessThe water-shuttle relations are public fire-service training material; the fill-site pump capacity and the operation govern the actual delivery.
What governsEstimate. AHJ and licensed professional govern.
API field namesnominal_tank_gal, usable_fraction, tanker_count, cycle_time_min, usable_gal, shuttle_flow_gpm
- Usable credit ISO credits about 90% of nominal tank volume as usableISO PPC hauled-water credit
- Bottleneck sustained flow is capped by the fill/dump site, not the number or size of tankersNFPA 1142 water shuttle