Size temporary containment for a detected water leak using the measured leak rate, expected response time, and a safety allowance. The calculator estimates the captured volume, recommended storage capacity, and how long the selected tank can hold the flow. Use it for emergency planning, portable tank selection, and response procedures—not as a substitute for code-required secondary containment.
The recommended capacity is the minimum usable volume implied by the entered scenario. Compare it with the tank's usable—not nameplate—capacity and allow for freeboard, access, and local containment rules.
This planning estimate assumes a steady leak rate. Pulsing flow, rainfall, foam, solids, or required freeboard may increase actual capacity needs.
At 25 gpm for 90 minutes, the leak produces 2,250 gallons. A 20% allowance adds 450 gallons, so recommended usable storage is 2,700 gallons. A 3,000-gallon tank provides 120 minutes of holding time.
Multiply the leak rate by the expected isolation time, then add a safety allowance for uncertainty and delays.
No. Enter the usable capacity after subtracting required freeboard and any unusable heel volume.
Use a conservative average or split the event into time segments and add their volumes.
No. Applicable permits, fire codes, environmental rules, and facility standards may require a different capacity.
Holding time equals usable tank capacity divided by the continuous leak rate.
| Variable | Meaning | Unit |
|---|---|---|
| Leak rate | Continuous detected flow | gpm |
| Response time | Time until isolation | minutes |
| Safety allowance | Added volume for uncertainty | percent |
| Tank capacity | Usable available volume | gallons |