Skip to main content

Firefighter Math: Table 3.1 Water Handling Unit Estimations

Description
ID = Inner Diameter		 Rounded Values
Used in
U.S. Measure
Field Estimations
GOOD TO MEMORIZE
ID = Inner Diameter
Volume (Capacity)		 U.S. Measure
Volume (Capacity)
One hose length    
1-1/2-in ID x 100 ft 9 gal 9.2 gal
1-in ID x 100 ft 4 gal 4.1 gal
3/4-in ID x 50 ft 1 gal 1.2 gal
5/8-in ID x 50 ft 1 gal 0.8 gal
     
  Weight Weight
1 gal of water at 20°C 8 lb 8.3 lb
     
  Pressure Pressure
1 ft of water head (1 in2 column of water) 0.5 psi 0.434 psi
Atmospheric pressure 15 psi @ sea level 14.7 psi @ sea level
1,000 ft increase in elevation 0.5 psi decrease in atmospheric pressure 0.5 psi decrease in atmospheric pressure
     
  Draft (lift) Draft (lift)
1 in of mercury 1 ft 1.134 ft
1,000 ft increase in elevation 1 ft loss 1 ft loss
Maximum theoretical lift 34 ft 33.9 ft
Maximum attainable lift with new pump 29 ft * 29.4 ft
Maximum practical attainable lift 22 ft 22.4 ft

 

* Pump lift varies with pump efficiency, which decreases proportionately to the hours of use.

NWCG Latest Announcements

Intermediate Faller (FAL2) Position Task Book Update

Date:  July 24, 2026
Questions? 
Please contact: Tree Felling Subcommittee

NWCG Operations Management Committee (OMC) has issued an update to the NWCG Position Task Book for Intermediate Faller (FAL2), PMS 311-91. To ensure clarity for both trainees and evaluators, the updated FAL2 Position Task Book (PTB) explicitly states who is authorized to sign off on your tasks:

“Evaluators must be qualified as a FAL2, or an Advanced Faller (FAL1).”

If you are currently working out of a previously published version of the FAL2 PTB, you do not need to restart. However, OMC highly encourages you to take the following step to prevent any confusion in the field:

  • Print and replace the updated evaluator information page (page 2) in your current physical PTB.

References:

Intermediate Faller (FAL2) Position Page

RMC Memo 26-01: Transition Plan for Implementing Updates to Intermediate Faller (FAL2) Position Qualifications

NWCG Position Task Book for Intermediate Faller (FAL2), PMS 311-91

Equipment Advisory 26-001: Potential Front Driveline Joint Failure on 2018 and Earlier Ram Pickups

Date:  July 10, 2026
Questions? 
Please contact: Equipment and Technology Subcommittee

The Logistics/Equipment Management Committee (LMC) has released Equipment Advisory 26-001: Potential Front Driveline Joint Failure on 2018 and Earlier Ram Pickups. This advisory highlights multiple U.S. Forest Service regions reporting front driveline joint failure incidents.

This advisory recommends firefighters and fire managers to: 

  • Follow all Ram-issued inspection, maintenance, and service guidance for front driveline joints. 
  • Consider installing a driveline loop. 
  • Coordinate with fleet managers and service providers to determine the most appropriate driveline loop kit for each pickup.

For further details, please refer to the complete advisory.

References:

Equipment Advisory 26-001: Potential Front Driveline Joint Failure on 2018 and Earlier Ram Pickups

Technical Service Bulletin: 03-002-21

NEW! NWCG Standard Operating Procedures, PMS 900

Date:  July 9, 2026
Questions? 
Please contact: NWCG Staff

NWCG is excited to announce the publication of the NWCG Standard Operating Procedures, PMS 900.

The new publication establishes general, consistent, and uniform standards for conducting business with the National Wildfire Coordinating Group.

References:

NWCG Standard Operating Procedures, PMS 900

Quarter Four Materials for the 2025-2026 Wildland Fire Leadership Campaign Now Available

Date:  July 8, 2026
Questions? 
Please contact: Leadership Development Subcommittee

NWCG is excited to announce that Fourth Quarter materials for the 2025/2026 Wildland Fire Leadership Campaign are now available. This annual initiative offers all students of leadership and wildland fire management an opportunity to engage with essential leadership skills and knowledge needed to lead effectively in dynamic environments.

Quarter Four materials focus on Leadership Level 4: Leader of Leaders (Provide Direction). Leadership Level 4 is where you are setting the conditions for others to do things well, even when you are not present. This quarter focuses on equipping experienced leaders with skills to provide direction, build trust across teams, and foster strong decision making. 

References:

2025/2026 NWCG Leadership Campaign - Leadership Levels

Wildland Fire Leadership Development Program

Leadership Development Subcommittee