Essentials of Fire Fighting,
5th Edition
Chapter 12 — Water Supply
Firefighter I
Chapter 12 Lesson Goal
• After completing this lesson, the
student shall be able to make hydrant
connections and draft from a static
water source according to the authority
having jurisdiction (AHJ).
Firefighter I
12–1
Specific Objectives
1. Describe dry-barrel and wet-barrel
hydrants.
2. Discuss fire hydrant marking and
location.
3. Summarize potential problems to look
for when inspecting fire hydrants.
(Continued)
Firefighter I
12–2
Specific Objectives
4. Explain the process of fire hydrant
testing.
5. Discuss alternative water supplies.
6. Discuss rural water supply operations.
7. Operate a hydrant. (Skill Sheet 12-I1)
(Continued)
Firefighter I
12–3
Specific Objectives
8. Make soft-sleeve and hard-suction
hydrant connections. (Skill Sheet 12-I2)
9. Connect and place a hard-suction
hose for drafting from a static water
source. (Skill Sheet 12-I-3)
10. Deploy a portable water tank. (Skill
Sheet 12-I-4)
Firefighter I
12–4
Hydrants
• Usually made of cast iron with bronze
working parts
• Must be opened and closed slowly to
prevent damage
Firefighter I
12–5
Dry-Barrel Hydrants
• Installed in areas where
prolonged periods of
subfreezing weather are
common
• Have main valve located
below frost line that
prevents water from
entering hydrant barrel
Firefighter I
12–6
(Continued)
Dry-Barrel Hydrants
• Operation
• Must be completely open or closed to
prevent leaking
• When shutting down, verify that water
left in hydrant barrel is draining out
(Continued)
Firefighter I
12–7
Dry-Barrel Hydrants
• In some areas, hydrants must be
pumped out after each use to prevent
water contamination
• If water is bubbling out of ground,
broken component in barrel is allowing
water to get past drain opening
Firefighter I
12–8
Wet-Barrel Hydrants
• Installed in warmer
climates where prolonged
periods of subfreezing
weather uncommon
• Horizontal compressiontype valve at each outlet
• Always filled with water
Firefighter I
12–9
Fire Hydrant Marking
• Rate of flow from individual hydrants
varies for several reasons
• NFPA® has developed system of
marking hydrants
• Local color-coding may differ from
NFPA®
Firefighter I
12–10
Fire Hydrant Locations
• Decisions usually made by water
department personnel based on
recommendations from fire department
• Should not be spaced more than 300
feet (100 m) apart in high-value districts
(Continued)
Firefighter I
12–11
Fire Hydrant Locations
• Locate hydrant at every other
intersection
• Intermediate hydrants may be required
where distances between intersections
exceed 350 to 400 feet (105 to 120 m)
• Other factors affect location/spacing
Firefighter I
12–12
Hydrant Testing and Inspections
• Responsibility of fire department
personnel
• Firefighters should look for wide array
of items
Firefighter I
12–13
Fire Hydrant Testing Process
• Many departments no longer responsible
for testing
• Most basic test normally conducted is
flow test
Firefighter I
12–14
Flow Test Steps
•
•
•
•
•
Select hydrant
Remove all outlet caps
Inspect outlet threads
Lubricate all outlet threads
Replace all caps except one 2½-inch (65
mm) cap
(Continued)
Firefighter I
12–15
Flow Test Steps
• Connect cap-type pressure gauge to
outlet on second hydrant nearby
• Turn second hydrant on, record static
pressure
• Turn test hydrant on fully, allow water
to flow briefly
(Continued)
Firefighter I
12–16
Flow Test Steps
• Use pitot tube, gauge to measure flow
rate
• Record pitot gauge reading
• Take/record residual pressure reading
from gauge connected to second
hydrant before shutting test hydrant off
(Continued)
Firefighter I
12–17
Flow Test Steps
• Turn off second hydrant, remove gauge,
•
•
•
•
replace cap
Turn off test hydrant
Test for vacuum created by operating
drain valve (dry barrel)
Replace cap on outlet
Repeat procedure with each hydrant
Firefighter I
12–18
Alternative Water Supply
Sources
•
•
•
•
•
•
•
Lakes
Ponds
Rivers
Ocean
Swimming pools
Farm stock tanks
Underground cisterns
Firefighter I
12–19
Drafting From Alternative Water
Supplies
• Process of drawing water from static
source to pumper
• Can use almost any static source of
water if sufficient in quantity, not
contaminated
• Depth of water from which to draft
Firefighter I
12–20
Dry Hydrants
• Installed at static water sources to
increase water supply available
• Usually constructed of steel or PVC pipe
with strainers at water source, steamer
ports to connect to pumper
• Designed to supply at least 1,000 gpm
(4 000 L/min)
(Continued)
Firefighter I
12–21
Water Shuttles
• Involve hauling water from supply
source to portable tanks from which
water may be drawn to fight fire
• Recommended for distances greater
than ½ mile (0.8 km) or greater than
the fire department’s capability of laying
supply hoselines
(Continued)
Firefighter I
12–22
Water Shuttles
• Critical elements
– Fast-fill, fast-dump capabilities
– Water supply officers at fill/dump sites
– Traffic control
– Hydrant operations
– Hookups
– Tank venting
Firefighter I
12–23
Water Shuttles
• Key components
• Dump site
• Portable tanks
(Continued)
Firefighter I
12–24
Water Shuttles
• Ways in which water tenders unload
– Gravity dumping
– Jet dumps that increase flow rate
– Apparatus-mounted pumps
– Combination of these methods
(Continued)
Firefighter I
12–25
Water Shuttles
• According to NFPA® 1901, water
tenders on level ground should be
capable of dumping/filling at rates of at
least 1,000 gpm (4 000 L/min)
(Continued)
Firefighter I
12–26
Water Shuttles
• To fill water tenders quickly, use best fill
site, large hoselines, multiple hoselines
• Multiple portable pumps may be
necessary
Firefighter I
12–27
Relay Pumping
• Can be used in situations where water
source is close enough to fire scene to
render water shuttles unnecessary
• Factors to consider
– Water supply must be capable of
maintaining desired volume of water
– Relay must be established quickly
(Continued)
Firefighter I
12–28
Relay Pumping
• Determining number of pumpers
needed and distance between them
– Several factors to take into account
– Apparatus with greatest pumping capacity
should be at water source
(Continued)
Firefighter I
12–29
Relay Pumping
• Determining number of pumpers
needed and distance between them
– Large-diameter hose or multiple hoselines
increase distance, volume a relay can
supply
– Water supply officer should consider all
factors and determine correct distance
Firefighter I
12–30
Summary
• Because water is still the primary fire
extinguishing agent used by firefighters
in North America, and because fires
often occur considerable distances from
major water sources, fire departments
must develop ways to transport
available water from its source to where
it is needed.
(Continued)
Firefighter I
12–31
Summary
• Firefighters must know what water
supply systems have been developed
and what their responsibilities are when
these systems are used.
Firefighter I
12–32
Review Questions
1. What is the difference between drybarrel and wet-barrel hydrants?
2. How are fire hydrants marked?
3. What factors affect hydrant location
and spacing?
(Continued)
Firefighter I
12–33
Review Questions
4. List alternative water supplies.
5. What are three key components of a
water shuttle operation?
Firefighter I
12–34