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Swiftwater
Rescue II
Lesson 1:
Characteristics
of Moving
Water
Powerful
Relentless
Predictable
Site reference
Upstream
River Right
River Center
River Left
Downstream
References
remain the
same even
when the
perspective
is reversed
Water dynamics
two general categories of
moving water...

Laminar flow
Layers of moving water

Helical flow
Circular flow of water along the
bank, forcing water to midstream
Laminar flow
Fastest
Fast
Slow
Slowest
Straight Section
Fastest
Fast
Slow
Slowest
Outside Bend
Helical & Laminar flow
Laminar Flow
Helical Flow
Water dynamics

Water is fastest…
at the surface and midstream

Water slows down…
along banks and bottom

Water is faster…
at the outside of bends and slower
on the inside of bends

Water slows down and deepens…
in front of dams and other
obstructions
Separating fact from
fiction...
Lesson 2:
The Human
Body in Water
Fact...
In still water, the weight of
a body will cause it to
settle in a near vertical
drop to the bottom
In moving water...
Faster
Slower
Since current moves faster at the surface and
slower along the bottom, a body will drop through
the layers of laminar flow as it is transported
downstream and deposited on the bottom.
The distance downstream depends
on the velocity of the laminar flow
Fiction...
A body will be swept
downstream in any current
Fact...
Adult drowning victims
submerged in moving water
tend to resist lateral movement
in currents less than 1.5 mph
Fact...
When a drowning occurs in an area
of white water, the body will probably
continue to move with the current until
it becomes lodged or the current slows
and allows the body to settle
Body type and clothing...

Lighter, less resistant body types will be more
easily transported

Amount of body fat and air trapped in clothing will
contribute to buoyancy

Depending on body type and clothing, some
infants and small children may never sink

Clothing may increase the potential to snag and
hold a victim stationary in a strong current

Clothing usually adds little to the
weight of the victim under water but
may affect buoyancy and drag.
The phenomenon of
body refloat...
Once decomposition begins the process
of gas formation in the victim’s body,
buoyancy can change drastically
Fact...
Unless the victim is snagged or
wedged, gas formation may eventually
allow the body to raise to the surface
where it could be transported
downstream by the faster moving
surface current
Physiology of body
refloat

Time

Temperature

Depth

Victim
considerations...
Victim considerations

Body type

Diet

Clothing

Trauma
(pre and post immersion)
Not all bodies will refloat!
Under certain conditions, a body may
remain snagged, trapped in a strainer,
held in a water hydraulic or become
covered with silt and stay undetected
for years
Lesson 3:
The search of moving
water is at best difficult
and challenging. Such
activities present great
obstacles for swiftwater
rescue teams and often
expose searchers to the
threat of personal injury
or death.
Safety
Considerations
Safe and effective search
operations near moving
water depend on proper...

Preparation

Training

Equipment.
Hazards include...

Water hydraulics

Strainers
(barb wire, tree limbs, log jams, debris)

Slippery, unsure footing

Topography
(access, cliff faces, drop-offs)

Manmade obstructions
(dams, bridges, debris)

Cold water
Associated risks include...

Drowning

Entrapment

Hypothermia

Blunt trauma

Cuts and lacerations
The safety of
all personnel must
always be the highest
priority!
Always consider
the Risk/Benefit
Analysis of every
operation!
The role of search teams is
to facilitate clue location...

Only personnel appropriately trained
in swiftwater rescue should enter the
water to recover any object

Have preplan in place for appropriate
action prior to object location
There is safety in numbers

Never search alone; search teams should
consist of three or more person/teams

Searchers should have knowledge of
self-rescue and victim-rescue techniques

Exercise caution, continually re-evaluate
the Risk/Benefit Analysis and be prepared
to assist teammates in an emergency

Be properly equipped
Shored-based
Personal Protective
Equipment
 PFD
with whistle & knife
 Environmental
protection
 Gloves
and boots
 Throwline
 Helmet.
bags
Water-based PPE for
swiftwater rescue







Thermal protection
PFD
with knife & whistle
Helmet
Swiftwater rescue
board
Hand & foot
protection
Fins/mask/snorkel
Throwline bags
Swiftwater team equipment

Throwline bags

Line gun

Tag line buoy

Multi-chambered, inflatable boat

Rope rescue equipment and
hardware

Communication equipment

Additional PFDs & helmets

Other specialized
equipment
Search equipment
includes...

Probe device

Binoculars

Polarized sunglasses

Flagging & permanent marker

Rope and climbing equipment

GPS.
Lesson 4:
Scene
Evaluation
The critical stage of search
operations
Scene evaluation...
Begins with the initial call
for assistance but continues
throughout the entire
operational phase of
the search
Start the process early
A systematic and objective size-up
or assessment of the incident is
particularly crucial at the onset of
the search
A good scene evaluation
identifies...

Incident type

Location and access

Time of occurrence

Environmental conditions

Resource needs

Witness identification

Ability to control water volume
The primary operational
objective is to establish a
“Last Seen Point”
Determining the
Last Seen Point (LSP)...

Physical evidence

Witness interviews

Reference objects vs.
reference points

Knowledge &
experience as SWR
scene evaluator
Witness interview
The witness interview is perhaps
the most critical component of a
scene evaluation and is essential
for determining the LSP
Witness
interview

Control and organize
witnesses

Separate and interview
individually

Question thoroughly and
methodically

Don’t ask leading questions

Go slow, stop & listen

Qualify witnesses by order
of importance.
Establish a subject
profile listing

Physical description

Clothing type and colors

Shoe pattern

Equipment or personal items

Intended plans

Experience level, etc.
“Last Known Activity”
In cases involving an unwitnessed
or poorly witnessed drowning,
the last known activity may
provide the only clue to the
location of the body
And most important
Write it down!

Compile all statements, information and
documented clues in a centralized
collection point

Use this material to develop a scene
sketch for future reference
Components of scene sketch:

LSP- Last Seen Point

Location of physical evidence

Location of witnesses

Permanent landmarks used to triangulate

Access points (e.g. dock, boat ramp)

Current speed
Summary
Developing a thorough scene evaluation
and determining an accurate Last Seen
Point may be the most important tasks
you will perform during the initial stage
of any search operation.
Lesson 5:
Establishing
Operational
Objectives
Photo by Lucas Gilman
Search
planning
Is largely driven by information
gathered during scene evaluation
A successful search operation
depends on an accurate
assessment of the situation
Rescue vs. recovery
search operations
The choice of tactics may vary
during a search, especially in
the initial phase
The operational mode will help
drive the tactical considerations
and assist in Risk/Benefit
Analysis
Initial search objectives…

Determine the LSP

Evaluate the current’s capacity to
move objects downstream

Estimate size of search area

Identify resource needs

Identify potential hazards for rescuers

Define/prioritize high probability areas
Ongoing search objectives…

Segment search area as needed

Determine effective search
methods necessary to
thoroughly cover areas

Assign resources according to
skill level

Perform ongoing evaluation
of process
The search should always begin
with an investigation of the
Last Seen Point
Never assume that the body of a
missing victim has floated away until
the LSP has been thoroughly
searched
Review of drowning
characteristics...

Bodies tend to resist current
less than 1.5 mph

The body will generally drop to the
bottom

Current on the surface is greater than
the bottom current

Bodies of adult drowning victims
generally weigh between 7 and 16
pounds in water
Identify all high probability areas and
concentrate search first in sections
where water slows down or where
strainers and other objects may
snag victim
High
probability
areas
include

LSP

Strainers

Boulder sieves

Low head dams

Bridge abutments

Hydraulics
Eddies
Holes

Where water slows down.
Shoreline
Sand bars
River bends
Summary
Understanding water dynamics, body
characteristics in water, safety concerns
and resource capabilities allows rescuers
to determine areas of high probability and
establish search priorities.
Lesson 6:
Search
Tactics
Search tactics may vary
depending on
circumstances of the event

Witnessed incident vs. unwitnessed
vs. general missing persons report

Rescue vs. recovery

Risk vs. benefit.
Initial actions in
rescue mode...
Establish an initial
containment area based on
current speed and time of
incident
Contain and control...

Assign hasty teams to search from
LSP downstream

Post containment teams
downstream at bridges and other
vantage points

Assign additional teams to high
probability areas

Search banks for possible exit
points downstream
Tactical considerations for
every rescue team...

Are site conditions too dangerous
to put anyone in the water?

Are there sufficient resources
available to cover the search area
quickly and effectively?

Is it possible for searchers to
effectively cover the area?

Will more manpower allow greater
coverage in a shorter period of
time?
Ongoing concerns...

As additional resources arrive, stagger
teams throughout search area

Assign teams based on experience level
and search priorities

Establish land-based searchers to assist
swiftwater teams with object retrieval

If available, assign dog teams to work LSP
A slow, careful scan of the
river is necessary. Study any
irregularities in color, shade or
shape of the surface
Study every section from at
least two vantage points
Probe search...

The ideal probe is a
7-foot, 3/4”
aluminum pole

Improvise as
needed to meet the
situation at hand

Tap and “feel” the
bottom with the
pole from the
downstream side
Exercise extreme
caution when working
along the shore!
Search shorelines
including vegetation
along banks.
Search sharp bends or curves in
the river and areas of natural
entanglement or entrapment
using a probe pole
Line searching may be effective where
water is shallow and predictable
Whenever possible,
post an observer as an
overseer and additional
safety personnel
downstream for the inwater search teams
Suggested team assignments
LSP
Team 1
A
Team 2
DP 2...
DP 1
Team 3
Current
Team 4
Team 5
B
Team 7
In-water Teams
Team 6
Team 8
Swiftwater teams work down from LSP
and concentrate on areas of high
probability
Team 9
C
Team 10
Extended search
operations...

Hasty search is followed up by a
controlled, methodical search of the
banks and river hydraulics

Rule out “rest of world”

Identify resource needs

Ongoing scene evaluation

Consider trained SAR dogs.
“Don’t just look for a body,
search for clues!”

Tracks

Disturbances in vegetation

Articles of clothing

Equipment
Perceptions & expectations...

The body may blend into
the color & textures of the
surrounding environment

Flesh tones tend to blend
with white water

Skin color may appear
very white to luminous

Floating debris, strainers and overhanging
branches can easily hide or camouflage a
body in swiftwater

Conditions often require a slow and
methodical search of the area

While it is necessary to have a good
clothing and physical description of the
victim, be aware that clothing and jewelry
are often stripped away in the forces of
moving water and the body
may be nude
Once the body is located

Mark it…
identify location with flagging,
GPS, etc.

Secure it...
with rope if safe to do so

Stay with it...
remain with victim and monitor until
recovery team arrives
If there are suspicious
circumstances surrounding
the incident, take special
precautions so as not to
destroy evidence
Photograph and record body
position, obvious trauma, etc.
Bag hands and feet
Considerations for
family & media...

Have a preplan for action in place
before the victim is found

Assign a team member or “trained”
victim’s advocate to the family

Assign a team member or PIO as
representative

Quietly notify team and
command staff
Trauma often
associated with moving
water fatalities...

Whenever possible, have the family
escorted from the scene before the
victim is removed from the water

Encourage the family to wait until the
body is at the morgue or hospital
before viewing their loved one

Consider the need for CISD
If victim is not located...
Gas formation may occur days, weeks or
months later and body refloat could move
the victim outside the initial containment
area. As a result, continual monitoring of
the area over an extended period may be
necessary.