February 10, 2021 Self-Rescue from Submerged Vehicles

Each year, there are thousands of submerged vehicle incidents resulting in numerous deaths.  In the United States alone, there are approximately 1,200 – 1,500 incidents annually resulting in 400 – 600 deaths.

Steps To Reduce Submerged Vehicle Deaths

Public service announcements (PSAs) and campaigns should be increased in an effort to educate the public about the risks of driving through flooded roadways; driving in close proximity to bodies of water during snow, rain, or other slippery conditions; or driving over frozen bodies of water.  The following information should be included within these PSAs:

• It only takes approximately 6” of water to sweep a person off his/her feet. And, it only takes 1’ to 2’ of water to float a vehicle off its wheels.  Drivers need to heed warnings about high water on the highway and should never attempt to cross flooded roadways.
• No ice should ever be considered as safe ice! But, if you are going to risk driving over frozen bodies of water, at least 8”- 12” of new, clear, hard ice is required to drive a small vehicle over the ice; and 12” – 15” of new, clear, hard ice is required to drive a full-sized pickup truck over the ice.
• Wearing seat belts will increase your chances of surviving a crash into the water.

Municipalities can take steps to mitigate these incidents and should install appropriate guardrails along the roadways that are adjacent to bodies of water.  Regardless, drivers should prepare for submerged vehicle incidents and drivers and occupants should discuss the emergency procedures for survival in the event of a submerged vehicle incident.

What Happens To A Vehicle After Landing In Water?

If a vehicle leaves the road and lands in deep water, most passenger vehicles will float on the surface for a short period of time (30 seconds to several minutes).  During this time, the vehicle will begin to fill with water as it seeps in through the floor boards.  And, as the water fills the vehicle, the vehicle will continue to sink deeper into the water.  If the water is deeper than the height of the vehicle, it will submerge and disappear beneath the surface.

Factors that can effect the float time of the vehicle include closed and intact windows and the weather seals around the windows and doors.  Other factors include the design, body style, construction quality and the condition and age of the vehicle.  Because the location of the motor in the front of the vehicle, the vehicle will immediately assume an angled nose down position in the water.  A vehicle with the windows and/or doors open will fill more rapidly and will submerge faster than the same vehicle with its windows and/or doors closed.  The faster the water enters the interior of the vehicle, the faster it loses its buoyancy and the quicker it descends.  A vehicle that has all the windows and doors closed and intact will initially descend slowly, but as the water continues to seep in through the floorboards, the vehicle will rapidly lose buoyancy and the speed of descent will increase.

Surviving A Submerged Vehicle Incident

There is a very short window of time for self-rescue.  Therefore, the decision to escape the vehicle must be made as soon as the vehicle leaves the roadway and enters the water!  If the occupants delay their escape from the vehicle, once the water outside the vehicle reaches the windows, it may be impossible to escape the vehicle until the water pressure has equalized inside the vehicle.  Unfortunately, by that time, it may be too late to escape.  And, if the depth of the water is greater than 14’, there is chance that as the vehicle descends, it may end up on its roof, rather than right side up on its wheels.  Being upside down in a dark environment with water rushing in will disorient the occupants of the vehicle.

Because of the angled nose-down position of the vehicle in the water, and the pressure exerted by the water against the doors, it may be extremely difficult, or impossible, to open the driver’s or passenger car doors in order to effect an escape.  And, if the vehicle sustained structural damage during the incident, that will also effect the ability to open the doors.  Therefore, the only avenue of escape may be through the car door windows.

Most, if not all, late model vehicles are equipped with electric window switches and motors designed to raise and lower the windows.  Once the vehicle enters the water, although the electric power may stay on for a while, once the switches and motors get soaked, they will generally short out and the windows will no longer be able to be lowered.  Therefore, in order to escape the vehicle before it submerges, the occupants must lower or break the side door windows.  If the windows are made of tempered glass, the glass will easily shatter using a commercial escape tool or a spring-loaded window punch.[1]  However, these tools do not work on laminated glass.  And, most late-model vehicles are now being manufactured with laminated, instead of tempered glass.

Lifesaving Resources advocates the following emergency procedures to escape your vehicle.

Seatbelts (off or cut)

Windows (open or break)

Children (removed)

GO! (get out)

These emergency procedures should be rehearsed before the emergency occurs.  As an example, the driver should practice finding the location of the door latch and window switch by touching his/her knee or hip with his near hand and then move the hand towards the latch or switch.  If the vehicle has tempered glass in the door windows, a commercial rescue tool or a spring-loaded window punch should be immediately available for use to punch out the window.  And, if there are multiple occupants, once an escape route has been established (through a door or window), each occupant should hold hands to form a human chain and everyone should exit from the same route.

There is no doubt that when a vehicle leaves the roadway and plunges into the water, this would be an extremely frightening experience, especially during the winter months with cold water posing additional risks and hazards to the occupants.  But, by rehearsing the emergency escape and survival procedures, occupants can rapidly self-extricate themselves from this situation before the vehicle sinks.

[1] Many of the commercial tools have an integrated seat-belt cutter that provides the occupants with the ability to slice the seat belt should the release mechanism fail.