As climate shifts bring more extreme weather and high-water risks, new tests by the ADAC in Germany expose an often-overlooked danger: what happens when a car plunges into water? Are electric car drivers at a higher risk than those in a combustion-engined vehicle?
In the experiment, the German organization submerged two cars: a conventional Seat Exeo ST with a diesel engine and an electric Citroën ë-C4. The aim was to observe how fast vehicles sink, and what happens to their electronics and high-voltage systems. The goal was to identify whether drivers stand a real chance of escaping.
Fatal misunderstanding
The verdict is sobering: time is your enemy. In the ADAC’s test, the Citroën sank in about three minutes, the Seat took just a minute longer. Meanwhile, the controlled test showed that waiting for a car to fill with water, in the hope of opening the doors, is often a fatal misunderstanding.
By the time the interior is fully submerged and pressure equalizes, the driver could be underwater for 90 seconds or more. Many simply do not survive that time window, especially in cold, murky water.
Meanwhile, the myth that electric cars are more hazardous in water has been debunked. The Citroën’s high-voltage system showed no faults underwater. It didn’t short-circuit and remained in stable conditions.
Also, the 12V system that powers the windows kept working for approximately ten minutes in both test cars. The opening of the doors remained functional as well. The fear of immediately blocked windows is not justified. As such, passengers have the opportunity to provide themselves with an escape route.
Danger of laminated windows
Yet, the situation gets more hazardous when the windows don’t open. The ADAC managed to break the safety glass from the side windows in the Citroën (advise: aim for the corners as the center point of the window is resistant), but failed to do so in the case of the Seat, which had laminated ones.
Modern cars increasingly use laminated side windows — once reserved for windscreens — for soundproofing and theft protection. Laminated glass is constructed from multiple glass layers with a plastic film in between. This makes it stronger than tempered safety glass, which shatters into small pieces. Instead, laminated glass stays intact, even after a hard impact. This is great for rollovers — preventing passengers from being ejected — but deadly in the water.
Compounding the problem is that most drivers have no idea what type of glass their car has. In Europe, laminated glass is marked with codes on the corner of the window — look for commercial names like ‘Lamisafe’ or Roman numerals like II near the E-mark. Still, few owners check.
1% of incidents
The ADAC test confirmed this: despite repeated strikes with a rescue hammer and a spring-loaded punch, the Seat’s laminated side windows could not be shattered.
For cars with this type of glazing, the only realistic option might be the rear window, which is still usually made of breakable safety glass. However, as both tests showed, cars often sink nose-first, making the boot difficult to reach, especially if luggage blocks the way.
Still, ADAC urges drivers to keep a rescue hammer and seatbelt cutter within reach. In Belgium, the incident rate for water accidents involving cars remains low, aligning with the global level of 1%.
According to the traffic safety institute Vias, these incidents include cars ending up in smaller canals along the road, where the car is (not necessarily) submerged. In the Netherlands, the rate is higher. Nearly 800 cars end up in the water each year, resulting in an average of 50 lives lost.
