During the summer months, many families spend time relaxing and enjoying extra days in and around the water. Sometimes that means taking the time to visit the family lake house and take out on the family boat in a lake or river area. But for some, a dip in the lake can put them at risk for deadly consequences. Unfortunately, there is a silent killer associated with swimming around boats in freshwater, and it’s something that all boaters and their families and anyone who chooses to swim in freshwater should be aware of this summer.
Electric Shock Drowning (ESD) is a term used to describe any death that occurs in the water that is caused by an electrical current. Any time there is a power source with alternating current (AC) that is utilized near the water, such as on a boat and dock, there is a risk of this type of danger. We’ll explain in more detail what ESD is and how it can be prevented.
What is ESD?
If a person appears to suddenly drown in a freshwater environment while swimming near a dock or marina, it is possible that he or she has been a victim of ESD. ESD occurs when there is alternating current (AC) traveling through the water from a power source on a boat to its ground source on land, such as between a boat and a transformer at the marina. The current can paralyze someone under the water and cause him or her to drown. It’s scary and often undetectable without equipment.
Why is Fresh Water More Dangerous?
Saltwater is actually 50-1,000 times more conductive than freshwater, with the conductivity of a human body falling somewhere in between the two. In saltwater, the human body slows electricity down, so most currents will go around a body to get to the ground unless the swimmer grabs ahold of something like a boat propeller or metal swim ladder. In freshwater, the current can get “stuck” in the water on its return to a source, such as a transformer on land, and will generate voltage gradients that will take a shortcut through the body to get to the ground. Alternating current going through the body will disrupt internal electrical signals to nerves and muscles, therefore causing paralysis. Even small amounts of this type of current can kill a swimmer by rendering him unable to use his muscles, resulting in drowning.
How does Electricity Get in the Water?
The alternating current finds its way into the water primarily through an electrical fault in the power lines that run from a boat to a power source at a marina. If there is current escaping through the water and trying to find its way back to the source, this could cause a dangerous electrical field under the water surrounding the boat. The boat’s underwater metals will become energized, and electricity will radiate into the water, potentially harming any swimmers nearby.
How to Prevent ESD
- The best way to prevent a death by ESD is to never swim near a dock or marina where there are boats that are receiving power.
- Boaters should regularly have their boats checked to ensure that all power systems are running properly and not leaking current.
- Boaters should check with marinas to ensure that they are also inspected and that their power sources are not leaking.
- Marinas should also be equipped with ground fault detectors to ensure that as the electricity running into boats is not leaking into surrounding water.
- Boaters should also invest in an isolation transformer that can completely isolate the AC shore power from the system on the boat to better protect the integrity of the power system.
Victims of ESD are typically children, but these types of drownings are largely preventable with responsible boating and restricting swimming in marinas where boats are plugged into a power supply.
If you feel that you or someone in your family has been a victim of someone else’s negligence on the water, it’s important to contact an experienced personal injury attorney. Your attorney may be able to help you recover financially from your losses.
References:
Electric Shock Drowning Prevention Association. (n.d.). Retrieved from http://electricshockdrowning.org/
Electric Shock Drowning (ESD) Explained – BoatUS. (n.d.). Retrieved from https://boatus.com/seaworthy/magazine/2013/july/electric-shock-drowning-explained.asp
