Carl Brahe
Fire is probably not the first thing you think of as the result of flooding, especially not months later. The 2013 Boardwalk fire in Atlantic City, NJ was caused by corrosion of wiring and wiring connections that were flooded by Hurricane Sandy almost 11 months earlier. Wiring connections immersed in salt water corroded connections causing excess heat that ignited building materials. Romex type wiring usually used in this kind of application contains a paper that separates the individual wiring in the sheath. Water wicked up the paper causing the wiring cover to degrade allowing wires to touch.
The rule of thumb for electrical devices that have been submerged is replace them. The fire hazard from soaked electrical devices is not worth trying to save them. Outlets, switches and breaker boxes are the obvious electric devices that need replacement. Appliances, heaters, furnaces, AC units and anything else that contains electric motors, switches or wiring are included. Flood waters contain mud that can deposit in these devices causing overheating and/or mechanical failure. Flood waters can contain many toxic substance that may include: fuels, solvents, cleaning chemicals, industrial chemicals, sewage, fertilizers, pesticides, herbicides and other toxic compounds. If these are heated they may off gas releasing carcinogens, allergens or poisonous fumes.
The more immediate electrical hazard after a flood is shock or fires caused by electrical sparks and gas or fuel leaks. When you approach your home or business after a flood notice the main electrical service. It is either above ground with the wires coming from a pole to a mast extended above the roof or underground with a conduit rising from the ground to the breaker box, shutoff or entry point through the exterior wall. Underground electrical service is required to be in conduit with a slip joint above ground level that can allow water to enter. The wiring used in this conduit is required to be weather proof, but if the slip joint is under water, or if the overhead wire is down, or the underground conduit is exposed by erosion, call your power company before entering. If the main shut off is accessible without standing in water and it has not been submerged at any time turn it off. The main shut off is usually the top two breakers in a main breaker box in residential and is a separate box with an “ON/OFF” lever on the side next to the breaker box(es) . Shutoff the gas supply to the building by turning the valve usually located just before the gas meter.
For safety the electric meter should be removed to prevent any possibility of the wiring being energized by generator use in neighboring home or businesses. The wiring from neighboring houses or other buildings is connected to your wiring through the main power supply lines. When the electricity is off with no possibility of being energized from generators in neighboring buildings that have been plugged into the other buildings electrical system it may be safe to enter from an electrical standpoint. Other dangers when moving through flooded rooms include: drowning, open sump pits and other hidden dangers may exist, cuts and abrasions from underwater objects, chemical burns, poisoning and irritations to skin, sinuses or eyes. Avoid contact with flood waters when possible. Wear protective clothing and mask when you have no choice.
Document electrical components and devices that have been damaged. Even if you don’t have flood insurance this documentation may be valuable for use with FEMA or other aid agencies. Contractors may find it useful to see the full extent of the damage at its worst.
Underwriter’s Laboratory recommends replacing:
• Circuit breakers and fuses
• All electrical wiring systems
• Light switches, thermostats, outlets, light fixtures, electric heaters and ceiling fans
• Furnace burner and blower motors, and ignition transformers, elements and relays for furnaces and hot-water tanks
• Hot-water tanks
• Washing machines, dryers, furnaces, heat pumps, freezers, refrigerators, dehumidifiers, vacuums, power tools, exercise equipment and similar appliances
• Electronic equipment, including computers and home entertainment systems
Electricity can travel through many pathways to electrocute those who touch these mediums. Electricity can travel through metal pathways like wiring, furnace ductwork, plumbing or gas lines. It can also travel through water and water soaked ground or carpet. The most important thing when it comes to electricity and flooding is make sure it is turned off until you know it’s safe to turn it on.
Other Resources
Home Energy Magazine – Rehab After the Flood
The United States Fire Administration Office of Fire Management Programs – Flood
Flood Recovery Checklists from NDSU Extension Service
- First Things First
- Safety
- General Cleanup
- Cleaning Carpet and Floors
- Cleaning Household Items
- Cleaning Valuable Items
- Electrical Cleanup
- Flooded Foods
- Make Sure Water is Safe
- Dealing With Stress After a Disaster
- Replacing Your Important Papers
- Financial Recovery
- Gardens and Landscapes