Prepare home fuel storage tanks for possible flooding

As snow melts, many Minnesota residents brace for possible flooding. To avoid messy and costly cleanup, prepare your fuel oil, gasoline, and other petroleum tanks for flooding.
Prepare aboveground fuel tanks
The best way to prepare aboveground fuel storage tanks for a flood is to have them emptied. Your bulk fuel distributor can do this. If that’s not possible or practical, the tanks should be secured to concrete anchors or deadmen in the ground so they cannot tip or float away. Valves to hoses or dispensers should be securely closed.
Prepare underground fuel tanks
Because water is heavier than fuel, floodwater can enter underground tanks, pushing the fuel out. Underground tanks should be topped off, and their vents and fill openings sealed so the tanks are watertight. Another option is to remove the contents of the tanks and fill them with water because an empty or partially full tank can become buoyant and pop out of the ground.
More information for farmers and businesses with underground storage tanks is available on the Floods: Minimizing pollution and health risks webpage
Prepare indoor fuel tanks
If enough floodwater enters a basement, an unsecured fuel oil tank may become unstable, tip over, and/or float. If a tank’s vent, fill pipe, or other openings are not water tight, floodwater will enter the tank and displace the fuel into the home or office.
In addition to creating possible health, fire, and environmental hazards, the fuel will be absorbed by any porous material (wood, cinder block, carpet, and drywall) it comes in contact with. Once that happens, fuel vapors and strong odors may persist in the building indefinitely.
These steps will help prevent spilling or leaking of fuel from an indoor tank in the event of a flood:
- If floodwater is expected to be high enough in your home to cause your tank to tip over or float, have a bulk fuel distributor remove the fuel from the tank and plug its vent and fill pipes. This will prevent or reduce leakage of fuel into your house if floodwater tips the tank over or enters it through an opening.
- Your fuel storage tank may float like a bobber if your basement becomes flooded. Strap the tank down so it will be kept in an upright position if floodwater causes it to float. Anything used to secure the tank must be able to withstand the buoyant forces. The fill and vent must be plugged to prevent water from entering the tank and displacing the fuel.
- If floodwater gets into your house but does not come into contact with the tank, monitor the situation to ensure that the tank’s supports are secure and its stability is not undermined by the water.
- If your fuel storage tank is no longer in service, remove the unused equipment, including all piping, and seal the vent and fill openings on the building so that no one can ever fill your basement with fuel by mistake.
If your tank has leaked
If your tanks become damaged or it has leaked, call the Minnesota Duty Officer at 651-649-5451 or 800-422-0798. The MPCA can help a tank owner arrange for cleanup, and the Minnesota Department of Commerce may reimburse most of the costs of a fuel cleanup.
For more information and assistance
If you have questions, call toll-free at 800-657-3864 to contact the MPCA office in Detroit Lakes, Marshall, Willmar, St. Paul, Rochester, Brainerd or Duluth.
More advice on what to do before and after flooding to minimize risks to health and damage to property and the environment is on the Floods: Minimizing pollution and health risks webpage.
