How Does Flooding Affect Underground Oil Tanks?

When the ground around an underground oil tank becomes waterlogged, the soil loses its grip. The tank can literally float upward, even if it is full. That movement strains the pipes and fittings connected to the tank, which can crack or pull apart. You might not see the damage from the surface.

Water can also enter the tank through a loose fill cap or a damaged vent. Once water gets inside, it settles at the bottom. That water can cause rust and corrosion over time, and it can also feed bacteria that turn the oil into a sludge. The heating system may then run poorly or stop working.

Turn off the heating system and the oil supply valve if you know where it is. Keep people and pets away from the tank area. Do not attempt to pump the tank or remove water yourself, as that can create sparks or spread oil.

Contact your local fire department or environmental agency if you see oil on the ground or water. They can tell you if the situation is an emergency. Then call a qualified oil tank professional to inspect the tank and the lines before you use the system again.

If you live in an area prone to flooding, consider having a professional anchor your tank or install a watertight fill cap. Keeping the area around the tank clear of debris helps water drain away. You can also note the location of the shutoff valve and keep it accessible.

After any flood, even a minor one, schedule an inspection before the next heating season. Regular checks can catch small problems early. Keep your shutoff valve location written down. Local water damage pros can handle cleanup if a leak occurs.

• Anchor the tank to resist flotation
• Install a watertight fill cap
• Keep the tank area clear of debris
• Know your shutoff valve location
• Schedule an inspection after any flood