Sewage systems and flooding: safety, sanitation, and clean-up
Flooding of a private sewage system can be dangerous for homeowners. Sewage can back up into the home and may contaminate drinking water.
Remember: A well can become contaminated during a flood. Therefore, do not drink the water until it has been tested.
What should I do during a flood?
What should I do after a flood?
Once flood waters have receded, homeowners should remember:
Have your septic system (and the lift station if applicable) pumped by a professional as soon as possible after the flood, once the soil is no longer saturated or flooded.
Wait til the soil is no longer saturated before you have it pumped. Pumping out a tank that is in saturated soil can cause it to “pop out” of the ground, which can damage the inlet and outlet pipes. Systems that were installed recently can “pop out” of the ground because the soil has not had enough time to settle and compact.
Do not compact soil over the soil absorption field by driving or operating equipment over the area. Saturated soil is especially susceptible to compaction, which can reduce the soil absorption field’s ability to treat waste water and can lead to system failure.
Ensure the septic tank’s manhole cover is secure and that inspection ports have not been blocked or damaged.
Examine the vegetation over your septic tank and soil absorption field. Repair erosion damage and sod and/or reseed as necessary to provide a vegetative cover.
What should I do in the house?
If the septic system backs up into the house, check the tank first for outlet blockage. Flooding of the septic tank will have lifted the floating crust of fats and grease in the septic tank. Some of this scum could have plugged the outlet tree.
Clean up any floodwater in the house. Avoid dumping water into the sink or toilet until the flood water has receded. Flood waters from the house that are passed through or pumped through the septic tank will cause higher flows through the system. This can cause solids to transfer from the septic tank to the drain field and will cause clogging.
What about my flooded well?
A well can be contaminated during a flood. Be sure to test your well water before drinking. Contact the North Bay Parry Sound District Health Unit for information on testing your water and decontaminating your well after a flood or check out these tips from the Haliburton Kawartha Pine Ridge District Health Unit on their website.
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