Just before the flood:
If a flood is imminent and the home’s sewer already has a backflow preventer installed, there aren’t any further actions to be taken. Should the backflow preventer be a manual valve, make sure that it is closed. For a tank without a backflow preventer, it may be a good idea to pump the tank so that it is free of sewage. However, it needs to be anchored correctly to stop it from floating as waters rise. When a tank is pumped, some solids may remain and can mix with any floodwater that enters the tank. Lower level drains in the building may need to be blocked so that backup isn’t able to enter.
When a flood is occurring:
During a flood, the soil treatment system may not be flooded, but it could still be very soggy if heavy rainfall took place. In that case, it is recommended to cut down on water use as much as possible. Any futher water that enters the system may lead to improperly treated sewage surfacing or a sewage backup entering the house.
Should a system be completely flooded, it shouldn’t be used. All electric devices such as pumps and alarms need to be turned off. Water softeners should be deactivated as well. A septic system will not be able to properly function when the ground above it is flooded.
After the flood passes:
The soil should have sufficiently dried before the septic system is used again. This ensures that the sewage will be absorbed and won’t back up. However, the soil may take several weeks before it is dry again. Users should reduce their water use until it is confirmed that the entire system is dry. A system that has been flooded may be damaged, but there are ways to minimize this and help it recover.
All electrical connections should be inspected for damage before the electricity is turned back on. The tank and treatment unit will need to be pumped immediately after the flood has passed and before the septic system is used again. The septic system should be inspected for any debris that could have entered the tank in order to avoid any further damage.
If a system was heavily damaged:
Severe flooding can lead to a septic system being partially or completely destroyed as components wash away. If it becomes necessary to construct new system components, the area should be inspected for the presence of debris. These should be removed from the area to protect the system, as they can have a significant impact on its operational integrity.