Septic Systems

A septic system is usually located on the same property where wastewater is generated. If maintained and operated properly, it is a highly efficient, self-contained underground treatment system. It is recommended to keep a septic system pumped appropriately and in good working order at all times because a well-maintained septic system is better able to withstand the stresses of heavy rains or flooding. A septic system must be regularly inspected and maintained to function properly and prevent contamination of nearby wells, groundwater, and streams. Heavy rains and floods can halt a system’s ability to treat wastewater, and possibly flood nearby drinking water wells. In a water-related emergency, septic systems may flood or malfunction. The following signs may indicate that a septic system has malfunctioned:

• Drains in the home flow slowly.
• Toilets drain slowly or sound strange when flushed.
• Water backs up into floor drains in the basement.

The United States Environmental Protection Agency (EPA) has prepared information on Managing Septic Systems to Prevent Contamination of Drinking Water (PDF, 132.49 KB, 5 pages).

Before an Emergency

Flooding or other damage to a private septic system increases the possibility of contaminating aquifers or nearby drinking water sources with a back-up of sewage. There are steps that homeowners can take to prepare their septic system before a water-related emergency:

• Seal all possible points of excess flow to the system. If possible, seal the manhole and inspection ports to keep excess water out of the septic tank.
• Make sure all septic tanks are full of liquid.
• If your septic system is dependent on electricity:
  • Turn off the pump at the circuit box before the area floods. If the pump is located in the lift station of a mound system, turn off the electricity. If possible, remove the pump from the tank to prevent sediment damage.
  • Waterproof all electrical connections to avoid electrical shock or damage to wiring, pumps, and the electrical system.

During an Emergency

During a major rain or storm, homeowners should eliminate all non-essential water use and flush toilets as little as possible. If the drainfield becomes covered with water, homeowners should not use the system at all and avoid contact with any standing water that may contain sewage. During a flood or other water-related emergency, remember the following:

• Discontinue use of the septic system.
• Do not drink water from nearby wells, they may become contaminated.
• Do not bathe or swim in floodwater.

After an Emergency

After a major storm or flood has occurred and floodwaters have receded, homeowners should remember that the soil around a drainfield will be saturated with water. There are things homeowners should remember:

• Avoid contact with any electrical devices that are part of the system until they are dry and clean.
• Do not drink the water from nearby wells until they are tested by the county health department using a drinking water test kit.
• Do not have the septic tank pumped. Doing so may cause the tank to float out of the ground, damaging the inlet and outlet pipes.
• Discard any items damaged by contaminated water that cannot be steam cleaned or adequately disinfected.
• Do not pump water out of a basement too quickly. Exterior water pressure could collapse the walls.
• If sewage has backed up into the basement, clean the area and disinfect the floor with a chlorine solution of one-half cup of chlorine bleach to one gallon of water.

If at all possible, homeowners should avoid using the septic system, allowing time for the water to recede and the soil around the drainfield to dry out. Several ways to reduce water use include the following:

• Re-route water from roof gutters away from the drainfield area.
• Do not use the dishwasher or garbage disposal.
• Do not use the washing machine.
• Reduce the number of showers taken.

After the emergency, have the septic system professionally inspected and serviced if damage is suspected.

Both the National Environmental Services Center (NESC) and the Environmental Protection Agency (EPA) have prepared septic system maintenance guides for homeowners. For complete information on septic systems and water-related emergencies, the following information is available:

• First Aid for a Flooded Septic System (PDF, 195.37 KB, 4 pages) (National Environmental Services Center)
• Septic Systems – What to do after a Flood (EPA)
• Flooded Private Sewage Systems (National Ag Safety Database)