RAYMOND, Miss. -- Problems with private septic systems can be expensive, messy and hazardous to Mississippi’s drinking water. But homeowners can take some proactive steps to keep their systems functioning properly.

“The majority of our drinking water in Mississippi comes from groundwater sources,” said Jason R. Barrett, an assistant Extension professor with the Mississippi State University Extension Service Center for Government and Community Development. “Private septic systems that do not function properly or are not installed properly can contaminate nearby water wells or surface water, such as ponds and streams.”

The Mississippi State Department of Health requires homeowners without access to a municipal sewer system to install septic systems to treat household wastewater.

Wastewater from bathrooms, kitchens and laundry rooms enters a large, underground tank where beneficial bacteria break down solid material and harmful bacteria. The treated liquid portion, called effluent, then rises to the top of the tank and drains slowly out to an absorption site through a distribution pipe, called a field line. The distribution pipe should be a maximum of 100 feet long, depending on the site and soil conditions. Soil underneath the distribution site absorbs and filters the water before it enters groundwater, where it is again filtered.

To keep the system working properly, keep solid waste to a minimum and never put paint, pesticides, acids, solvents, oils and degreasers down the drain, Barrett said. Introducing large amounts of wastewater into the system in a short amount of time, such as washing several loads of laundry in one day, can overload the tank. This reduces the time for waste to settle, decompose and absorb in the drainage field.

“Any food left on your plate should go into the garbage,” Barrett said. “Garbage disposals are not necessarily bad. If you have children, a garbage disposal could keep you from having a clogged sink. But just because you can put it in the disposal doesn’t mean it should go down there.”

Only bathwater, human waste and toilet tissue should enter the septic system from bathrooms, Barrett said.

“Many paper products will say they are biodegradable and safe for septic systems,” he said. “But I would be very cautious about flushing anything besides toilet tissue down the toilet. Baby wipes and other types of wet wipes can cause clogs and jams in your pipes or the septic tank itself.”

 Paper towels can cause major problems in a septic system, said Charles Box, who spent more than 25 years manufacturing and installing septic systems in the Oktibbeha County area.

“Paper towels can be a real nightmare if they get into the septic system,” Box said. “Manufacturers now put nylon strips in them to make them more durable, which don’t break down and clog the system.”

Any petroleum product or a large dose of household bleach will kill all of the beneficial bacteria in the tank, said Box, who also is a retired City of Starkville employee.

“A reasonable amount used in a load of laundry is fine and won’t cause problems,” he said. “Phosphates have been removed from most other household detergents and cleaners and are environmentally friendly.”

Some systems require chlorine tablets, and other systems use air pumps to aerate tanks and keep beneficial bacteria alive.

“About the only thing that can cause a major problem within the tank is putting in items that don’t belong, such as fats, oils and grease, which can cause a heavy layer on the surface of the water in the tank and stop up the distribution pipe,” Box said. “Most problems are not associated with the tank.”

Any problems will be evident and can be diagnosed by a reputable plumber, Barrett said.

“If you have an issue with the system, you’ll know it,” he said. “You’ll see a puddle in the yard, or waste will back up into the house. If the bacteria in the tank die, you’ll be able to detect a sewer odor.”

Never drive, park or build on top of the distribution field. These actions can crush the distribution pipe and damage the distribution field, leading to groundwater contamination, Barrett said.

When choosing trees, shrubs or other landscape plants with extensive root systems, plant them at least 20 feet away from any part of the home’s sewage infrastructure.

“Problems usually do not show up right away,” Box said. “But as the plants grow, the roots can invade the sewer, which can lead to expensive repairs. The larger the plant, the further away you should plant it.”

For more information about maintaining a healthy septic system, read Extension Publication 1869, “Managing Household Wastewater,”  and Publication 1871, “Mississippi Home-A-Syst: Managing Household Wastewater.”