Nobody wants to flush a toilet into a drinking watersupply. It’s important to install and maintain septic systems properly to avoid polluting groundwater. Typical septic systems have three parts:
Septic tank: Household wastewater is collected and stored in a concrete, metal, plastic, or fiberglass tank just outside the house. The tank stores solids that float to the top or settle to the bottom. The remaining liquid flows into the drainfield. If tanks are not pumped periodically, floating solids may overflow into the drainfield and clog pipes and soil.
Drainfield: The drainfield is made up of a grid of pipes that spread the liquid over a wide area. Holes in the pipe allow liquid to leach into the soil.
Proper soil: The soil is the single most important purifying step in a septic system. Soil microorganisms and plant roots need air and time to break down bacteria, viruses, and nutrients and purify liquid waste. Septic systems fail when soils are too wet, clogged, or compacted to absorb the liquids or too well-drained to have enough time to purify liquids.
Septic System Etiquette
Contrary to popular belief (or wishful thinking), septic systems are not maintenance-free. Half of all septic system failures are due to poor maintenance. Signs of neglect include backed-up plumbing, lush grass over the drainage field, and smelly seepage. Long before you see these signs, the system may discharge untreated sewage into the groundwater and into your well!
Extend the life of your septic system by the following:
Inspect the solids in septic tank annually.
Insert a probe into the inspection port in the tank lid. If solids (usually black specks) cover the probe more than one third of the tank depth, it’s time to pump.
|Tank Size (gal)||Number of people in household|
Pump the tank every 1 to 5 years.
Decide the pumping frequency based on the solids inspection or use the Tank Pumping Frequency chart as a guide.
Avoid garbage disposals.
A garbage disposal can add up to 25 percent of the solids in a tank.
Keep slow-to-decompose items out of the tank.
This includes coffee grounds, facial tissues, cigarette butts, disposable diapers, sanitary napkins, and wet-strength towels. Use toilet paper that breaks down easily when wet (color doesn’t matter).
Keep harsh cleaners, solvents, and paints out of the tank.
Normal amounts of bleach, detergent, drain cleaners, and toilet bowl deodorizers will not stop the natural breakdown of solids in the tank. Excessive amounts will. The system is not designed to purify these contaminants. Follow label directions for proper disposal. Take advantage of “household chemical days” at a local landfill.
Avoid products that claim to clean septic systems.
There’s little evidence that these products work. What’s more, some may be carcinogenic and
move into your groundwater.
Use less water.
Give time for solids to settle in the tank and avoid flooding the drainfield. Install showerheads, faucets, and toilets that use less than 3 gallons of water per minute or per flush.
Keep vehicles, trees, and roof water away from the drainfield.
Vehicles may compact soils and damage drainfield pipes. Tree roots clog pipes and roof water saturates soils.