With city dwellers moving in droves to the suburbs and beyond in search of a little open space, many find that their new homes are equipped with septic systems for waste removal. Such systems may be a good alternative to municipal systems, but they do require routine maintenance. A key part of that maintenance involves emptying the septic tank periodically, said Kansas State University Research and Extension engineer, Morgan Powell.
"If a homeowner knows in the fall that it's about time to pump the septic tank and she has a houseful of people coming for the holidays, she would be well-advised to take care of the septic tank before the holiday," said Powell, a water quality specialist with K-State Research and Extension. "That's an easy way to help avoid failure (backup in the house or surfacing in the yard) of the system at a time when it will be needed the most."
Regular septic tank pumping can help keep the entire system operating for a longer time. The alternative could be slow-running drains, sewage backup in the home, wet, smelly areas in the yard, and the expense of replacing a system, he said. Some owners speak with pride about how long they avoided pumping their tanks, usually the length of time that it took for the septic system to fail, instead of focusing on maintenance to keep the system working as long as possible.
"It's the difference between saying 'I didn't change the oil in my car and it ran 50,000 miles before the engine seized up' and 'I routinely changed the oil in my car and it has run for nearly 300,000 miles,'" he said.
Septic systems, which include a tank and a soil absorption field (laterals), are typically installed when there is no access to municipal sewage systems. The tank should remove, store, and decompose as much of the solid part of a home's or business' wastewater as possible before the clear effluent (still sewage) goes to the absorption field for final treatment and dispersal.
Powell says the state minimum standard is a 1,000-gallon septic tank for a three-bedroom house and at least a 1,250-gallon tank for a four-bedroom house. If a garbage disposal is used, a larger tank should be used.
How often the tank needs pumping depends on how large it is, and how many people are using it as well as what is put down the drain. Every three to five years is a typical pump interval.
There are guidelines, however. If six people live in a house with a 1,000-gallon tank, it should be pumped about every 1.5 years. But if six people live in a house with a 2,000-gallon tank, it should be pumped every 3.7 years.
Properly-sized tanks have enough space for sludge to accumulate for several years, but Powell said that pumping them at regular intervals helps prevent premature failure of the soil absorption field.
Powell also recommends using water conservatively and reducing the amount of surface water entering the absorption field as much as possible by diverting runoff from impervious surfaces away from the absorption field. A good stand of cool season grass over the field helps with moisture evaporation.
For more detailed information on septic system installation and maintenance, publications are available at K-State Research and Extension county and district Extension offices throughout Kansas and on the website: www.oznet.ksu.edu/library/. Enter MF947 before pressing "Go."
Tips for maintaining and prolonging the use of a septic system:
-- Do not use additives. Many claim to make the system operate better or eliminate the need for pumping, but in fact, they may remove some of the material in the septic tank and force it into the absorption field, which works against the purpose of the system. Also, some chemical additives are toxic and can harm the environment.
-- Garbage disposals do not really dispose of solids. While they do grind them up so they go down the drain easier, these solids accumulate in the septic tank and will speed up the frequency with which tank pumping is necessary.
-- Avoid putting certain items down the drain including fats, oils, grease, eggshells, coffee grounds, facial tissues and cigarette butts. They do not decompose in the septic tank and take up valuable sludge storage capacity.
-- Liquid laundry detergents are preferable to powdered forms.
-- An effluent filter improves the septic tank's efficiency of solids removal. It is a screened device in the outlet of the tank that protects the soil absorption field from solids carryover.
-- Plant trees at least 25 feet away from the absorption field and remove any that are closer. Tree roots can damage the septic system.