How to Tell If a Septic Needs a Pump

Homes in rural areas far from municipal sewer systems must rely on septic tank systems to treat household wastewater from toilets, tubs and sinks. Septic tanks rely on an enzymatic bacterial action to digest the waste. Indigestible solids in the waste fall to the bottom of the tank as sludge while liquid runs out to a drain field. The sludge eventually builds up to a point where it can interfere with the tank's action unless it is pumped out.

Septic opening
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Septic tank risers facilitate access for inspection and cleaning.

Telltale Signs

One sure sign that your septic tank requires pumping is water pooling on the surface above the tank and its drain field. A full septic tank can send solid waste into the drain field, clogging leach-field pipes. With no place to go, the wastewater seeps out of the tank and pipe joints in the drain field and rises to the surface. The septic tank eventually becomes so full that it cannot accept any more wastewater. The result is a backup of black, foul sewage into toilets, sinks and bathtubs.

Odor and Greenery

Early signs of an overly full septic tank include foul odors from household drains, the drain field and the area above the tank and incredibly lush and green grass growth in those same areas. The sewage stink is a strong indicator that wastewater is backing up requiring a pump out of the septic tank sludge. The excessively lush grass growth results from grass plants taking up the nutrient-rich wastewater.

Pumping Interval

The time interval between septic tank pump outs typically is three to five years. But large families, smaller tanks, and heavy bathroom and sink use can substantially reduce that interval. Many septic tank cleaning companies offer inspection services and can tell you if and when your tank requires emptying. But before you call for an inspection, locate the septic tank and the inspection ports, digging into the ground if necessary.

Problem Causers

A septic tank is designed to dispose of human excrement, toilet tissue and bathwater. Dumping other things into toilets and drains can poison the beneficial septic tank bacteria that digest waste, greatly shorten the interval between septic tank pump outs and lead to premature septic system failure. Don't dispose of hazardous materials such as paint thinners, motor oil or pesticides by flushing them down the toilet. Don't flush non-soluble items such as feminine products, cigarette butts, disposable diapers or kitty litter. And avoid using an in-sink garbage disposal for leftover foodstuffs. Septic tanks can't digest uneaten food.