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Pumping Tanks

Septic tank advice

Richard Trehewey holds a toilet

How frequently should a septic tank be pumped out? We have lived in our house for four years and don't know when our tank was last pumped.
— Edwin, Winchester, VA


Richard Trethewey replies: Most tanks should be pumped about every three years, so it's time to have yours taken care of. If you wait too long, the solids that normally drop to the bottom of the tank will have nowhere to go but into your leach field, which is meant to absorb liquid waste only. You'll end up writing big checks to dig up your yard and replace the clogged field.
The timing for the pumping session after this one will depend on how big the tank is (your town should have a record of the tank size) how much you use it, and how much solid waste you generate. If you have a small or average-size tank, a garbage disposer, a big family, or entertain a lot, go for a shorter time between pumpings. But if you have a large tank or a small family, travel a lot, and compost all your kitchen scraps, you can probably go longer. Ask the pumper to assess how full the tank is the next time you pump it out and then schedule accordingly. In any case, err on the side of more often rather than less. Pumping a little early won't cost much, but leaving the job until the tank overflows will ruin your whole day.


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