Pumping Your Septic Tank

All septic tanks need to be pumped out on a regular basis. Pumping is essential to maintaining a well-functioning system and preventing premature system failure. To understand why, consider what your septic tank does. Your tank's function is to separate solids from liquid flows, and allow only clarified liquid wastewater (after at least 24 hours of settling time) to discharge into your drainfield for final treatment and absorption. Solids are retained in the tank, where heavy solids form the bottom (sludge) layer and lighter solids (e.g., bits of paper, grease and soapsuds) make up the top (scum) layer. While up to 50% of your tank's solids decompose, the remainder simply accumulate.
These accumulated solids can be safely and reliably removed only through regular pumping. Septic system additives will not accelerate decomposition and some (e.g., chemical additives, degreasers) may even wreak havoc on your system and the environment. In the absence of removing solids build-up, your tank's ability to clarify wastewater will be seriously compromised: liquid will not stay in your tank long enough to receive proper treatment, and, over time, carried-over particulate solids will clog your drainfield and cause it to fail.
Pumping should be carried out by a licensed pumper with the proper equipment. Although it is imperative that the actual pumping be left to an experienced, licensed septic professional, there are several important things relevant to pumping that you as the homeowner can (and should) handle. These are as follows:

1. Know where your septic system and replacement area are located and protect them.
2. Practice water conservation and balance your water use throughout the week to keep from overloading the system.
3. Divert water from surfaces such as roofs, driveways or patios away from the drainfield and replacement area
4. Keep traffic, such as vehicles, heavy equipment or livestock off the drainfield and replacement area.

PUMPING FREQUENCY

A septic tank needs to be pumped when the combined (scum and sludge) solids accumulation is equal to 1/3 of the septic tanks liquid volume. How frequently your tank requires pumping is in large part determined by the size of your tank and the number of people living in your household.  However, other factors can influence how frequently your particular tank requires pumping. Use of a garbage disposal is one such factor that has a dramatic impact on pumping frequency. Garbage disposals can deposit significant amounts of undigested solids into your septic tank, increasing scum accumulation by as much as 20%. Households that use garbage disposals will typically need to have their septic tank pumped out 1-2 years sooner than they otherwise would.
Substandard septic tanks (e.g., metal tanks, tanks with capacity below the now-standard 1,000 gallons) should be pumped out every 1-3 years.

For Alternative Systems

If you have an alternative system, chances are you have a maintenance contract! Many localities now mandate maintenance contracts for alternative systems (e.g., fine bubble aerators, recirculating and intermittent sand filters and low-pressure distribution systems). These contracts require regular inspections (e.g., four times per year in the case of fine bubble aeration systems; twice a year for low-pressure systems) by a licensed septic operator, who maintains and tests systems, and periodically reports results to the local authority. Even if your locality does not require a maintenance contract for your alternative system, most experts strongly advise homeowners to purchase one, in view of these systems' greater maintenance needs.
Alternative system installations often come with a two-year maintenance contract between the installer and homeowner. Thereafter, homeowners may be required to continue maintenance contract coverage of their alternative system by signing an agreement with a licensed septic operator. In some communities, homeowners have the option of taking training courses to learn how to perform inspections and maintenance for alternative systems themselves. Most homeowners opt for maintenance contracts instead.
Maintenance contracts for alternative systems generally cost between $150-200, though costs may be higher depending on the individual system.
Finally, a word about telemetry. Broadly, telemetry is a technology used to measure and transmit data from remote locations to a central receiving location where data is recorded and analyzed. Applied to alternative systems, telemetry allows septic operators to monitor the flow, switches, pumps, floats and alarms of remote, scattered systems, and thereby be alerted to developing problems.

For Conventional Septic Systems

Mandated maintenance contract coverage of conventional septic systems remains relatively rare. However, as states and communities that rely heavily on onsite wastewater treatment confront problems caused by improper system care and maintenance, maintenance contracts are increasingly being put forth as part of the regulatory solution.
Establishing a maintenance contract with a licensed septic operator is in fact a very good idea for owners of conventional septic systems. Maintenance contracts ensure annual septic inspections, and scheduled (e.g., every 2-3 years) pumping. Both of these maintenance practices are essential to your system's proper functioning and longevity.
In the absence of a maintenance contract, homeowners should at least keep a maintenance record that both reminds them of when inspections and pumping should be scheduled, and provides information that can prove helpful for septic inspectors/pumpers in diagnosing any system problems when they occur.