Most household septic tanks need pumping every 3 to 5 years. EPA and the Riverside County Department of Environmental Health both give that range, and a few household factors can shorten it.
A typical household tank is pumped every three to five years, according to EPA. EPA also says a typical household system should be inspected at least every three years by a septic professional. Systems with pumps, float switches or other mechanical parts should be inspected once a year.
Riverside County's Department of Environmental Health (DEH) gives the same 3 to 5 year range in its homeowner brochure. It adds that the tank should be serviced more often depending on four things:
More people and more water mean the tank fills faster. EPA says pumping frequency depends on household size, the total wastewater generated, the volume of solids in the wastewater, and the size of the tank.
Indoor water use can reach 70 gallons per person per day, and one leaking or running toilet can add up to 200 gallons per day, EPA reports. Fixing leaks and spreading laundry across the week keeps the drain field from being flooded in one day.
A garbage disposal also matters. EPA says food waste from a disposal builds up as scum and sludge, so a tank used with a disposal needs pumping more often.
Only a professional can measure it. EPA gives three signs that a tank should be pumped: the bottom of the scum layer is within six inches of the outlet, the top of the sludge layer is within 12 inches of the outlet, or sludge and scum fill more than 25 percent of the liquid depth.
Waiting for a symptom is the wrong test. The Riverside County brochure says the most important maintenance step is removing solids and scum before they wash out into the absorption field and before you see any sign that the system is failing.
Riverside County's brochure says a malfunctioning system can cost $3,000 to $7,000 to repair or replace. It puts maintenance at about $250 to $500 every three to five years. EPA's homebuyer guide gives the same $250 to $500 figure from nationwide industry estimates and says replacement can cost thousands to tens of thousands of dollars.
Those numbers are general. A local provider can quote your tank size and access.
Call a licensed septic pro if you do not know when the tank was last pumped, if drains are slow, or if you see wet spots or bright green grass over the system.
No. EPA does not recommend additives for household wastewater because the tank already contains large numbers of microorganisms. EPA says additives can be ineffective or harmful.
Yes. EPA says the tank will need pumping more often if you use a disposal, and it advises limiting its use.
EPA suggests checking property records such as the deed, building permit and design plans. Many tanks have an access riser, often a black or green disc, typically about 10 feet from the building. Riverside County also suggests plot plans, yard lids or manhole covers, or asking an inspector or pumper.
Ask a septic professional to inspect it. EPA lists pumping records, sludge levels and scum thickness among the items an inspection covers, so an inspector can judge whether the tank is due.
Temecula Valley Septic is a free referral service, not a contractor. Request a free quote from a local septic contractor.