Well & Septic HQ
30-second answer
The septic calendar is short enough to print. A professional inspection at least every three years, pumping typically every three to five, and one well water test a year for bacteria and nitrate Source 1: US EPA, SepticSmart homeowner guidance Source 5: National Ground Water Association, Well Owner's Guide 2021. If your system has a pump, float switch or control panel, inspection is annual instead Source 1: US EPA, SepticSmart homeowner guidance.
The rest is what no calendar covers: the four things to ask for in writing at the service visit, and the photographs to take while the lids are open. None of it requires opening anything yourself. Anything at an open lid is the pumper's work. The reasoning behind every interval is in the maintenance guide.
The checklist
Print it, hang it inside a cupboard door, and write dates on as they happen.
Every year
- Book the well water test: bacteria and nitrate. Same month each year Source 5: National Ground Water Association, Well Owner's Guide 2021. The water testing guide covers what else people add, and why they disagree.
- Walk the drainfield. Wet spots, unusually green patches, and animals living in the cover Source 2: University of Minnesota Onsite Sewage Treatment Program.
- Nothing parks, drives or is stored on the drainfield, and no water-seeking tree near it Source 2: University of Minnesota Onsite Sewage Treatment Program.
- Pump, float switch or control panel? Book the annual inspection Source 1: US EPA, SepticSmart homeowner guidance.
- File the year's paperwork with the system records Source 1: US EPA, SepticSmart homeowner guidance.
Every three to five years
- Inspection at least every three years; pumping typically every three to five Source 1: US EPA, SepticSmart homeowner guidance.
- Pump on the measurement, not the calendar. Any one of the EPA's thresholds is enough: scum within six inches of the outlet bottom, sludge within 12 inches of it, or the two over 25 percent of liquid depth Source 1: US EPA, SepticSmart homeowner guidance.
- Know where the tank and both lids are before the truck arrives. Start with the permit sketch at the county health department.
Every visit: four lines, in writing
- Sludge and scum depths measured before pumping. Without them the next visit is another guess.
- Both compartments pumped through their own access lids, rather than one lid serving both.
- Condition of the inlet and outlet baffles. They corrode, and it is the failure caught early and fixed cheaply.
- Effluent filter: present, cleaned, and whether it needs replacing.
The pumping cost guide covers what those lines cost. This page carries no prices on purpose: an interval holds for years, a price does not.
All year, at the sink
- Garbage disposal: it shortens the interval. Using one can put up to 50 percent more solids into the tank Source 3: National Environmental Services Center, West Virginia University.
- Laundry spread through the week, not one day: up to 53 gallons arrives with each load Source 3: National Environmental Services Center, West Virginia University Source 1: US EPA, SepticSmart homeowner guidance.
- Fix running toilets. One can add as much as 200 gallons a day Source 1: US EPA, SepticSmart homeowner guidance.
- Water softener backwash. Minnesota says route it out; the EPA says ask a licensed plumbing professional. Same mechanism, different instruction Source 2: University of Minnesota Onsite Sewage Treatment Program Source 1: US EPA, SepticSmart homeowner guidance.
- Down the drain: human waste and toilet paper only. No grease, wipes, solvents, paints, pesticides, drain cleaners, diapers, cat litter or cigarette butts Source 1: US EPA, SepticSmart homeowner guidance Source 2: University of Minnesota Onsite Sewage Treatment Program.
What to photograph before and during the visit
Four of these five exist only while somebody else has the lids off.
- The lids, closed, with a landmark in frame. A house corner or fence post, plus the distance. This is what saves the next crew probing the lawn.
- Each open lid, and which compartment it serves.
- The inlet and outlet baffles, for the next report to compare against.
- The effluent filter, out and dirty, then back in.
- The finished invoice, with the four lines above filled in.
Keep them with the maintenance records the EPA asks you to hold anyway Source 1: US EPA, SepticSmart homeowner guidance. At resale they are the difference between a history and a story.
Who decides your interval
Not this page. Many counties set a maximum interval by rule. They require a pump-out on that schedule whatever your sludge depth says. In Texas, on-site sewage facilities fall under 30 TAC Chapter 285, administered locally by an authorized agent Source 4: Texas Commission on Environmental Quality, 30 TAC Chapter 285.
Requirements vary by county. Your county health department has the final word on permits, inspections, service contracts, and what is allowed on your property.
Common questions
How often should a septic tank actually be pumped?
The EPA's guidance is an inspection at least every three years and pumping typically every three to five. The range is wide because it is set by how fast solids build up in your tank, which is why the depths on your last invoice are worth more than any published interval.
What is the measurement that says it is time to pump?
The EPA gives three, any one of which is enough: the bottom of the scum layer within six inches of the outlet bottom, the top of the sludge layer within 12 inches of it, or the two over 25 percent of liquid depth. Ask for those numbers, not a date.
Does an aerobic or pump-assisted system need a different schedule?
Yes. The EPA's guidance is that alternative systems with electrical float switches, pumps or other mechanical components should be inspected more often, generally once a year. If yours has a control panel or alarm, treat annual as the baseline and ask the county what a service contract must cover.
How often should I test the well water?
Once a year for bacteria and nitrate. That is the annual health panel every authority agrees on, and booking it in the same month is what stops it sliding. What else belongs in the sample is disputed, and the well water testing guide sets out who recommends what.
Can I just print this and hand it to the pumper?
That is what it is for. The four lines under the service visit turn a pump-out into a next interval: depths before pumping, both compartments through their own lids, baffle condition, and the effluent filter. A visit with none of them recorded leaves you guessing again in three years.
Sources
- SepticSmart homeowner guidance: how to care for your septic system, and the SepticSmart Homeowner Guide. US Environmental Protection Agencyaccessed Jul 2026
- Septic system care and maintenance, including monitoring, vegetative cover and water-softener routing. University of Minnesota Onsite Sewage Treatment Programaccessed Jul 2026
- The Care and Feeding of Your Septic System (solids loading and household water volume). National Environmental Services Center, West Virginia Universityaccessed Jul 2026
- 30 TAC Chapter 285, On-Site Sewage Facilities (rule text). Texas Commission on Environmental Qualityaccessed Jul 2026
- Well Owner's Guide, 2021 edition (annual bacteria and nitrate testing recommendation). National Ground Water Associationaccessed Jul 2026