Private well test panels: bacteria, nitrate, metals

Last updated: 2026-09-09 · 9 min read · How-to

If you drink from a private well in the US, you are the water utility. EPA rules for public systems do not cover your tap. The practical starting point is a small, certified-lab panel — bacteria, nitrate, plus basic chemistry — then expand for metals and local risks before you buy treatment.

What you’ll learn

The annual baseline EPA and CDC recommend for private wells
What bacteria, nitrate, and metals panels actually measure
When to add arsenic, lead, iron, manganese, or VOCs
Typical cost bands and how to use results before talking to a dealer

The annual baseline (start here)

Both EPA and the CDC recommend testing private well water at least once a year for:

Total coliform bacteria (with E. coli follow-up if positive)
Nitrates (often reported as nitrate-nitrogen)
Total dissolved solids (TDS)
pH

Ask your local health department what else is common in your groundwater (arsenic in some regions, radon, pesticides near intensive farming). Use a state-certified laboratory — strip kits from a hardware aisle are fine for curiosity, not for decisions about infant safety or treatment equipment.

Rule of thumb Order the annual panel from untreated well water (before a softener, carbon filter, or UV unit) unless the lab tells you otherwise. You want to know what the aquifer and casing are delivering — not what the softener already removed.

Bacteria panel: total coliform and E. coli

Total coliform is a screening group. A positive result does not always mean your water is “sewage,” but it does mean the well or sample pathway is not bacteriologically clean. Labs usually reflex to E. coli (or fecal coliform) when total coliform is present.

Result	What it usually means	Typical next step
Total coliform absent	No indicator bacteria detected in that sample	Retest annually, or sooner after floods / well work
Total coliform present, E. coli absent	Possible surface influence, sampling error, or biofilm	Retest carefully; inspect wellhead; consider shock chlorination with guidance
E. coli present	Fecal contamination risk — treat as unsafe to drink	Use bottled or boiled water; call health dept; fix source before long-term treatment sales pitches

Retest after any well repair, pump work, flooding, or a change in taste, odor, or clarity. Recurring stomach illness in the household is also a reason to retest for coliform, per EPA’s private-well guidance.

Nitrate (and nitrite) panel

Nitrate often comes from fertilizer, septic systems, or animal waste. It is colorless and odorless. Public systems use a maximum contaminant level of 10 mg/L nitrate as nitrogen (about 45 mg/L as nitrate). Private wells are not required to meet that number, but it is the health benchmark most labs and health departments use.

Infants under 6 months are the highest-risk group (methemoglobinemia / “blue baby” risk). EPA’s home-testing guidance also flags pregnancy and the first months of a baby’s life for extra nitrate checks.
Test at least yearly; more often near intensive agriculture or if prior results were elevated.
A softener or basic sediment filter does not remove nitrate. Reverse osmosis, anion exchange, or distillation are the usual treatment classes — size them from a real lab number, not a sales demo.

Metals and related chemistry

“Metals” is not one SKU. Build the add-on list from symptoms and location:

Situation	Ask the lab to include
Staining, metallic taste, laundry marks	Iron, manganese, copper
Old plumbing, soft/acidic water, corrosion	Lead, copper, pH, corrosivity indicators
Known regional geology (parts of New England, Midwest, Southwest, etc.)	Arsenic (and ask health dept about local lists)
Mining history nearby	Metals suite, pH, corrosion
Hardness / softener shopping	Hardness, iron, manganese (iron/manganese foul many softeners)

EPA’s private-well tables also map nearby land uses to extra analytes: pesticides near farms; VOCs near gas stations, dry cleaners, or fuel tanks; chloride and sodium near salted roads or seawater. Don’t buy a “100-contaminant” kit because a flyer scared you — match the panel to risk, then keep the annual baseline going.

Typical cost ranges (US, estimates)

Prices vary by state, courier fees, and whether the county subsidizes bacteria/nitrate. Treat these as planning bands, not quotes:

Health-department bacteria + nitrate: often free to about $40–$80
Certified-lab annual baseline (coliform, nitrate, pH, TDS): often about $50–$150
Baseline + metals / arsenic / hardness package: often about $150–$350
Targeted VOC or pesticide suites: can run higher; order only with a clear local reason

Ask whether shipping ice packs and overnight return are included. Bacteria samples have short hold times — follow the bottle instructions exactly.

How to order without getting upsold

Call a state-certified lab or county environmental health first. EPA’s Safe Drinking Water Hotline (800-426-4791) can point you to your state certification officer if you need a lab list.
Say you want the annual private-well baseline (coliform, nitrate, pH, TDS) plus any metals your county flags.
Request bottles and written sampling instructions before you collect. Wrong bottle or wrong faucet ruins the spend.
Sample the raw well (or a dedicated untreated tap) for the first panel.
Keep the PDF report. You need numbers — not a dealer’s verbal “your water is bad” — before you buy equipment.

Affiliate / kit note Mail-order well kits can be convenient when they use certified labs. Prefer kits that name the lab, list exact analytes, and ship sterile bacteria bottles with clear hold-time rules. We may later link specific kits with an affiliate disclosure; until then, start with your county or a state-certified lab.

Reading results before treatment shopping

Compare numbers to EPA primary standards (health) and secondary standards (taste, staining) even though private wells are not regulated the same way as city water.
Bacteria problems are usually a well integrity or disinfection issue first — not a reason to jump straight to a whole-house softener.
High nitrate needs a treatment class that actually removes nitrate, plus a retest plan.
Iron/manganese/hardness drive equipment choice and media fouling; bring the lab sheet to any Water Quality Association (WQA)-listed dealer and ask how each number changes the proposal — see WQA dealers vs big-box softeners.

Red flags

Walk away if A salesperson refuses to look at a certified lab report; pushes a softener as the fix for bacteria or nitrate; quotes only after an in-home “free test” with no written analytes; or pressures same-day financing before you can retest or get a second opinion from the health department.

FAQ

Is one “complete well panel” enough forever?

No. Keep the annual bacteria/nitrate/pH/TDS baseline. Retest metals or specialty analytes when geology, land use, plumbing, or symptoms change — or when a previous result was elevated.

Can I use city-water standards on a private well report?

Yes, as a reference. MCLs and action levels are the clearest health benchmarks most homeowners have. Your state or county may publish private-well guidance that is stricter or more local.

Should I test after installing treatment?

Yes — once for proof the unit works on the problem you bought it for, then on a schedule the manufacturer or your health department recommends. Keep a raw-well sample in the record so you can tell aquifer changes from filter failure.

Are WellPath listings paid?

Featured or referral placements are labelled when used. Listings are informational, not endorsements. Always verify lab certification and dealer credentials yourself.

Next steps

Order this year’s baseline panel, collect it with clean technique (how to sample without contaminating the bottle), save the PDF, learn how to read action levels, compare WQA dealers vs big-box softeners, then browse WellPath listings for labs and WQA-oriented treatment pros in your area — or contact us if a provider is missing. More guides on the guides index.

Disclosure: WellPath may earn lab-kit affiliate commissions or dealer lead fees. This page is general guidance, not medical or legal advice. Confirm analytes and action levels with a state-certified lab and your local health department.