How often should you test your well water?

Why bother

You can't see contamination. Test for it. This is an essentials-tier job. Skip it and you're inviting the expensive kind of problem, or the dangerous kind.

What the job involves

1. Decide what you're testing for. At a minimum it's the EPA's annual four: coliform bacteria, nitrates, total dissolved solids, and pH. If there's a gas station, farm, mine, or some new mess nearby, add metals, VOCs, or pesticides to the list.
2. Get a sample kit from a state-certified lab. Ring the county health department first, mind: a lot of them do the bacteria and nitrate test subsidized or free, and some post you the bottles and a return mailer.
3. Collect the sample exactly as the lab says. Sterile bottle, the tap they tell you, no aerator in the way. Sloppy sampling gives a wrong answer, so follow the sheet and get it back to them promptly.
4. Read the report against the EPA limits (zero coliform, nitrate under 10 mg/L) and act on anything over. That means disinfect, fit treatment like UV or reverse osmosis, or hunt down the source: a cracked well cap, a septic leak next door.

Do it yourself, or pay someone?

DIY for a quick screening, a certified lab for anything that counts. Home strip kits run about $15 to $30 and are fine for a between-test check, but they're easy to misread and nobody accepts them for a sale or a health call. The annual lab test is roughly $40 to $100 for a basic coliform and nitrate panel, $200 to $350 for the full works; a well inspection with testing bundled in is about $300 to $600. Check the county health department first, plenty do the basics for nothing.

What skipping it costs

$40 to $350 a year is the test you skipped. The trouble is most well contaminants have no taste, no smell, no color, so an untested well can hand the house unsafe water for years and nobody the wiser. Coliform and E. coli bring on the acute gut illness; nitrate over the EPA's 10 mg/L limit can cause methemoglobinemia, blue baby syndrome, in a bottle-fed infant under six months, which can be serious or fatal. Once a problem's confirmed you're buying the treatment system to fix it, a one-time UV disinfection or reverse-osmosis install of roughly $1,000 to $3,000 and up. Catch it on a yearly test and it's the cheap end. Find out after someone's ill, or after a contamination plume has spread, and it isn't.

Signs it's overdue

• Any change in the water. A salty, metallic, or chemical taste, a rotten-egg sulfur or detergent smell, or it runs red, brown, or cloudy. Worth knowing the other way too: most contaminants are invisible, so clean-looking water is no proof it's safe.
• Something's just happened to the well. Spring flooding over the wellhead, a broken or missing well cap, recent repairs, or a new septic system or farm operation gone in nearby.
• It's simply been more than a year, or there's a reason to test now: someone in the house pregnant or nursing, or an infant on formula. The EPA flags those as test-promptly cases.

When to start thinking about it

Give yourself about 7 days' notice. That's when Grumpty starts grumbling, so it doesn't land on you the day it's due. Mark it done and Grumpty sets the next one, every 12 months, so you can go back to forgetting it exists.

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