How well water treatment works
Water from a New Hampshire bedrock well often carries arsenic, radon, iron or hardness from the rock around it. Set the results of a water test, then follow the water through the treatment line and see what reaches the kitchen tap.
- Water
- Hardness
- Iron
- Arsenic
- Radon
- Coliform bacteria
- Sediment
Your water test, straight from the well
At the kitchen tap
- Hardness0.2 gpg
OK: above 7 grains per gallon is hard water
- Iron0.1 mg/L
OK: above 0.3 mg/L stains fixtures and laundry
- Arsenic0.5 ppb
OK: New Hampshire's limit for public water is 5 ppb
- Radon270 pCi/L
OK: 4,000 pCi/L is the level the EPA proposed for water
- Coliform bacteriaAbsent
OK: any is a fail
- SedimentNone
OK: visible grit or cloudiness
- Water pressureNormal
You can't see or taste the worst of it.
Iron stains and hardness scale show up on their own. Arsenic, radon, uranium and bacteria don't, and they are the ones that matter for health. A full test from a state-accredited lab is the only way to know what's in the water, and a second test after the treatment is the only way to know it's working.
Test when you buy a house, every few years after that, and whenever the water changes. Test the treated water every year if you have an arsenic filter or a UV light.
How the well pump worksHardness
Calcium and magnesium. Not a health problem, but it scales up water heaters, fixtures and dishwashers and leaves spots.
Iron
Leaves orange stains and a metallic taste. Manganese often comes with it and stains black.
Arsenic
Comes from the bedrock itself. It has no taste, color or smell, and long-term drinking raises the risk of several cancers. The only way to know is a test.
Radon
A radioactive gas from granite. It escapes from the water into the air when you shower or run the dishwasher, and breathing it raises lung cancer risk.
Coliform bacteria
A sign that surface water is getting into the well, often through a damaged cap or casing. E. coli means sewage.
Sediment
Sand, silt and rock fines. It wears out valves and fixtures and shields bacteria from the UV light.
Each problem has its own fix.
No single filter takes out everything, so a treatment line is built from the test up, and the order matters: sediment comes out before it can clog anything, and the UV light goes last so it shines through clear water.
| Problem | Treatment | Upkeep |
|---|---|---|
| Radon | Aerator that vents the gas outside | Fan and vent checks, tank cleaning |
| Sand and silt | Sediment filter | New cartridge every few months |
| Hardness, some iron | Water softener | Salt, and a yearly check |
| Arsenic | Media filter, or reverse osmosis at the kitchen sink | Test every year, replace the media when it's used up |
| Bacteria | UV light, after the other treatment | New lamp every year, clean the sleeve |
Six common service calls.
Treatment fails quietly. Some faults show up as stains or low pressure, and some only show up on a lab report. Pick one to see what gets through to the tap.
Salt bridge in the brine tank
"The water's getting spots and scale again, but the salt tank is full."
Humidity makes the salt fuse into a hard crust above the water in the brine tank. The tank looks full, but the softener can't make brine, so the resin never regenerates and hard water goes straight through.
UV lamp past its life
"Our water test came back positive for coliform, but we have a UV light."
A UV lamp keeps glowing long after it stops putting out enough ultraviolet light to kill bacteria. They need replacing every year, and the quartz sleeve around the lamp needs cleaning.
Arsenic media used up
"We haven't tested since the filter went in years ago. Should we?"
The arsenic filter holds a fixed amount of arsenic. When the media is used up, arsenic passes straight through, and because you can't taste or see it, only a test after the filter catches it.
Bypass valve left open
"Everything was fine until the plumber came. Now the water smells and it's staining again."
Every treatment system has a bypass valve so it can be serviced. After a repair or a plumbing job it gets left in bypass, and untreated water goes to every tap in the house.
Clogged sediment filter
"The water pressure has been dropping for a few weeks. The shower is terrible."
The cartridge catches sand and silt until it's packed solid. Water squeezes through slowly, the pressure at the taps drops, and the shower weakens when another tap is on.
Radon aerator fan failed
"The radon system is making a different noise, or no noise at all."
The aerator sprays the water into a tank and a fan blows the radon out through a vent pipe. When the fan fails, the radon stays in the water. Many units shut the water off instead, which gets noticed faster.
Where AI helps the office and the trucks.
A treatment business runs on test results and schedules: which customers are due for a lamp, a cartridge, new media or a retest. Most of that is reading and remembering, which software does well, and it leaves your people more time in basements.
A test result that turns into a proposal
A homeowner sends the lab report. AI reads the numbers, flags what's over the limits, and drafts the system and the explanation for your tech to check before it goes out.
Custom AI agentsMaintenance nobody forgets
Every customer's lamp date, cartridge schedule, media age and last test, with reminders that go out on time and salt deliveries booked by text.
Custom AI agentsService calls with answers already in
Intake asks for a photo of the equipment and the valves, what changed, and when the last test was. A bypass valve left open gets fixed on the phone.
AI Cowork training
This page shows a typical treatment line for a bedrock well, simplified for learning. Removal rates and reference levels are approximate and for illustration, not a design. Have your water tested by a state-accredited lab, and have treatment sized to your own results by a qualified water treatment professional.
