The systems view
Whole-house water treatment for Maine wells
Some Maine wells fail one test. Plenty fail three at once: arsenic with uranium, iron with bacteria, radon over everything. The same bedrock that gives Maine about one in 10 wells over the federal arsenic standard, per USGS, also produces radon and uranium, and a peer-reviewed Maine study found 20 percent of wells within granitic plutons exceeded the state's 30 ug/L uranium guideline, per Yang et al.
A multi-problem well does not need a pile of gadgets. It needs a treatment train: stages in a deliberate order, each protecting the next, all designed from one full lab panel. This page explains the order and the logic, with honest cost ranges for each stage.
One panel before any design
Combined systems get designed from a single comprehensive lab panel, not from symptoms plus a hunch. The reason is arithmetic: every stage is sized by numbers (concentrations, pH, hardness, flow), and every sequencing decision is driven by how those numbers interact. Testing piecemeal, one analyte per crisis, produces equipment bought in the wrong order. About half of Maine households are on private wells, per the Maine Geological Survey, and the state lab sells a comprehensive kit built for exactly this: one sampling, every major analyte, one report. The testing page covers ordering it, and the results explainer turns the report into plain language.
The treatment train, in order, with reasons
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1. Sediment filtration
Grit and fines come first because they wear valves, clog media beds, and shade UV lamps. A simple cartridge here protects every dollar spent downstream.
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2. Radon aeration, when the number calls for it
Aeration strips radon gas near the point of entry and vents it above the roof, before the water spreads through the house. EPA lists aeration as the best available technology for radon in water. One design note a professional weighs: aeration also oxidizes dissolved iron, which can help or complicate the next stage. Details on the radon page.
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3. Oxidation plus filtration for iron and manganese
The metals come out here so they cannot foul softener resin, coat RO membranes, or film the UV sleeve. Skipping this stage on an iron-heavy well quietly ruins the stages behind it. The equipment is covered on the iron and manganese page.
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4. Softening or specialty ion exchange
Hardness gets exchanged here, and wells over Maine's 30 ug/L uranium guideline can carry a dedicated anion exchange stage, cited around $3,000 installed plus roughly $500 per year in operation, per Wellowner.org.
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5. Reverse osmosis at the kitchen tap
The drinking water polish. An under-sink RO unit backs up the whole-house stages for the water you actually swallow, the common design against arsenic and PFAS, and it lives longest when stages one through four already tamed sediment, iron, and hardness.
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6. UV disinfection, last
UV is designed to inactivate bacteria, viruses, and cysts, and it demands clear water, which is precisely what the train has produced by this point. Sizing, NSF/ANSI 55 certification, and prefiltration rules are on the bacteria and UV page.
Why sequencing is design work, not shopping
Every stage changes the water the next stage receives, and the interactions cut both ways. Aeration that strips radon also precipitates iron, which a downstream filter must be sized to catch. Hardness that skips a softener shortens RO membrane life. Iron that skips its filter stains the softener resin and shades the UV lamp. Order mistakes do not fail loudly on day one; they fail as maintenance bills in year two. This is the strongest argument for one professional designing from one panel, rather than three vendors each selling their own box.
Budget-wise, trains phase well. Health numbers come first: bacteria, arsenic, radon, uranium. Nuisance stages follow when the budget recovers. For eligible homeowners, MaineHousing's Well Water Abatement program can help with contaminated wells; check its current funding status. The stage-by-stage price landscape, with every source, is in the Maine treatment cost guide.
Ongoing costs deserve the same one-designer treatment as the install. A full train carries several recurring lines at different rhythms: arsenic media at $200 to $300 per year per the EPA-hosted fact sheet, roughly $500 per year for uranium anion exchange, a $50 to $150 UV lamp annually, softener salt, and cartridge changes. A good quote states all of it up front, so the year-five cost of the system is a known number, not a series of surprises. And the feedback loop stays the same as everywhere on this site: retest the treated water yearly for bacteria and nitrates and on the state's three-to-five-year cycle for the bedrock analytes, because the panel that designed the train is also the only honest way to confirm the train still works.
Put the whole panel in front of one designer
If your report has more than one bad line, resist solving them one purchase at a time. Tell us your town and what the panel found, and we connect you free with an independent Maine professional who designs combined systems from lab numbers, sequences the stages, and quotes the whole train with its maintenance costs in the open.
No panel yet? Start on the testing page, or submit the form and say so. How the free matching works is on the how we make money page.
Questions Maine well owners ask
- Does a multi-problem well need every treatment stage?
- No. The treatment train is a menu ordered by logic, not a checklist to buy. A professional builds from the lab panel: only the stages your numbers call for, in the order that protects each stage from the ones upstream. Plenty of Maine wells resolve with two stages, and some genuinely need five.
- What order do treatment stages go in?
- The common logic: sediment filtration first, radon aeration near the entry with its vent, oxidation plus filtration for iron and manganese next, softening or specialty ion exchange after that, then reverse osmosis at the kitchen tap for drinking water polish, and UV disinfection last, once the water is clear enough for light to work.
- Can a combined system be phased over time?
- Yes, and phasing is often the sane budget path. Health-driven stages come first: bacteria disinfection, arsenic, radon, uranium. Nuisance stages like iron filtration and softening can follow later, as long as the early stages are designed with the later ones in mind. That forward planning is exactly why one designer should see the whole panel.
- What does a whole-house combination system cost?
- It is the sum of its stages, each with cited ranges: roughly $1,500 to $4,000 for an iron filter, $2,000 to $3,000 installed for whole-house arsenic media, $6,000 to $8,000 for radon aeration regionally, about $3,000 for uranium anion exchange, $700 to $2,500 for UV, and $150 to $1,300 plus install for under-sink RO. Few wells need all of it.
- Should I hire one professional or several?
- One designer for the train, even if trades split the installation. Stages interact: aeration changes iron behavior, hardness shortens membrane life, and UV depends on everything upstream. A single professional working from a single full lab panel owns those interactions. We match you with an independent local pro who works that way.