The honest answer is that it depends on where the water comes from. A home on town water and a home on a private well are two different situations, with different things worth checking and different fixes at the end of it. It is a fair thing to wonder about, and most of what comes back when you search it was written by somebody with a system to sell. This is what we actually see in Metrowest houses, what a test can tell you, and what each piece of equipment really does.
Everything else on this page follows from this one question, so answer it first. If you get a water bill from the town, you are on a public water system. If you have a well and a pump, you are not.
On town water, the system is regulated. It is tested on a schedule against state and federal standards, and it is required to report the results to the people drinking it. That report is published every year for customers, and it is free. You do not have to test anything to find out what your town delivers — you have to read it.
On a private well, none of that applies. No agency tests your well, no report arrives in the mail, and nobody is watching the water on your behalf. The quality of that water is the responsibility of whoever owns the house. That is not a scare — it is just how the line is drawn, and it means a well owner has to go looking rather than waiting to be told.
Metrowest is split down the middle on this. Holliston, Framingham, Natick, and Ashland are largely town water. Sherborn, Dover, Wayland, and Upton are heavy on private wells, and those are the houses where we do the most water work. If yours is one of them, our Metrowest private well guide covers what the state requires, what the bedrock around here has to do with it, and what treats what.
There are three honest paths, and which ones apply to you depends on the answer above. Be clear-eyed about what each one covers, because they do not overlap as much as people assume.
Start with your town water department, or with the annual water quality report your public water system publishes for its customers. That is where PFAS results live, and it is where you find out whether your town adds fluoride. It costs nothing and it is specific to the water coming down your street. For current state guidance, mass.gov is the source; federal drinking water standards are set separately, and epa.gov is where to check those.
An independent certified lab is the answer, and for some items it is the only answer. PFAS and lead in particular require a certified lab — they cannot be read off a field kit, and for lead the sampling method itself changes the result. A lab will tell you what to collect and how.
We collect a water sample and send it out through our supplier to a testing company. The results come back to you along with recommendations, and that panel is the standard water-chemistry work — hardness, iron, and the like. We also check the basics on-site while we are at the house: hardness, iron, pH, and chlorine.
Being plain about the limit of that: the panel we send out is water chemistry. It is not a PFAS test, not a fluoride test, and not a lead test. If those are what you are after, the paths above are the ones to take. We would rather point you at the right lab than sell you a number we did not measure.
A large family of manufactured chemicals used in consumer and industrial products, which persist in the environment rather than breaking down. Massachusetts regulates six of them together for public water systems and sets a combined limit; private wells are not covered by that standard. The whole picture is in our PFAS in Massachusetts drinking water guide.
Lead does not normally originate in the water source. It comes from the plumbing — service lines, older solder, and brass fixtures — which is why homes built before 1986 are the higher-risk group in Massachusetts. Levels also swing with how long the water has been sitting still in the pipes, so the sampling method matters and a reliable answer takes a certified lab. The full version is in our lead in drinking water guide.
Some Massachusetts public water systems add fluoride and some do not, and your town water department or the annual water quality report will tell you which camp you are in. Whether a household wants it out of their drinking water is their own call. If you do want it out: reverse osmosis, activated alumina, and bone char remove fluoride, and standard carbon filters — including typical pitcher and faucet filters — do not. The mechanics are laid out in our guide to removing fluoride from drinking water.
This is the bulk of what we actually treat in Metrowest, and it is the part homeowners can see for themselves: scale on fixtures, spotting on glassware, stiff laundry, reddish staining from iron, and dark staining from manganese. Hardness also puts scale inside a water heater, which shortens its life. Detail on the equipment side is on our water filtration and softening page.
Every one of these is good at something and useless at something else. Reading this list once saves most of the money people waste on water treatment.
There are two places to treat water, and they do different jobs. Point of entry is whole-house equipment plumbed in at the main — softeners, carbon filters, iron filters, UV, sediment pre-filters, acid neutralizers. It treats every tap in the house, including the shower, the laundry, and the hose bib. Point of use is a reverse osmosis system under the kitchen sink with its own drinking faucet. It treats that one tap and nothing else.
That split has a practical consequence worth stating plainly: PFAS, fluoride, and lead get handled at the kitchen tap with reverse osmosis, not across the whole house. Whole-house filters are generally not sufficient for lead — lead is addressed at the drinking tap. We do not install whole-house reverse osmosis. The reasoning behind that is laid out in our whole house filter vs. softener vs. reverse osmosis guide.
Filtration is sold on certification logos, and the logos are worth understanding, because they are the one part of the sales pitch you can actually verify. These are the NSF/ANSI standards that come up:
Now the part that matters more than the rest of this page put together: certification under 53 and 58 is contaminant-specific. A filter certified under 53 for one contaminant is not certified for all of them. The standard number on the box tells you nothing on its own — the specific contaminant you care about has to appear on that product listing, by name. If a salesperson answers “it is NSF certified” and stops there, the question has not been answered.
One piece of older advice still circulates and is worth retiring: the standalone P473 protocol for PFAS was folded into 53 and 58. It is not a separate thing to shop for anymore.
Tell us whether you are on town water or a well and what you are seeing at the tap. Mon–Sat 7am–5pm.