> readings of PFAS that exceed EPA limits have been found in just 8% of small public water systems (those that serve fewer than 10,000 people) and 15% of large ones
15%!
Anyone who trusts their municipal water supply because of *handwave* regulations and reports needs to read that again.
Even if my water were 100% pristine as the author's apparently is, which they only know for their own homes because they've tested it at their taps half a dozen times with different laboratories, my tap water still tastes awful, and maintaining a dedicated three stage filter spout next to my kitchen faucet costs me approximately nothing and provides substantially better tasting water. And I don't need to worry about whether I live in the next Flint, Michigan.
It took two whole years for administrators in Flint, Michigan to acknowledge their lead pipe crisis. What your treatment plant claims it does and what your municipal government claims your safety profile is do not matter one bit if you aren't constantly testing the water actually coming out of your taps.
I'd rather just filter my water. It's much less hassle and I get better tasting water as a nice bonus.
I've thought about this, but I don't think so. My last two paragraphs addresses what I think are RO's risks.
First there has to be bacteria in the municipal water. The city does a pretty good job there,
Second there has to be organic matter for the bacteria to grow. Again, cities are good with that.
But even if you have bacteria in your water, a good RO system's pores should be smaller than a virus (really smaller than a prion) or it won't be able to remove metallic ions.
But let's assume after two years these assumptions fail because the filters get old. Replace the filters and flush the system with bleach.
My fear with RO are bad filters. I once had a Zero pitcher and it tasted bad, acidic. A few weeks later there was a recall that the RO membrane was leaking ionomers.
Moral of the story- trust your senses. If municipal water tastes bad, it's bad. If bottled water tastes bad, it's bad. If RO water tastes bad, it's bad.
From someone that keeps aquariums, municipal water that is stripped of it's chlorine by carbon has the ingredients to grow bacteria. They need three things, carbon, phosphate and nitrogen, all of which will be present to varying degrees. Particularly nitrates and phosphates. They're not harmful until concentrations are really high but certainly enough to grow bacteria.
Also consider what your holding tank and supply to the water, either through leaching, accumulation or simply time
RO (without DI) does not remove everything. With an advanced setup like with a booster pump and a 5:1 waste ratio and a high quality filter you would probably see a 95% reduction.
But without a booster pump or if you've got a lower waste ratio either by restriction or piggyback ro membranes you'll have a lower rejection rate.
And that ignores the fact the you really need to be back flushing the membrane regularly and rejection rates are measured after 30 minutes of continuous running, ions migrate when it's idle so you have to throw away a lot of water at the start that you're probably not doing
> Anyone who trusts their municipal water supply because of handwave regulations and reports needs to read that again.
A better approach is to decide whether your municipality meets or exceeds guidelines (the 85% that do).
I trust my city (in New Zealand), but there are other cities I wouldn’t because their water infrastructure is old and under funded, or because of known problems in the recent past.
> and maintaining a dedicated three stage filter spout next to my kitchen faucet costs me approximately nothing
Calling bullshit on this one. I have one, it's positively wonderful, but the filters are expensive and per the manufacturer's recommendation you're supposed to change them all simultaneously. So when one times out, they all time out. This runs approximately $150 a year minimum depending on usage.
People spend an order of magnitude (and much more) on coffee every day, never mind smokers or drinkers who spend crazy amounts just to hurt themselves.
Not that I don't love and respect Wirecutter (I don't), but I'm on team "I like how my water tastes when it's filtered."
Some units give you different fixed timespans for each. For that reason, I just use the Reverse Osmosis stage and ignore the rest. RO is the last step, and in theory it renders pure water meaning the only reason to have the previous ones is to pre-filter somewhat the water and extend the RO cartridge lifespan. Problem with that is, first, there's no way to gauge when each filter is spent. Second, they're priced the same anyway, so why even bother. Just go straight from tap to RO! Keep the post re-mineralization stage if you want.
pre-filters typically have specified "capacity" in gallons. which is measurable. also if water is very dirty filters get clogged and pressure dropped. it's also measurable.
"post re-mineralization stage" is actually "ph adjustment".
I know pressure drops. The problem is knowing which filter is the one causing it in particular. Also, filters that are spent at different rates are a PITA. What I mean is if you are going to feed it nominally clean tap water, there's no reason to protect a catridge with equally or more expensive cartridges. Just use the RO filter and be done with it.
you can put pressure guages in between or one of $10 flow meters before system.
RO membrane doesn't remove chlorine iirc or vocs. On the other side chlorine degrades membrane. "nominally clean tap water" can have enough dirt to clog membrane if you don't auto backflush it frequently
It isnt merely ph adjustment... You want some amount of minerals in water for your health, plants, and taste. Changing the PH isnt the concern in most cases, its just part of the result.
All those filters are specifically made for PH adjustment (you are welcome to look at specs). There are bunch of different formulations depends on how much PH adjustment is needed.
RO makes water more acidic. if water was somewhat acidic to start with, it can get more acidic or become corrosive.
Are you sure that it makes it more acidic? AFAIK it only outputs pure H20, should be neutral. If you feed it alkaline water you'll get "more acidic" water, but the other way if you feed it acidic water.
True. But have tasted distilled water? Tastes metalic. Probably just my imagination but I feel like it pulls stuff from the mucous in your mouth and tastes like blood.
What system are you using? My five stage filter system has me replace the charcoal filters once a year and the RO every... three? Maybe five?
But let's assume it costs you $150 a year. Thats less than $0.50 a day for drinking and cooking water. I doubt you could buy any significant amount of bottled water for fifty cents.
I'm failing to see your point. If you think it helps -- whether because of taste or personal trust issues or something else -- then great, filter your water. You do you.
The article is clearly for someone who is otherwise on the fence and doesn't have those issues.
That's weird because I'm pretty sure that my point is explicitly spelled out. But just in case, here it is again:
If your trust is based in municipal numbers or statements, you should be aware that municipal numbers and statements are not trustworthy because there's a lot of widespread decaying infrastructure (and coverup!) between where they test, what they make public, and where your water comes out of your faucet.
And if your trust is based on "Rah, rah, America!", you should know that 15% (!!) of water systems serving over 10k people have PFAS levels measured above what the EPA says is safe. (And if you don't think that 15% is a lot, holy smokes, that's nuts.)
So if you aren't testing your tap constantly then you have no idea what your water is like, no matter what the city says their water is like.
And if you are testing your taps constantly, it's less hassle and gives a better result to just filter your water instead.
The author says "I don't filter because I constantly test my taps and they're good each time." That's not the same at all as saying that filtering isn't a generally good idea, especially for anyone who isn't constantly testing their taps. The author ALSO says "a fuckton of you have more PFAS in your water than the EPA says is safe, just not me, lol". The author also chooses to ignore that their good water today may become bad tomorrow.
> That's weird because I'm pretty sure that my point is explicitly spelled out.
Yeah I read it the first time, so repeating it is non responsive. The article was about one person's opinion on the subject of water filters. Your opinion is just one more in a sea of opinions. It's not like the author hid those numbers that you keep repeating -- you're just (again, repeatedly) saying they're scarier than the author felt they were.
> And if your trust is based on "Rah, rah, America!", you should know that 15% (!!) of water systems serving over 10k people have PFAS levels measured above what the EPA says is safe. (And if you don't think that 15% is a lot, holy smokes, that's nuts.)
Yeah, OK. So basically you just want everyone to be as scared as you are.
I don't have a strong opinion on the matter, but your "holy smokes, that's nuts" is worth approximately what I paid to read it. That goes for the author, too, btw.
>> municipal numbers and statements are not trustworthy
The claims of the manufacturers of filters, of course, are completely trustworthy. If you aren't testing the capabilities of your filters constantly, this is fine.
I don't trust the manufacturer, but I can test the manufacturers water.
I don't trust my municipality because they cheaped out on the corrosion inhibitors chemistry, leached lead into the water and my house is now filled with developing pinhole leaks. I've had five in four years.
> readings of PFAS that exceed EPA limits have been found in just 8% of small public water systems (those that serve fewer than 10,000 people) and 15% of large ones
15%!
Anyone who trusts their municipal water supply because of *handwave* regulations and reports needs to read that again.
Even if my water were 100% pristine as the author's apparently is, which they only know for their own homes because they've tested it at their taps half a dozen times with different laboratories, my tap water still tastes awful, and maintaining a dedicated three stage filter spout next to my kitchen faucet costs me approximately nothing and provides substantially better tasting water. And I don't need to worry about whether I live in the next Flint, Michigan.
It took two whole years for administrators in Flint, Michigan to acknowledge their lead pipe crisis. What your treatment plant claims it does and what your municipal government claims your safety profile is do not matter one bit if you aren't constantly testing the water actually coming out of your taps.
I'd rather just filter my water. It's much less hassle and I get better tasting water as a nice bonus.