Winterset runs a reverse osmosis plant, and it has nothing to do with hardness. The city's own report states an RO system was added in January 2008 specifically to remove nitrate from the Cedar Lake supply — a candid admission that the raw reservoir water needed membrane treatment to stay compliant. Softening is not part of the job, and the city does nothing about it.
| Winterset at a glance | What the record shows |
|---|---|
| Who supplies the water | Winterset Municipal Waterworks, PWSID IA6171029, 5,428 people served (EPA SDWIS); 2024 Census city estimate 5,421 |
| Where it comes from | The Cedar Lake surface supply, treated at the city's own plant |
| Softened at the plant | No. EPA SDWIS lists twenty-two records including reverse osmosis and membrane filtration — but coded to the inorganics objective for nitrate removal, not to softening. The rest is chloramines, chlorine dioxide, granular activated carbon, permanganate, caustic soda pH adjustment and polymer coagulation |
| Published hardness | None. No total-hardness result exists for this system in the Iowa DNR sample database. Sodium at the finished-water plant tap measured 23 mg/L on 04/15/2025 |
This is the detail almost nobody outside a water plant would catch, and it changes what a homeowner should expect. Winterset's SDWIS records genuinely list reverse osmosis and membrane filtration — which at a glance looks like the kind of membrane softening that the Saylorville plant uses in the Des Moines metro. But the records are coded to the inorganics objective, and the city's report is explicit that the system was installed in January 2008 to remove nitrate.
Membranes do remove dissolved minerals, so a plant treating its entire flow by RO would soften as a side effect. Winterset's does not treat the entire flow that way — the RO is a compliance step for nitrate, and the rest of the treatment train is coagulation, filtration, carbon and disinfection. No softening objective appears anywhere. So a Winterset household should not assume the city's membranes are doing anything about hardness.
There is no hardness figure for Winterset in the state sample database and none in the city's own materials, so we will not put a number on this page. Madison County is a strong commuter shed for Des Moines with good housing values and a lot of homes bought by people who moved out from the metro — where, in most suburbs, the utility already softens. Arriving in Winterset means arriving somewhere the utility does not, and the difference tends to show up in the first month of laundry and shower doors rather than in any document.
Our Iowa water hardness by city guide shows how many Iowa towns publish nothing at all. Winterset is one of them, and the free test exists precisely for that gap.
Cedar Lake is a surface supply, and surface supplies in row-crop counties are the ones that see nitrate move with the seasons — which is precisely why Winterset built its membrane step in 2008 rather than earlier or later. Reservoirs concentrate what the watershed delivers, and spring runoff is when that shows.
Reading it that way makes the city's decision look like what it was: a specific, expensive fix for a specific compliance problem, adopted because the alternative was not meeting a standard. It also explains why the RO sits where it does in the process rather than treating everything — a plant only membranes as much flow as the compliance job requires, because membranes are costly to run.
For a household the practical read is simple. The city is managing nitrate. Nobody is managing hardness, and no one publishes what it is. Those are two separate questions and only the second one is yours to answer.
Every price is all-in: equipment, installation, taxes and a lifetime parts warranty.
Annual maintenance is $199 a year for a tank-RO home and $249 for a tankless-RO home. Diagnostic service calls are $199; a known-issue trip is $99 plus the part. We offer 0% financing, and military and first responders take $100 off. Ask for the written breakdown before booking, or start one through our instant quote.
Beyond the Winterset service area, rural Madison County homes are on private wells with no coagulation, no membranes and no disinfection behind them — and, unlike the city, no nitrate treatment either. Our well water setup is a dual-tank system at $3,450, or $3,800 with tank RO, plus UV disinfection at $700 and sediment pre-filtration at $500 when the readings call for them. We fit tank RO rather than tankless on a well, because high dissolved solids cost a tankless unit its pressure. Begin with free well water testing.
We are licensed and insured, and our softeners are built from NSF/ANSI 44 certified components and our reverse osmosis systems are certified to NSF/ANSI 58. Installation is handled by licensed local plumbing professionals we vet, schedule and stand behind. Pricing is published, all-in and identical for every household, and we would rather test your water than quote from an average.
Winterset publishes no hardness number, and the reverse osmosis in the city's plant is not there for hardness. That leaves a reading at your own tap as the only real answer. We come to you, measure hardness, iron and the rest at your kitchen sink, and hand over the numbers and a written quote before you decide anything, at no charge. Book your free in-home water test.
No. EPA SDWIS lists twenty-two treatment records for Winterset Municipal Waterworks, and although reverse osmosis and membrane filtration appear among them, they are coded to the inorganics objective for nitrate removal rather than to softening. No softening objective appears anywhere in the system's record.
The city's report states a reverse osmosis system was added in January 2008 specifically to remove nitrate from the Cedar Lake supply. It is a compliance step for nitrate, not a softening process, and it does not treat the entire flow. The rest of the treatment train is coagulation, filtration, carbon and disinfection.
No figure is published. The Iowa DNR sample database holds no total-hardness result for PWSID IA6171029, and the city publishes none of its own. Because the city's membranes are there for nitrate rather than minerals, there is no basis for assuming the water arrives softened. A free in-home test measures your own tap.
Quite possibly. Most Des Moines metro utilities soften before the water reaches homes; Winterset does not. Households moving out from the metro often notice the change first in laundry and on shower doors. Sodium at the Winterset finished-water plant tap measured 23 mg/L on 15 April 2025.
A Kind Water Co softener is $2,500 all-in, including equipment, installation, taxes and a lifetime parts warranty, or $2,850 paired with reverse osmosis. The XL build is $2,800, or $3,150 with RO. Softeners use NSF/ANSI 44 certified components and RO systems are certified to NSF/ANSI 58, with 0% financing and $100 off for military and first responders.
Every number on this page comes from a public record. Here is where to open each one yourself.
Whole-home water softening, filtration, and reverse-osmosis drinking water — professionally installed and built to last a lifetime.
Serving Marion, Cedar Rapids & surrounding Linn County communities
Kind Water Co is a d/b/a of Zero Cap Investments LLC · 2258 Bison St, Apt B, Marion, IA 52302
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