This page is going to talk you out of the thing we sell. A hardness reading in the teens or twenties of grains comes with an obvious recommendation attached. Mason City's published reading is 5.1 grains, and the honest recommendation for most homes on city water is: do not buy a softener. What follows is why that is true, where the number comes from, and what is genuinely worth installing here instead.
| Mason City at a glance | What the record shows |
|---|---|
| Who supplies the water | Mason City Water Department, PWSID IA1750048, serving 27,338 people in EPA SDWIS; the Iowa DNR sanitary survey of 31 October 2017 records 28,079 and average demand of 4.232 million gallons a day |
| Where it comes from | Nine Jordan aquifer wells between 1,200 and 1,538 feet deep, all logged Cambrian-Ordovician in the Iowa DNR Source Water Protection Tracker, blended before treatment |
| Softened at the plant | Partly, and by accident. There is no softening unit process and no softening objective anywhere in the federal treatment record. Calcium comes out as a by-product of an electrodialysis reversal plant built for radium |
| Published hardness | 87 mg/L as calcium carbonate, about 5.1 grains per gallon, in treated water sampled 7 March 2012 — the only hardness result the Iowa DNR sample database holds for this system, ever |
Mason City draws deep Jordan sandstone water, and deep Jordan water in north central Iowa carries naturally occurring radium. The city's answer, at Plant #5 on 13th Street NE, is electrodialysis reversal — EDR. An electric current pulls dissolved minerals across ion-selective membranes into a waste stream, and the polarity flips on a cycle to keep the membranes from fouling.
The Iowa DNR's own inspector describes the installation as “4 banks of 24 stack, 3 stage Electrodialysis Reversal (EDR) treatment units for radium treatment” in the sanitary survey dated 31 October 2017. The stated purpose is radium. Nobody at the plant set out to soften anything.
But EDR is not selective. It does not know a radium ion from a calcium ion, and the same survey records what that costs the city: “Polymer addition (Hypersperse MDC704 antiscalant) is used to keep removed calcium hardness in suspension in the wastewater stream from the facility.” That is the state regulator writing the phrase removed calcium hardness. The plant strips out so much calcium that it has to dose a scale inhibitor to stop that calcium from cementing up its own reject line. The identical paragraph appears word for word in the previous survey, dated 14 July 2015, so this is the settled configuration and not a one-off note.
Radium removal is the utility's job, done at the plant, upstream of every house in the city. It is not a job we ask a home system to do and we do not sell equipment on that basis. What matters to you is the side effect: the water reaching your meter has had most of its calcium taken out of it on the way to somewhere else.
87 mg/L as calcium carbonate. Divide by 17.1 and you get 5.1 grains per gallon. That sits inside the USGS “moderately hard” band of 61 to 120 mg/L — below “hard” at 121 to 180, and a long way below “very hard” above 180, which is the band a great deal of Iowa groundwater falls into.
Now the caveat, because it is not a small one. That result was collected on 7 March 2012, at a plant tap labelled SPECIAL - TREATED, and it is the only hardness figure in the Iowa DNR sample database for PWSID IA1750048. We swept every analyte the portal carries across 1990 to 2026; analyte 84 returns exactly one row. There is no published raw well hardness for Mason City at all, so nobody can honestly quote you a before-and-after spread, and the one finished number is thirteen years old. We would rather measure your kitchen tap than defend a 2012 sample.
Three other measurements from the same record point the same direction and make the 87 easier to believe. Sulfate in four raw wellhead samples taken 16 May 1994 ran 53 to 79 mg/L; finished sulfate in 2012 was 9 mg/L, roughly an 86 percent reduction. Raw conductivity across four wellheads in 2001 sat between 750 and 800 micromho per centimetre, while finished total dissolved solids measured 145 mg/L. And sodium at the treated entry point was 25.2 mg/L on 18 March 2025, inside a 25 to 32 mg/L band that has held since 2005 — well inside the raw wellhead range of 23 to 39 mg/L in samples from 1994, 2002 and 2003.
That sodium figure settles it for anyone who suspects the city is quietly running a softener. Ion exchange trades hardness for sodium; a whole-plant softener on this water would have pushed treated sodium far above anything in the record. It did not move. Treatment here removes minerals rather than swapping them, which matters to a household watching salt intake.
Third-party hardness tables that print a figure for Mason City are not quoting the Iowa DNR record, because the DNR record holds exactly one hardness result for this system and it reads 87 mg/L. A figure quoted without that value and that date did not come out of Iowa's sample database.
The federal record is equally easy to misread in the other direction. EPA SDWIS holds thirteen treatment rows for Mason City, and not one of them carries a softening objective — the codes present are disinfection, filtration, particulate control, radionuclide and other. Read that alone and you would write “Mason City does not soften.” Read the state's inspection report and calcium is coming out anyway. Both halves are needed, which is why we hold this town at partial, and why our Iowa water hardness by city guide lists Mason City with its date and caveat rather than a tidy number.
The Source Water Protection Tracker lists eleven Mason City wells; nine are active and every one of them is a Jordan aquifer well between 1,200 and 1,538 feet. The drilling dates read like a municipal history: Well #7 in 1910, Well #8 in 1912, Well #9 in 1913, Well #10 in 1932, Well #A3 in 1933, Well #12 in 1947, Wells #14 and #A1 in 1957, and Well #16, the newest, in 1989. Wells #6 and #11 are logged as not used, and Well A2 was abandoned and plugged. Individual depths disagree by up to a hundred feet between the tracker and the survey, so we quote the range rather than any single well.
All nine alternate into service by demand and mix freely before treatment, so there is a single entry point to distribution and a single water chemistry citywide. Whether you live near the Federal Avenue tower, off Kentucky Avenue or south by Georgia Hanford Park, you are drinking the same blend. Storage behind it comes to roughly eight million gallons: a four million gallon ground reservoir across the street from the plant, a half million gallon in-plant clear well, and five elevated tanks.
The federal facility list also carries a fingerprint of a rebuild. Plants #1, #2, #3 and #4 were all deactivated on the same day, 10 June 2004, along with four separate wellhead sampling stations, leaving Plant #5 as the only active plant. The records never state when Plant #5 was built, so treat this as inference — but it reads like a city that retired four scattered wellhead sites for one central plant. The first treated sample from the current entry point is dated April 2005.
At about five grains, most Mason City homes on city water will not see the scale film, the soap curd and the shortened water heater life that drive softener purchases in harder-water Iowa towns. So we lead with the drinking water instead. Every price is all-in: equipment, installation by a licensed local plumbing professional, taxes and a lifetime parts warranty.
Annual maintenance is $199 a year for a tank-RO home and $249 for a tankless-RO home. A full diagnostic service call is $199; a known-issue trip is $99 plus the part. We offer 0% financing, and $100 off for military and first responders. Ask for the written breakdown before you schedule, or start one through our instant quote.
Two details from the treatment train explain the recommendation. Mason City runs upflow forced-draft aeration specifically for hydrogen sulfide removal, so the raw Jordan water carries a sulfur note the city strips before it reaches you. And the plant makes its own disinfectant, generating sodium hypochlorite on site from salt and caustic soda, then adds fluoride as fluorosilicic acid.
What reverse osmosis does at the kitchen sink is cut the 145 mg/L of dissolved solids and the chlorine taste in the glass, the ice and the coffee. That is a taste-and-clarity argument, not a safety argument, and we will not dress it up as one. At $800 installed it is the upgrade we would spend the money on first in a Mason City household.
Everything above applies to the city's mains. Step outside them and none of it holds. A private well on an acreage near Clear Lake, Rockwell, Plymouth or Nora Springs gets no EDR, no aeration, no chlorination and no monitoring — and it is usually far shallower than the city's 1,200-foot Jordan wells, drawing from formations that are both harder and more exposed to what happens on the surface. Rural Cerro Gordo wells are not monitored and Iowa publishes no hardness data for them at all, so the only way to know what a well outside the city reads is to test it — iron and sulfur commonly show up alongside hardness on Iowa acreages.
The Iowa DNR recommends testing a private well every year, and Iowa's Private Well Grants program funds free testing through your county public health office — bacteria, nitrate and more, at no cost to the homeowner. Do that first. Our well water setup is a dual-tank system at $3,450, or $3,800 with tank RO, with 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. Start 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 and all-in, so the figure you read here is the figure on the paperwork. Distance and site conditions are the only things that can change it, and we tell you before you agree.
We will come out and measure, and we will tell you if the answer is nothing. On the evidence above that is the likely outcome for a house on city water. If you are on a well outside the city, have an old softener you want assessed, or simply want to know what your own tap reads now rather than in 2012, we will bring the kit to you. Call or text 319-319-6566, email ryan@kindwaterco.com, or book your free in-home water test.
No, not by Iowa standards. The only hardness result Iowa has ever published for the Mason City system is 87 mg/L as calcium carbonate — about 5.1 grains per gallon — in treated water sampled on 7 March 2012. That falls in the USGS moderately hard band of 61 to 120 mg/L, well below the very hard band that starts at 180 mg/L. Third-party hardness tables that print a figure for Mason City are not quoting the Iowa DNR record, which holds exactly one hardness result for this system.
Not deliberately, but calcium does come out. There is no softening unit process and no softening objective in the federal treatment record. What the city runs is electrodialysis reversal — described in the Iowa DNR sanitary survey of 31 October 2017 as “4 banks of 24 stack, 3 stage Electrodialysis Reversal (EDR) treatment units for radium treatment.” The same survey notes an antiscalant is dosed “to keep removed calcium hardness in suspension in the wastewater stream,” which is the state's own confirmation that calcium is being pulled out as a by-product.
Most homes on Mason City city water do not. At roughly five grains you are unlikely to see the scale, soap curd and shortened appliance life that make a softener worth $2,500 elsewhere in Iowa. Two exceptions: homes on private wells outside the city limits, which get none of the calcium removal the plant does, so the city's 87 mg/L tells you nothing about a well, and any house where a test at the tap reads higher than the city's published figure. We will test yours free and tell you if the answer is no.
Deep. The Iowa DNR Source Water Protection Tracker lists nine active wells between 1,200 and 1,538 feet, all drawing the Cambrian-Ordovician Jordan aquifer, drilled between 1910 and 1989. They alternate into service by demand and blend before treatment, so there is one entry point and one water chemistry across the whole city. Individual depths disagree between the tracker and the sanitary survey by up to a hundred feet, so the range is the honest figure.
Very little added by treatment. Sodium at the treated entry point measured 25.2 mg/L on 18 March 2025 and has stayed between 25 and 32 mg/L since 2005 — well inside the raw wellhead range of 23 to 39 mg/L in samples from 1994, 2002 and 2003. Ion exchange softening trades hardness for sodium and would have pushed that figure far higher, so the flat sodium record is itself evidence that no municipal softener is running.
Every figure on this page comes from a federal or Iowa state record for PWSID IA1750048, and the treatment description comes from the Iowa DNR's own inspection of the plant.
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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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