What to set your water softener to, town by town

The short answer

Set your softener's hardness to the number your water actually has, in grains per gallon. On city water, that is the figure your utility publishes. On a private well, it is the hardness on your well's lab report. Do not rely on the factory preset. The City of Hartford Sewer Utility notes that some softeners are preset at the factory to the highest hardness setting, which may be as high as 30 grains.

Getting it right is about salt. The West Bend Sewer Utility says setting your softener for the proper hardness will save you money on salt and help protect the environment. Below is what each nearby utility tells its residents. For the bigger picture, see hard water in Wisconsin.

Where your number comes from

City water customers can usually find a hardness figure in one of three places. The water utility may post it in an FAQ, as Brookfield and Menomonee Falls do. In several towns here, the sewer utility publishes softener guidance, because softener salt ends up at the treatment plant and, as Hartford's FAQ explains, standard treatment cannot remove chloride. And Wisconsin DNR posts compliance sample results for public water systems: its record for Hartford Waterworks, for example, lists total hardness for each of the city's five active wells.

On a private well, nobody publishes your number, so a lab measures it. Waukesha County Environmental Health runs a state certified laboratory that tests well water for hardness, and encourages private well owners to test yearly or after modifying the well.

For towns not covered below, each town page under service areas gives the figure we found in the utility's or the state's published records, or says so when there is no single published figure.

Reading mg/L as grains

A softener's hardness setting is in grains per gallon, as the City of Brookfield notes. Lab reports and DNR results usually read in milligrams per liter (mg/L), and Hartford's FAQ notes that labs often record hardness as mg/L or parts per million (ppm). Both the Hartford and Town of Brookfield utilities publish the conversion: one grain per gallon equals 17.1 mg/L. So divide mg/L by 17.1.

• 390 mg/L divided by 17.1 is about 23 grains.
• 450 mg/L divided by 17.1 is about 26 grains.

Both examples are Hartford's 2026 well samples, covered below.

Brookfield and Menomonee Falls

City of Brookfield. Its water FAQ says city water averages approximately 23 to 34 grains. Its chloride reduction guidance calls the supply very hard at around 23 grains, notes that some manufacturers preset softeners at a very high hardness level, and says to adjust the hardness level down to 23 grains if necessary. Both figures are for City of Brookfield water.

Town of Brookfield. Homes on the Town's Sanitary District No. 4 water are on a separate system fed by the Town's six wells, which the district puts at typically 32 to 35 grains, or 549 to 598 mg/L. The City's figures do not apply there. Our Brookfield page covers both.

Menomonee Falls. The Village's utility FAQ lists two supplies: Milwaukee water at 7 to 9 grains and village well water at 27 to 32 grains. Find out which supply serves your address before you touch the dial. More on the Menomonee Falls page.

Waukesha, on lake water since 2023

Waukesha switched from groundwater to 100% Lake Michigan water in October 2023, according to the Waukesha Water Utility. The Great Water Alliance, the program site for the switch, put the old groundwater supply at around 21 grains per gallon and the lake water at 8. A softener still set for the old well water is set for water the city no longer delivers.

The City also has a softener rule: its softener salt program page says City Ordinance 29.08 requires all softeners to be fully optimized, and that adjusting the hardness alone does not take the place of a full optimization. Per the same page, a full optimization covers the hardness, salt dosage and reserve capacity settings, done by an approved optimizer company, and a new or replacement softener must still be optimized by one of the program's technicians for that brand. The program covers every softener that drains to the Waukesha sewer system, including those in portions of Pewaukee, Wales and the Village of Waukesha. Our Waukesha page covers the switch in more detail.

Hartford and West Bend

Hartford. The City of Hartford Sewer Utility's chloride FAQ, revised January 26, 2023, says water from the city's utility is typically 18 to 22 grains and asks residents to reset the hardness to 20 grains. Newer state data reads higher: Wisconsin DNR compliance samples taken February 9, 2026 at the city's five active wells measured 390 to 450 mg/L of total hardness, about 23 to 26 grains.

Both numbers are official, and they do not match. See the Hartford page.

West Bend. The City of West Bend Sewer Utility's 2026 newsletter, dated February 3, 2026, says the proper setting for a water softener in its service area is 25 to 31 grains of hardness. The same newsletter says the utility's sewer use ordinance and a state Department of Safety and Professional Services rule require high-efficiency, demand-initiated regeneration softeners, which track water use and regenerate only when needed. See the West Bend page.

The setting is one part of it

The other part is how your softener decides when to regenerate. Hartford's FAQ explains the difference: a timer softener regenerates after a fixed amount of time regardless of how much water is used, while a demand-initiated unit tracks water use or uses a hardness sensor, and is the more efficient of the two in salt and water. If yours is a timer unit, or old enough that nobody remembers setting it, our guide to replacing a water softener covers what to look at.

How we size it

ZeroGrain Water sells one system, the ZeroGrain One: a softener with carbon, plus a reverse osmosis drinking water tap. The quote is a free phone call of about 15 minutes, sized from your town's published hardness or your well's lab result, so have that number handy if you have one. An independent licensed Wisconsin plumbing contractor installs it and pulls any permit, and the hardness is retested at the tap as part of the install. The ZeroGrain One is $3,950 installed. How it works walks through the steps, and the FAQ covers the rest.

Published September 29, 2026. Every figure on this page links the utility, county or state page that publishes it.