Salt Lake City, UT water hardness
Salt Lake City Department of Public Utilities does not publish one hardness figure for Salt Lake City. It publishes 7 separate figures, one per source, in its Salt Lake City Public Utilities 2026 Water Quality Report (2025 data). Across them the published numbers run from 136 to 571 mg/L. On the USGS scale those figures are not all in one class: they span hard and very hard water, so which class describes an address depends on which source serves it. Every published figure is in the table below.
Every figure Salt Lake City Department of Public Utilities publishes, by source
These are the only hardness numbers this utility publishes. There is no system-wide figure to quote, so the figure plotted above is a midpoint we calculated from the lowest and highest of them, and it is labelled as such everywhere it appears.
| Source as published | mg/L (ppm) | Grains per gallon | USGS class |
|---|---|---|---|
| Big Cottonwood WTP | 136 | 8 | Hard |
| City Creek WTP | 212 | 12.4 | Very hard |
| Parleys WTP | 175 | 10.2 | Hard |
| Salt Lake City wells & springs Published as a range across the city's wells and springs. | 154–571 | 9.6–33.4 | Very hard at the high end, hard at the low end |
| MWDSLS Little Cottonwood WTP (purchased) No grains/gallon figure published. | 152 | 8.9 | Hard |
| MWDSLS Point of the Mountain WTP (purchased) No grains/gallon figure published. | 164 | 9.6 | Hard |
| Jordan Valley Water Conservancy District (purchased) No grains/gallon figure published. | 184.1 | 10.8 | Very hard |
Figures in the grains column are the utility's own where it published them. Where it published only one unit, the other column is our conversion at 17.1 mg/L per grain, and the row above says which. Nothing in this table is averaged across sources.
The published figures, exactly as they appear
This is the hardness line transcribed from the source, with nothing added:
Hardness, Total UR ppm NE 136 212 175 154 - 571 152 164 184.1; grains / gallon Calculated NE 8.0 12.4 10.2 9.6 - 33.4 - - - (columns: Big Cottonwood WTP, City Creek WTP, Parleys WTP, Range of Salt Lake City Wells & Springs, MWDSLS Little Cottonwood WTP, MWDSLS Point of the Mountain WTP, Jordan Valley Water Conservancy District (JVWCD))
Salt Lake City Department of Public Utilities, Salt Lake City Public Utilities 2026 Water Quality Report (2025 data)
Units as published: ppm, with a calculated grains/gallon row for city-operated sources. What kind of figure it is: figures for each source, with no system-wide figure. Retrieved 2026-10-26.
Salt Lake City hardness in mg/L and grains per gallon
Water-quality reports use mg/L (identical to ppm). Softener instructions and plumbing specifications use grains per gallon. Both are below. Where a figure is our arithmetic rather than the utility's own number, it says so.
| Figure | mg/L (ppm) | Grains per gallon | Whose number |
|---|---|---|---|
| Low end of published span across areas | 136 | 8 | both published by the utility |
| High end of published span across areas | 571 | 33.4 | both published by the utility |
| Plotted on the scale above | 353.5 | 20.7 | midpoint of the lowest and highest figures published across this system's 7 areas; the utility publishes no system-wide figure, so this midpoint is not one of its numbers; the gpg here is our conversion at 17.1, so it can differ slightly from a utility’s own rounded gpg figure |
The conversion, both ways: gpg = mg/L ÷ 17.1 and mg/L = gpg × 17.1. Worked for this system: 353.5 ÷ 17.1 = 20.7 gpg. The converter does °dH and °f as well, and why the factor is 17.1 explains where the number comes from.
What this figure does not tell you
Service area and source water
| Utility | Salt Lake City Department of Public Utilities |
|---|---|
| Service area as published | Salt Lake City and the other communities in SLCDPU's service area. The report does not say which addresses each source serves. |
| Source water | Mountain streams treated at Big Cottonwood, City Creek and Parleys plants; city wells and springs; and water purchased from the Metropolitan Water District of Salt Lake & Sandy (Little Cottonwood and Point of the Mountain plants) and the Jordan Valley Water Conservancy District. |
Provenance of every number on this page
| Source document | Salt Lake City Public Utilities 2026 Water Quality Report (2025 data) |
|---|---|
| Source URL | https://www.slc.gov/utilities/wp-content/uploads/sites/22/2026/06/2026-04_Water-Quality-Report-2026-digital-FNL.pdf |
| Published by | Salt Lake City Department of Public Utilities |
| Report year | 2025 |
| Year note | The report's tables list contaminants detected during the calendar year of the report, stated as 2025 data. |
| Retrieved | 2026-10-26 |
| Classification bands | USGS Water Science School, retrieved 2026-10-16 |
Notes the report forces on this page
- Salt Lake City publishes one figure per source and no system-wide figure. Single-number columns are shown in the average column; the report does not say whether each is an average or a single result.
- The utility's own two units do not agree at the low end of the wells and springs range: 154 ppm is about 9.0 grains per gallon at 17.1, but the report prints 9.6. The other calculated values (8.0, 12.4, 10.2 and 33.4) match their ppm figures at 17.1. Both are reproduced as published.
- The sources span the USGS hard and very hard bands, and the wells and springs range alone runs from hard to very hard. The plotted point is the midpoint of the lowest and highest published figures across the sources; it is not a figure the utility published.
- The 2024 report's columns did not render legibly to this site's text reader on 2026-10-17; the 2026 report (2025 data) was read as rendered pages on 2026-10-26 with every column heading visible.
If you are sizing a softener for Salt Lake City water
At 20.7 gpg, the sizing arithmetic starts from your household's water use, not from the hardness alone. The calculator below is pre-filled with this system's figure and every other input is an editable assumption.
Whether a softener is worth installing at this hardness is a judgement, not arithmetic, and it is not one this site makes for you. Nothing here has been tested by the author.
Where Salt Lake City sits against other verified systems
- Portland, OR 9 mg/L 0.5 gpg Soft
- Boston, MA 16 mg/L 1 gpg Soft
- Manchester, NH 17.9 mg/L 1 gpg Soft
- Seattle, WA 19.1 mg/L 1.1 gpg Soft
- Raleigh, NC 25 mg/L 1.47 gpg Soft
- New York, NY 32 mg/L 2 gpg Soft
- Charlotte, NC 32 mg/L 1.9 gpg Soft
- Memphis, TN 46 mg/L 2.7 gpg Soft
- Norfolk, VA 48 mg/L 2.8 gpg Soft
- Anchorage, AK 56 mg/L 3.3 gpg Soft
- Virginia Beach, VA 56 mg/L 3.3 gpg Soft
- Oakland, CA 68.4 mg/L 4 gpg Moderately hard
- Nashville, TN 77.3 mg/L 4.5 gpg Moderately hard
- Sacramento, CA 83 mg/L 4.9 gpg Moderately hard
- Fresno, CA 89.3 mg/L 5.2 gpg Moderately hard
- Saint Paul, MN 90 mg/L 5 gpg Moderately hard
- Austin, TX 93 mg/L 5.4 gpg Moderately hard
- Minneapolis, MN 94 mg/L 5.5 gpg Moderately hard
- Washington, DC 95 mg/L 5.6 gpg Moderately hard
- Baltimore, MD 97.5 mg/L 5.7 gpg Moderately hard
- Birmingham, AL 98 mg/L 5.7 gpg Moderately hard
- Kansas City, MO 100 mg/L 5.8 gpg Moderately hard
- Denver, CO 105 mg/L 6.1 gpg Moderately hard
- Detroit, MI 107 mg/L 6.3 gpg Moderately hard
- Aurora, CO 113 mg/L 6.6 gpg Moderately hard
- Tulsa, OK 114.5 mg/L 6.7 gpg Moderately hard
- Louisville, KY 115 mg/L 6.7 gpg Moderately hard
- Columbus, OH 120 mg/L 7 gpg Moderately hard
- Cleveland, OH 120 mg/L 7 gpg Moderately hard
- Philadelphia, PA 125 mg/L 7.3 gpg Hard
- Ann Arbor, MI 126 mg/L 7.4 gpg Hard
- Cincinnati, OH 133 mg/L 7.8 gpg Hard
- Chicago, IL 134.5 mg/L 7.9 gpg Hard
- Houston, TX 135.5 mg/L 7.9 gpg Hard
- Milwaukee, WI 137 mg/L 8.01 gpg Hard
- St. Louis, MO 138 mg/L 8.1 gpg Hard
- Grand Rapids, MI 142 mg/L 8.3 gpg Hard
- Fort Worth, TX 145 mg/L 8.5 gpg Hard
- Spokane, WA 159 mg/L 9.3 gpg Hard
- Honolulu, HI 162.5 mg/L 9.5 gpg Hard
- Wichita, KS 170 mg/L 9.9 gpg Hard
- Omaha, NE 170 mg/L 10 gpg Hard
- Los Angeles, CA 192 mg/L 11.2 gpg Very hard
- Lincoln, NE 192 mg/L 11.2 gpg Very hard
- Riverside, CA 197 mg/L 12 gpg Very hard
- Tampa, FL 220 mg/L 12.9 gpg Very hard
- Phoenix, AZ 237 mg/L 13.9 gpg Very hard
- Mesa, AZ 239.4 mg/L 14 gpg Very hard
- Round Rock, TX 258 mg/L 15.1 gpg Very hard
- Pflugerville, TX 267 mg/L 15.6 gpg Very hard
- San Diego, CA 276 mg/L 16 gpg Very hard
- Las Vegas, NV 280 mg/L 16 gpg Very hard
- Chandler, AZ 282.2 mg/L 16.5 gpg Very hard
- San Antonio, TX 299.3 mg/L 17.5 gpg Very hard
- Anaheim, CA 300 mg/L 18 gpg Very hard
- Henderson, NV 304 mg/L 18 gpg Very hard
- Indianapolis, IN 317 mg/L 19 gpg Very hard
- Madison, WI 324.9 mg/L 19 gpg Very hard
- Scottsdale, AZ 352.5 mg/L 20.6 gpg Very hard
- Salt Lake City, UT 353.5 mg/L 20.7 gpg Very hard
mg/L as calcium carbonate. Each classification band is drawn the same width, so the axis is not linear in mg/L.
Systems with similar published hardness
- Scottsdale, AZ Scottsdale Water, 352.5 mg/L (20.6 gpg)
- Madison, WI Madison Water Utility, 324.9 mg/L (19 gpg)
- Indianapolis, IN Citizens Energy Group (Indianapolis), 317 mg/L (18.5 gpg)
- Henderson, NV City of Henderson Department of Utility Services, 304 mg/L (17.8 gpg)
All 60 verified systems How to find hardness in your own utility's report If you are on a well instead