Cleveland, OH water hardness
Cleveland Water publishes a hardness of 120 mg/L (7 grains per gallon, also its own figure) for its system, in its Cleveland Water, “What is Hard Water and Should You Worry About It?”, published 9 March 2022. On the USGS scale that is moderately hard water.
The published figure, exactly as it appears
This is the hardness line transcribed from the source, with nothing added:
Specifically, the hardness of Cleveland Water is 7 grains/gallon or 120 mg/L (milligrams per liter) as calcium carbonate and is based on the naturally occurring level of minerals in Lake Erie.
Cleveland Water, Cleveland Water, “What is Hard Water and Should You Worry About It?”, published 9 March 2022
Units as published: grains/gallon, with mg/L as calcium carbonate given alongside. What kind of figure it is: a single value. Retrieved 2026-10-17.
Cleveland 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 |
|---|---|---|---|
| Published average | 120 | 7 | both published by the utility |
| Plotted on the scale above | 120 | 7 | published average; 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: 120 ÷ 17.1 = 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 | Cleveland Water |
|---|---|
| Service area as published | Cleveland Water's service area. The article does not break the figure down by treatment plant. |
| Source water | Lake Erie, per the article, which attributes the hardness to the naturally occurring level of minerals in the lake. |
Provenance of every number on this page
| Source document | Cleveland Water, “What is Hard Water and Should You Worry About It?”, published 9 March 2022 |
|---|---|
| Source URL | https://www.clevelandwater.com/who-we-are/news/what-hard-water-and-should-you-worry-about-it |
| Published by | Cleveland Water |
| Report year | 2022 |
| Year note | The article is dated 9 March 2022. It is not an annual report and states no sampling year for the figure. |
| Retrieved | 2026-10-17 |
| Classification bands | USGS Water Science School, retrieved 2026-10-16 |
Notes the report forces on this page
- Cleveland Water publishes one figure here and no sampling range.
- The article describes the water as moderately hard on the ASABE and WQA classification scale. The classification shown on this page is the USGS one, which also places 120 mg/L in its moderately hard band.
- The article is dated 9 March 2022 and is not an annual report, so the figure is not tied to a sampling period.
If you are sizing a softener for Cleveland water
At 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 Cleveland 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
- 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
- Anchorage, AK 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
- Washington, DC 95 mg/L 5.6 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
- 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
- Milwaukee, WI 137 mg/L 8.01 gpg Hard
- St. Louis, MO 138 mg/L 8.1 gpg Hard
- Fort Worth, TX 145 mg/L 8.5 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
- 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
- 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
- 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
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
- Columbus, OH City of Columbus Division of Water, 120 mg/L (7 gpg)
- Philadelphia, PA Philadelphia Water Department, 125 mg/L (7.3 gpg)
- Louisville, KY Louisville Water Company, 115 mg/L (6.7 gpg)
- Tulsa, OK City of Tulsa Water and Sewer, 114.5 mg/L (6.7 gpg)
All 44 verified systems How to find hardness in your own utility's report If you are on a well instead