Charlotte, NC water hardness
Charlotte Water publishes an average hardness of 32 mg/L for its system, in its Charlotte Water 2025 Annual Drinking Water Quality Report. On the USGS scale that is soft water.
The published figure, exactly as it appears
This is the hardness line transcribed from the source, with nothing added:
Hardness, Total as CaCO3 (ppm) 2025 32 27 – 35 N/A
Charlotte Water, Charlotte Water 2025 Annual Drinking Water Quality Report
Units as published: ppm. What kind of figure it is: an average with a range. Retrieved 2026-10-17.
Charlotte 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 | 32 | 1.9 | mg/L published, gpg is our conversion |
| Low end of published range | 27 | 1.6 | mg/L published, gpg is our conversion |
| High end of published range | 35 | 2 | mg/L published, gpg is our conversion |
| Plotted on the scale above | 32 | 1.9 | 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: 32 ÷ 17.1 = 1.9 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 | Charlotte Water |
|---|---|
| Public water system ID | 01-60-010 |
| Service area as published | Charlotte Water's system, water system number 01-60-010. The row is sampled at the entry point to the distribution system rather than at customer taps. |
Provenance of every number on this page
| Source document | Charlotte Water 2025 Annual Drinking Water Quality Report |
|---|---|
| Source URL | https://www.charlottenc.gov/files/sharedassets/cltwater/v/3/documents/water-quality/ccr/current-consumer-confidence-report.pdf |
| Published by | Charlotte Water |
| Report year | 2025 |
| Year note | The hardness row is in the report's “Other Miscellaneous Water Characteristics” table, sampled at the entry point to the distribution system, and carries the year 2025 in its own column. |
| Retrieved | 2026-10-17 |
| Classification bands | USGS Water Science School, retrieved 2026-10-16 |
Notes the report forces on this page
- The figure is measured at the entry point to the distribution system, not at customer taps.
- The report publishes no grains-per-gallon figure; every grains figure on this page is our conversion at 17.1 mg/L per grain.
- The “N/A” at the end of the row is the secondary-MCL column, which the report leaves unset for hardness.
If you are sizing a softener for Charlotte water
At 1.9 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 Charlotte 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
- New York, NY New York City Department of Environmental Protection (NYC DEP), 32 mg/L (1.9 gpg)
- Raleigh, NC Raleigh Water, 25 mg/L (1.5 gpg)
- Memphis, TN Memphis Light, Gas and Water, 46 mg/L (2.7 gpg)
- Manchester, NH Manchester Water Works, 17.9 mg/L (1 gpg)
All 44 verified systems How to find hardness in your own utility's report If you are on a well instead