Water hardness in Nevada
Nevada has a median ambient water hardness of 133 mg/L, which is 7.8 grains per gallon and classes as hard. That is the middle of 24,625 samples across 17 counties.
This is ambient water, not tap water. These figures come from samples taken from wells, streams and springs by USGS, EPA and state agencies. Municipal utilities treat, blend and sometimes soften water before it reaches a tap, so a city supply can be considerably softer than the ground beneath it. Treat this as a good guide for a private well and an approximate one for city water. Your utility's annual water quality report gives the real number for a municipal tap, and a test strip gives it for yours.
Every monitored county in Nevada
Ranked hardest first. The middle 50% column shows how much the samples within a county vary, which matters more than the median where a county spans two geologies.
| County | mg/L | gpg | Class | Middle 50% | Samples |
|---|---|---|---|---|---|
| Mineral County | 609 | 35.6 | Very hard | 120 to 697 | 1,329 |
| Clark County | 340 | 19.9 | Very hard | 320 to 415 | 4,380 |
| Eureka County | 187 | 10.9 | Very hard | 150 to 226 | 525 |
| Lander County | 187 | 10.9 | Very hard | 140 to 229 | 240 |
| Lincoln County | 185 | 10.8 | Very hard | 124 to 227 | 252 |
| Pershing County | 182 | 10.6 | Very hard | 168 to 210 | 984 |
| White Pine County | 168 | 9.8 | Hard | 41 to 190 | 1,011 |
| Storey County | 106 | 6.2 | Moderately hard | 61 to 166 | 153 |
| Elko County | 102 | 6 | Moderately hard | 5 to 168 | 2,398 |
| Lyon County | 102 | 6 | Moderately hard | 76 to 141 | 1,693 |
| Churchill County | 96 | 5.6 | Moderately hard | 38 to 216 | 1,743 |
| Humboldt County | 95 | 5.5 | Moderately hard | 27 to 135 | 824 |
| Douglas County | 80 | 4.7 | Moderately hard | 47 to 127 | 2,503 |
| Carson City | 78 | 4.6 | Moderately hard | 42 to 130 | 664 |
| Washoe County | 65 | 3.8 | Moderately hard | 35 to 132 | 4,534 |
| Nye County | 51 | 3 | Soft | 15 to 187 | 1,251 |
| Esmeralda County | 21 | 1.2 | Soft | 18 to 23 | 141 |
Source: Water Quality Portal (USGS, EPA and state agencies), waterqualitydata.us, retrieved 2026-09-19. 2,904,346 samples across 3,110 counties.
What this means for a household in Nevada
At 7.8 grains per gallon, a family of four would need a softener of about 24,000 grains to regenerate roughly weekly, using around 317 lb of salt a year. Size it for your own household.
17 of these counties include well samples, so the figures are a reasonable guide for private well water there. Municipal supplies in the same counties may be softer, because utilities often blend or treat.
Hardness follows geology rather than borders. Where a county sits on limestone or dolomite the water is hard; on granite, basalt or sandstone it is soft. That is why neighbouring counties in this table can differ by a factor of several.