Las Vegas, NV water hardness: 280 mg/L (16 grains per gallon)
The Las Vegas Valley Water District (LVVWD) gives an average total hardness of 280 ppm (parts per million), or 16 grains per gallon. The figure is in its 2026 report (2025 data). That is very hard on the USGS scale (over 180 mg/L).
Program a softener at 16 gpg, as LVVWD advises. Set the dishwasher to its highest or next-highest level.
What LVVWD's 2026 report says
Average total hardness is 280 ppm (16 gpg), from 2025 data. The report gives no range for hardness.
| Measure | Average | Where |
|---|---|---|
| Total hardness | 280 ppm (mg/L) | Report p. 4 and Summary |
| Total hardness in grains per gallon | 16 gpg | Report p. 4 and Summary |
| Calcium | 75 ppm | Summary |
| Magnesium | 24 ppm | Summary |
The report tells customers to “set your water softener based on our water hardness (280 parts per million or 16 grains per gallon).” The year before, the 2025 report (2024 data) gave 291 ppm or 17 gpg. On 2026-10-26, LVVWD's water quality FAQ page showed both figures in different answers. We use the newer report.
Where Las Vegas water comes from
About 90 percent comes from Lake Mead, fed by the Colorado River. The river's calcium and magnesium make the water hard. The other 10 percent comes from wells in the Las Vegas Valley aquifer, used mostly from April to October. LVVWD says homes in the northwest valley, or within several miles of its Charleston and Valley View offices, may get a blend of groundwater and lake water. The report gives one hardness figure for the system, not one per source. LVVWD publishes separate reports for Big Bend, Blue Diamond, Jean, Kyle Canyon and Searchlight on its reports page. Henderson and North Las Vegas run their own systems. These figures are for the Las Vegas Valley system.
What 280 mg/L means at home
How to program a softener for Las Vegas water
Enter 16 gpg as the hardness setting. If the softener asks for compensated hardness and you have iron in your water, follow the softener manual. LVVWD's summary lists iron below 0.05 ppm, so most homes on district water can use 16 gpg.
What to set the dishwasher to
Set the dishwasher to its highest or next-highest hardness level. 280 mg/L is about 15.7 °dH (280 ÷ 17.8). Keep the rinse aid filled. If your model has a salt reservoir, keep that filled too. At this hardness, both help prevent white film on glasses.
How much scale kettles, coffee makers, showers and water heaters get
Expect fast white scale on anything that heats water. Kettles and coffee makers need regular descaling. USGS notes that scale in water heaters can reduce efficiency and raise heating costs. LVVWD states that the minerals “pose NO health risk.”
Sources
- LVVWD, 2026 Water Quality Report (2025 data), page 4: https://www.lvvwd.com/assets/pdf/water-quality-report-las-vegas-valley-current.pdf
- LVVWD, 2026 Water Quality Summary (hardness, calcium, magnesium, iron): https://www.lvvwd.com/assets/pdf/water-quality-summary-las-vegas-valley.pdf
- LVVWD, 2025 Water Quality Report (2024 data, prior figure): https://www.lvvwd.com/assets/pdf/water-quality-report-las-vegas-valley-archive.pdf
- LVVWD, Water quality reports list: https://www.lvvwd.com/water-quality/reports/index.html
- USGS Water Science School, Hardness of Water: https://www.usgs.gov/water-science-school/science/hardness-water