San Juan County, UT
These figures come from wells tested in San Juan County, UT, not from any one well.
- Iron is common in wells in San Juan County, UT (4 of 26 tested wells were over that level), so it's worth testing for.
- Sulfate is common in wells in San Juan County, UT (88 of 221 tested wells were over that level), so it's worth testing for.
- Manganese is not common in wells in San Juan County, UT (1 of 24 tested wells were over). Only a test tells you about your own well.
- Wells in San Juan County, UT are typically hard (220 wells tested).
- Only a test of your own well tells you about your water.
What to test for
Start with the four this site covers:
- iron (common in wells here)
- sulfate (common in wells here)
- manganese
- hardness
Most well owners also test for these. We point to the source and don't interpret the results.
- arsenic: occurs naturally in groundwater in many regions. USGS: arsenic and drinking water
- nitrate: common near farmland and septic systems. EPA: private drinking water wells
- total coliform bacteria: the standard yearly well check. EPA: private drinking water wells
- lead and copper: from household plumbing, especially when pH is below 6.5. EPA: lead in drinking water
- PFAS: several states run private-well sampling programs. EPA: PFAS
- a certified lab: states certify labs and some run their own private-well programs. Utah's certified-lab list (from your state drinking-water program)
The numbers
County figures describe the wells sampled there, not any one well. Exact counts, sample years and sources are below.
Iron Recent
| Level it's compared with | 0.3 mg/L |
|---|---|
| Share of wells over the level | 15% |
| Wells over the level / wells judged | 4 of 26 |
| Median | 0.0147 mg/L |
| Years sampled | 1950–2022 |
| Wells | 28 |
| Test results | 296 |
| Wells left out | 46 |
| Sources | USGS (145), UTAHDWQ_WQX (4), UTAHGS (2) |
Manganese Recent
| Level it's compared with | 0.05 mg/L |
|---|---|
| Share of wells over the level | 4.2% |
| Wells over the level / wells judged | 1 of 24 |
| Median | 0.007695 mg/L |
| Years sampled | 1950–2022 |
| Wells | 25 |
| Test results | 215 |
| Wells left out | 46 |
| Sources | USGS (102), UTAHDWQ_WQX (4), UTAHGS (2) |
Hardness Recent
| Level it's compared with | none; hardness is shown in bands |
|---|---|
| Share of wells very hard | 50% |
| Median | 176.5 mg/L as CaCO₃ |
| Years sampled | 1933–2022 |
| Wells | 220 |
| Test results | 457 |
| Wells left out | 46 |
| Sources | USGS (210), UTAHGS (6), UTAHDWQ_WQX (4) |
Sulfate Recent
| Level it's compared with | 250 mg/L |
|---|---|
| Share of wells over the level | 40% |
| Wells over the level / wells judged | 88 of 221 |
| Median | 150 mg/L |
| Years sampled | 1933–2022 |
| Wells | 221 |
| Test results | 454 |
| Wells left out | 40 |
| Sources | USGS (211), UTAHGS (6), UTAHDWQ_WQX (4) |