Ouray County, CO
These figures come from wells tested in Ouray County, CO, not from any one well.
- Sulfate is common in wells in Ouray County, CO (2 of 10 tested wells were over that level), so it's worth testing for.
- Wells in Ouray County, CO are typically very hard (10 wells tested).
- Too few wells have been tested in Ouray County, CO (9 each) to say how common iron or manganese is.
- Only a test of your own well tells you about your water.
What to test for
Start with the four this site covers:
- sulfate (common in wells here)
- iron
- 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. Colorado'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 Too few
| Level it's compared with | 0.3 mg/L |
|---|---|
| Share of wells over the level | 22% |
| Wells over the level / wells judged | 2 of 9 |
| Median | 0.0437 mg/L |
| Years sampled | 1974–2017 |
| Wells | 9 |
| Test results | 9 |
| Wells left out | 0 |
| Sources | USGS (9) |
Fewer than 10 wells behind this figure; treat it as a hint, not a prior.
Manganese Too few
| Level it's compared with | 0.05 mg/L |
|---|---|
| Share of wells over the level | 11% |
| Wells over the level / wells judged | 1 of 9 |
| Median | 0.005 mg/L |
| Years sampled | 1974–2017 |
| Wells | 9 |
| Test results | 9 |
| Wells left out | 0 |
| Sources | USGS (9) |
Fewer than 10 wells behind this figure; treat it as a hint, not a prior.
Hardness Older tests
| Level it's compared with | none; hardness is shown in bands |
|---|---|
| Share of wells very hard | 80% |
| Median | 230.5 mg/L as CaCO₃ |
| Years sampled | 1965–2017 |
| Wells | 10 |
| Test results | 10 |
| Wells left out | 0 |
| Sources | USGS (10) |
Sulfate Older tests
| Level it's compared with | 250 mg/L |
|---|---|
| Share of wells over the level | 20% |
| Wells over the level / wells judged | 2 of 10 |
| Median | 145 mg/L |
| Years sampled | 1965–2017 |
| Wells | 10 |
| Test results | 10 |
| Wells left out | 0 |
| Sources | USGS (10) |