Malheur County, OR
These figures come from wells tested in Malheur County, OR, not from any one well.
- Manganese is common in wells in Malheur County, OR (8 of 39 tested wells were over that level), so it's worth testing for.
- Sulfate is common in wells in Malheur County, OR (28 of 144 tested wells were over that level), so it's worth testing for.
- Iron is not common in wells in Malheur County, OR (1 of 38 tested wells were over). Only a test tells you about your own well.
- Wells in Malheur County, OR are typically very hard (144 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:
- manganese (common in wells here)
- sulfate (common in wells here)
- iron
- 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. Oregon'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 | 2.6% |
| Wells over the level / wells judged | 1 of 38 |
| Median | < 0.25 mg/L |
| Years sampled | 1954–2015 |
| Wells | 38 |
| Test results | 1,256 |
| Wells left out | 8 |
| Sources | OREGONDEQ (131), USGS (7) |
More than half the wells had results below the lab's detection limit, so the median is reported as below that limit.
Manganese Recent
| Level it's compared with | 0.05 mg/L |
|---|---|
| Share of wells over the level | 21% |
| Wells over the level / wells judged | 8 of 39 |
| Median | < 0.05 mg/L |
| Years sampled | 1977–2015 |
| Wells | 39 |
| Test results | 1,239 |
| Wells left out | 8 |
| Sources | OREGONDEQ (132), USGS (5) |
More than half the wells had results below the lab's detection limit, so the median is reported as below that limit.
Hardness Recent
| Level it's compared with | none; hardness is shown in bands |
|---|---|
| Share of wells very hard | 83% |
| Median | 301.5 mg/L as CaCO₃ |
| Years sampled | 1954–2015 |
| Wells | 144 |
| Test results | 1,900 |
| Wells left out | 8 |
| Sources | OREGONDEQ (131), USGS (13) |
Sulfate Recent
| Level it's compared with | 250 mg/L |
|---|---|
| Share of wells over the level | 19% |
| Wells over the level / wells judged | 28 of 144 |
| Median | 155 mg/L |
| Years sampled | 1954–2015 |
| Wells | 144 |
| Test results | 1,247 |
| Wells left out | 6 |
| Sources | OREGONDEQ (131), USGS (13) |