Kings County, CA
These figures come from wells tested in Kings County, CA, not from any one well.
- Iron is common in wells in Kings County, CA (8 of 39 tested wells were over that level), so it's worth testing for.
- Manganese is common in wells in Kings County, CA (14 of 38 tested wells were over that level), so it's worth testing for.
- Sulfate is common in wells in Kings County, CA (55 of 116 tested wells were over that level), so it's worth testing for.
- Wells in Kings County, CA are typically hard (112 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)
- manganese (common in wells here)
- sulfate (common in wells here)
- 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. California'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 | 21% |
| Wells over the level / wells judged | 8 of 39 |
| Median | 0.0494 mg/L |
| Years sampled | 1959–2024 |
| Wells | 40 |
| Test results | 93 |
| Wells left out | 93 |
| Sources | USGS (70) |
Manganese Recent
| Level it's compared with | 0.05 mg/L |
|---|---|
| Share of wells over the level | 37% |
| Wells over the level / wells judged | 14 of 38 |
| Median | 0.0349 mg/L |
| Years sampled | 1979–2024 |
| Wells | 41 |
| Test results | 83 |
| Wells left out | 86 |
| Sources | USGS (61) |
Hardness Recent
| Level it's compared with | none; hardness is shown in bands |
|---|---|
| Share of wells very hard | 38% |
| Median | 130 mg/L as CaCO₃ |
| Years sampled | 1946–2024 |
| Wells | 112 |
| Test results | 143 |
| Wells left out | 152 |
| Sources | USGS (112) |
Sulfate Recent
| Level it's compared with | 250 mg/L |
|---|---|
| Share of wells over the level | 47% |
| Wells over the level / wells judged | 55 of 116 |
| Median | 210 mg/L |
| Years sampled | 1946–2024 |
| Wells | 116 |
| Test results | 145 |
| Wells left out | 152 |
| Sources | USGS (116) |