Thurston County, WA
These figures come from wells tested in Thurston County, WA, not from any one well.
- Iron is common in wells in Thurston County, WA (13 of 78 tested wells were over that level), so it's worth testing for.
- Manganese and sulfate are not common in wells in Thurston County, WA (7 of 78 and 0 of 482 tested wells were over). Only a test tells you about your own well.
- Wells in Thurston County, WA are typically soft (450 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
- hardness
- sulfate
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. Washington'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 | 17% |
| Wells over the level / wells judged | 13 of 78 |
| Median | 0.1 mg/L |
| Years sampled | 1944–2017 |
| Wells | 78 |
| Test results | 960 |
| Wells left out | 30 |
| Sources | USGS (428), THURSTONCOUNTY (136) |
Manganese Recent
| Level it's compared with | 0.05 mg/L |
|---|---|
| Share of wells over the level | 9.0% |
| Wells over the level / wells judged | 7 of 78 |
| Median | 0.015 mg/L |
| Years sampled | 1962–2017 |
| Wells | 78 |
| Test results | 941 |
| Wells left out | 30 |
| Sources | USGS (407), THURSTONCOUNTY (137) |
Hardness Recent
| Level it's compared with | none; hardness is shown in bands |
|---|---|
| Share of wells very hard | 2.7% |
| Median | 52.7 mg/L as CaCO₃ |
| Years sampled | 1944–2016 |
| Wells | 450 |
| Test results | 575 |
| Wells left out | 0 |
| Sources | USGS (429), THURSTONCOUNTY (21) |
Sulfate Recent
| Level it's compared with | 250 mg/L |
|---|---|
| Share of wells over the level | 0.0% |
| Wells over the level / wells judged | 0 of 482 |
| Median | 4.2 mg/L |
| Years sampled | 1944–2017 |
| Wells | 482 |
| Test results | 617 |
| Wells left out | 30 |
| Sources | USGS (429), THURSTONCOUNTY (53) |