Whatcom County, WA
These figures come from wells tested in Whatcom County, WA, not from any one well.
- Iron is common in wells in Whatcom County, WA (6 of 35 tested wells were over that level), so it's worth testing for.
- Manganese is common in wells in Whatcom County, WA (13 of 33 tested wells were over that level), so it's worth testing for.
- Sulfate is not common in wells in Whatcom County, WA (1 of 221 tested wells were over). Only a test tells you about your own well.
- Wells in Whatcom County, WA are typically moderately hard (297 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)
- 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 | 6 of 35 |
| Median | 0.0228 mg/L |
| Years sampled | 1949–2018 |
| Wells | 35 |
| Test results | 448 |
| Wells left out | 39 |
| Sources | USGS (289), LUMMINSN_WQX (53) |
Manganese Recent
| Level it's compared with | 0.05 mg/L |
|---|---|
| Share of wells over the level | 39% |
| Wells over the level / wells judged | 13 of 33 |
| Median | 0.0226 mg/L |
| Years sampled | 1962–2018 |
| Wells | 33 |
| Test results | 243 |
| Wells left out | 39 |
| Sources | USGS (197) |
Hardness Recent
| Level it's compared with | none; hardness is shown in bands |
|---|---|
| Share of wells very hard | 14% |
| Median | 113.8 mg/L as CaCO₃ |
| Years sampled | 1948–2024 |
| Wells | 297 |
| Test results | 406 |
| Wells left out | 39 |
| Sources | USGS (238), LUMMINSN_WQX (59) |
Sulfate Recent
| Level it's compared with | 250 mg/L |
|---|---|
| Share of wells over the level | 0.5% |
| Wells over the level / wells judged | 1 of 221 |
| Median | 16 mg/L |
| Years sampled | 1949–2018 |
| Wells | 221 |
| Test results | 285 |
| Wells left out | 37 |
| Sources | USGS (206), LUMMINSN_WQX (15) |