Graham County, AZ
These figures come from wells tested in Graham County, AZ, not from any one well.
- Sulfate is common in wells in Graham County, AZ (115 of 302 tested wells were over that level), so it's worth testing for.
- Iron and manganese are not common in wells in Graham County, AZ (4 of 134 and 7 of 134 tested wells were over). Only a test tells you about your own well.
- Wells in Graham County, AZ are typically hard (400 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:
- 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. Arizona'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 | 3.0% |
| Wells over the level / wells judged | 4 of 134 |
| Median | < 0.2 mg/L |
| Years sampled | 1952–2014 |
| Wells | 134 |
| Test results | 532 |
| Wells left out | 0 |
| Sources | USGS (125), 21ARIZGW (107), AZDEQ_GW (103) |
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 | 5.2% |
| Wells over the level / wells judged | 7 of 134 |
| Median | < 0.05 mg/L |
| Years sampled | 1956–2014 |
| Wells | 134 |
| Test results | 525 |
| Wells left out | 0 |
| Sources | USGS (121), 21ARIZGW (106), AZDEQ_GW (103) |
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 | 49% |
| Median | 170 mg/L as CaCO₃ |
| Years sampled | 1933–2014 |
| Wells | 400 |
| Test results | 824 |
| Wells left out | 0 |
| Sources | USGS (196), AZDEQ_GW (103), 21ARIZGW (101) |
Sulfate Recent
| Level it's compared with | 250 mg/L |
|---|---|
| Share of wells over the level | 38% |
| Wells over the level / wells judged | 115 of 302 |
| Median | 147.5 mg/L |
| Years sampled | 1933–2021 |
| Wells | 302 |
| Test results | 534 |
| Wells left out | 0 |
| Sources | USGS (195), AZDEQ_GW (107) |