Well Known

NJ

Bergen County, NJ

These figures come from wells tested in Bergen County, NJ, not from any one well.

What to test for

Start with the four this site covers:

Most well owners also test for these. We point to the source and don't interpret the results.

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 with0.3 mg/L
Share of wells over the level7.7%
Wells over the level / wells judged1 of 13
Median< DL mg/L
Years sampled1959–2025
Wells13
Test results190
Wells left out3
SourcesUSGS (130)

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 with0.05 mg/L
Share of wells over the level23%
Wells over the level / wells judged3 of 13
Median< 0.01 mg/L
Years sampled1959–2025
Wells13
Test results190
Wells left out3
SourcesUSGS (130)

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 withnone; hardness is shown in bands
Share of wells very hard42%
Median154 mg/L as CaCO₃
Years sampled1959–2025
Wells136
Test results205
Wells left out3
SourcesUSGS (136)

Sulfate Recent

Level it's compared with250 mg/L
Share of wells over the level4.2%
Wells over the level / wells judged6 of 142
Median25.75 mg/L
Years sampled1959–2025
Wells142
Test results231
Wells left out3
SourcesUSGS (142)