Well Water Nerd

Copper in Idaho well water

In Idaho, 0% of 4,969 tested private well samples exceeded the EPA limit for copper (1.3 mg/L).

Copper leaches from pipes when water is acidic. Above 1.3 mg/L it causes stomach upset, and long-term exposure can harm the liver and kidneys. Blue-green stains on fixtures are the giveaway.

Check your copper number

Type the value from your lab report. It is compared to the EPA limit, the same way the full interpretation does it.

Getting it fixed

Book a free in-home water test with a licensed local company, or see the treatment guide for what removes copper.

By county, from individual samples

Public monitoring samples against the EPA limit (1.3 mg/L); counties with at least 30 samples.

CountySamplesDetectedAbove EPA limitMedianHighest
Twin Falls32083%0%0.0020.25 mg/L
Gooding7683%0%0.0020.026 mg/L
Lemhi8080%0%0.0030.12 mg/L
Lewis6379%0%0.0020.059 mg/L
Caribou10278%0%0.0020.055 mg/L
Cassia11777%0%0.0020.026 mg/L
Bingham13775%0%0.0010.016 mg/L
Blaine8870%0%0.0020.035 mg/L
Oneida3370%0%0.0020.025 mg/L
Teton4670%0%0.0010.1 mg/L
Clearwater4468%0%0.0010.007 mg/L
Fremont11766%0%0.0020.15 mg/L
Custer6464%0%0.0010.04 mg/L
Franklin3563%0%0.0020.094 mg/L
Lincoln7362%0%0.0010.026 mg/L

Sources

  • Individual samples from the USGS Water Quality Portal and state monitoring, summarized per geography. copper counts and shares are listed on each county and town page with their sources.