We read 10 results from Johnstown Town of’s 2025 water quality report. No results over a legal limit; 3 above a health goal or guideline.
Serves about 24,725 people · Water system ID CO0162418 · Read the district’s 2025 report (opens in a new tab)
Open this district in the water lookupCompare with your own test results, see the district map and get matched filters.
Results from the 2025 report
Each number is copied from the district’s report and links to the page it’s printed on. Where the report lists several plants, wells or purchased water, the highest is shown.
| Contaminant | Result | Health goal | Legal limit | What it means |
|---|---|---|---|---|
| Gross alpha (radioactivity)average · range 0.3 to 0.3 · sampled 2022 · Entry point · 2025 report, page 9 | 0.3 pCi/L | 0 pCi/L | 15 pCi/L | Above the health goalThe health goal is zero |
| Lead90th percentile of 31 homes tested, 0 over the action level · Customer taps · 2025 report, page 7 | 1 ppb | 0.2 ppb | 15 ppb (action level) | Above the health goal5x the health goal |
| Radium (combined 226 + 228)average · range 0.5 to 0.5 · sampled 2023 · Entry point · 2025 report, page 9 | 0.5 pCi/L | 0 pCi/L | 5 pCi/L | Above the health goalThe health goal is zero |
| Bariumaverage · range 0.03 to 0.03 · sampled 2023 · Entry point · 2025 report, page 9 | 0.03 ppm | 2 ppm | 2 ppm | Below the health goal |
| Copper90th percentile of 31 homes tested, 0 over the action level · Customer taps · 2025 report, page 7 | 0.06 ppm | 0.3 ppm | 1.3 ppm (action level) | Below the health goal |
| Disinfection byproducts (HAA5)average · range 10.6 to 36.7 · Distribution system · 2025 report, page 8 | 23.2 ppb | None set | 60 ppb | Below the legal limit |
| Disinfection byproducts (TTHM)average · range 15.3 to 46.7 · Distribution system · 2025 report, page 8 | 31.1 ppb | None set | 80 ppb | Below the legal limit |
| Nitrate (as N)average · range 0.1 to 0.1 · Entry point · 2025 report, page 9 | 0.1 ppm | 10 ppm | 10 ppm | Below the health goal |
| Turbidity (cloudiness)highest measured · Entry point · 2025 report, page 8 | 0.42 NTU | None set | 1 NTU | Below the legal limit |
| Sodiumaverage · range 17 to 17 · sampled 2023 · Entry point · 2025 report, page 10 | 17 ppm | None set | None | No health limit |
Utility results describe the whole system, measured where water enters the pipes, not your tap. Your home’s plumbing can add lead or copper.
What you can do
Nothing here is an emergency notice: if the district has a violation, it must tell customers directly. If you’d like to lower these at your tap, these are the treatments that remove them, and the catalog shows the models certified for each. Ranking is by certified removal; commissions never change the order.
Radium and uranium
Found: Gross alpha (radioactivity), Radium (combined 226 + 228)
What removes it: Reverse osmosis.
Lead
Found: Lead
What removes it: Certified carbon block or RO.
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