Erwin, TN tap water
Supplied mostly by Erwin Utilities Authority, plus 1 other utility. Here's what the water means for your fish.
Disinfectant
Chlorine
Your water is treated with chlorine. It slowly gases off from standing water, and any water conditioner removes it.
Safety for fish and shrimp
Nitrate (NO₃)
3.3–15 ppm (Low)
Typical 4.3 ppm
Low, so water changes lower your tank's nitrate well.
From EPA monitoring data; Erwin Utilities Authority, which supplies Unicoi Utility District (2014–2019).
Water chemistry
General hardness
Area estimate11–296 ppm
Typical 54 ppm
Soft. Good for tetras, rasboras and most shrimp. Livebearers, snails and African cichlids prefer harder water.
Area estimate from nearby wells: USGS well samples in your state (2000–2023).
Carbonate hardness (alkalinity)
Area estimate10–270 ppm
Typical 65 ppm
Moderate buffering. pH should stay fairly steady.
Area estimate from nearby wells: USGS well samples in your state (2000–2024).
pH
7.5–7.8
Typical 7.7
Most community fish do well here. Stable water matters more than the exact number.
From EPA monitoring data; Erwin Utilities Authority, which supplies Unicoi Utility District (2015–2018).
Total dissolved solids
Area estimate34–347 ppm
Typical 92 ppm
A rough measure of everything dissolved in the water. RO water reads near 0, so TDS is a quick way to compare waters.
Area estimate from nearby wells: USGS well samples in your state (2000–2023).
- Erwin Utilities Authority and Unicoi Utility District add phosphate to protect pipes. It can feed algae in tanks without much plant growth.
Who supplies Erwin, TN
Erwin Utilities Authority
Serves 96% of residents · Groundwater fed by surface water · Chlorine
Unicoi Utility District
Serves 5% of residents · Buys water from Erwin Utilities Authority · Chlorine
Our data comes from public records and is still incomplete. Many utilities don't publish every number, so we're adding more all the time. Your city's range is a starting point: testing your own tap is the only way to know exactly what's in it.
Tap water lookup covers US cities only for now. Want to know why it matters? Read our story on tap water.
Compiled by Shoal & Stem from public records. Free to cite with a link.