Barnstable Town, MA tap water
Supplied mostly by Centerville Osterville Marstons Mills WD, plus 3 other utilities. 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
Nitrite (NO₂)
Not detected (Low)
Not detected in testing, so any nitrite in your tank comes from the tank itself.
From EPA monitoring data (2012–2019).
Nitrate (NO₃)
0.5–20 ppm (Low)
Typical 8.5 ppm
Water changes can't take your tank's nitrate below this level.
From EPA monitoring data (2012–2019).
Water chemistry
General hardness
Area estimate14–93 ppm
Typical 24 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 county (2000–2023).
Carbonate hardness (alkalinity)
Area estimate0–14 ppm
Typical 9 ppm
Little buffering. pH can drop quickly between water changes, especially with CO₂ or an older tank.
Area estimate from nearby wells: USGS well samples in your county (2000–2016).
pH
5.4–7.8
Typical 7.2
Most community fish do well here. Stable water matters more than the exact number.
From EPA monitoring data (2013–2019).
Total dissolved solids
Area estimate60–315 ppm
Typical 134 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 (2000–2019).
- Centerville Osterville Marstons Mills WD and Hyannis Water System, Town of Barnstable add phosphate to protect pipes. It can feed algae in tanks without much plant growth.
Who supplies Barnstable Town, MA
Centerville Osterville Marstons Mills WD
Serves 46% of residents · Groundwater (wells) · Chlorine
Hyannis Water System, Town of Barnstable
Serves 34% of residents · Groundwater (wells) · Chlorine
Cotuit Fire District Water Department
Serves 7% of residents · Groundwater (wells) · Chlorine
Barnstable Fire District
Serves 7% of residents · Groundwater (wells) · 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.