Columbia, MD tap water
Supplied by Howard County Department of Public Works, Bureau of Utilities. Here's what its 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)
6.2–7.5 ppm (Low)
Typical 7 ppm
Water changes can't take your tank's nitrate below this level.
Published by your utility: Howard County Department of Public Works, Bureau of Utilities' 2024 water quality report.
Copper at home taps (first draw)
Up to 0.2 ppm (Worth knowing)
The 90th percentile of first-draw samples from homes: water that sat in household pipes for at least six hours.
Shrimp and snails are sensitive to copper. Water that sits in household pipes picks up the most; it drops once the tap has run for a minute.
Published by your utility: Howard County Department of Public Works, Bureau of Utilities' 2024 water quality report.
Chlorine or chloramine at the tap
0.1–1.4 ppm
Typical 0.4 ppm
At tap levels, chlorine and chloramine are toxic to fish, shrimp and the bacteria in a filter. Water conditioners are made for this range.
Published by your utility: Howard County Department of Public Works, Bureau of Utilities' 2024 water quality report.
Water chemistry
General hardness
Not published yet
We haven't found this number yet. A drop test kit gives you your exact reading.
Carbonate hardness (alkalinity)
Not published yet
We haven't found this number yet. A drop test kit gives you your exact reading.
pH
Not published yet
We haven't found this number yet. A drop test kit gives you your exact reading.
- Howard County Department of Public Works, Bureau of Utilities adds phosphate to protect pipes. It can feed algae in tanks without much plant growth.
- Howard County Department of Public Works, Bureau of Utilities softens its water at the plant, so it may be softer than the local groundwater.
Who supplies Columbia, MD
- 2024 water quality report
Howard County Department of Public Works, Bureau of Utilities
Serves 96% of residents · Buys water from City of Baltimore · 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.