Shoreline, WA tap water
Supplied mostly by Seattle Public Utilities, 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
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)
Up to 0.4 ppm (Low)
Typical 0.2 ppm
Low, so water changes lower your tank's nitrate well.
From EPA monitoring data; Seattle Public Utilities, which supplies North City Water District (2012–2019).
Chlorine or chloramine at the tap
0–1.8 ppm
Typical 1 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: Seattle Public Utilities' 2025 water quality report.
Water chemistry
General hardness
25 ppm
Soft. Good for tetras, rasboras and most shrimp. Livebearers, snails and African cichlids prefer harder water.
From Seattle Public Utilities' website; Seattle Public Utilities, which supplies North City Water District.
Carbonate hardness (alkalinity)
23 ppm
Little buffering. pH can drop quickly between water changes, especially with CO₂ or an older tank.
From Seattle Public Utilities' website; Seattle Public Utilities, which supplies North City Water District.
pH
7.5–8.5
Typical 8.3
Alkaline. Many utilities raise pH to protect pipes. Stability matters more than the exact number.
From Seattle Public Utilities' website; Seattle Public Utilities, which supplies North City Water District.
Total dissolved solids
36 ppm
A rough measure of everything dissolved in the water. RO water reads near 0, so TDS is a quick way to compare waters.
From Seattle Public Utilities' website; Seattle Public Utilities, which supplies North City Water District.
Who supplies Shoreline, WA
- 2025 water quality report
Seattle Public Utilities
Serves 62% of residents · Lake or river water · Chlorine
North City Water District
Serves 33% of residents · Buys water from Seattle Public Utilities · 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.