Shoal & Stem

Middletown, CA tap water

About 49% of Middletown is inside a utility's service area. Homes outside it likely use private wells, which no utility tests.

Disinfectant

Chlorine

Utility water here is treated with chlorine. It slowly gases off from standing water, and any water conditioner removes it. Private wells aren't treated by a utility, so there's no chlorine or chloramine unless a treatment system adds it.

Safety for fish and shrimp

Nitrate (NO₃)

Not detected (Low)

Not detected in testing, so water changes lower your tank's nitrate well.

From California Water Board lab results, measured before treatment (2023–2026).

Copper at home taps

Not detected (Low)

Not detected in testing. Water that sits in household pipes overnight can still pick some up.

From California Water Board lab results (2025).

Water chemistry

General hardness

160–170 ppm

Typical 165 ppm

Moderately hard. Great for livebearers, and most community fish adapt.

From California Water Board lab results, measured before treatment (2024–2025).

Carbonate hardness (alkalinity)

170–240 ppm

Typical 205 ppm

Strong buffering. pH stays steady and hard to lower without RO water.

From California Water Board lab results, measured before treatment (2024–2025).

pH

7.5–7.6

Typical 7.5

Most community fish do well here. Stable water matters more than the exact number.

From California Water Board lab results, measured before treatment (2024–2025).

Total dissolved solids

190–330 ppm

Typical 260 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 California Water Board lab results, measured before treatment (2024–2025).

Who supplies Middletown, CA

  • Callayomi County Water District

    Serves 49% 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.

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