City of Delano water quality

Updated 2026-10-22 · California · Affiliate disclosure

We read 17 results from City of Delano’s 2025 water quality report. No results over a legal limit; 2 above a health goal or guideline.

Serves about 51,428 people · Water system ID CA1510005 · Read the district’s 2025 report (opens in a new tab)

Open this district in the water lookupCompare with your own test results, see the district map and get matched filters.

Results from the 2025 report

Each number is copied from the district’s report and links to the page it’s printed on. Where the report lists several plants, wells or purchased water, the highest is shown.

ContaminantResultHealth goalLegal limitWhat it means
Arsenicaverage · range ND to 11 · Wells · 2025 report, page 34.46 ppb0.004 ppb10 ppbAbove the health goal1,115x the health goal
Chromium-6average · range 0.2 to 9.1 · Wells · 2025 report, page 44.14 ppb0.02 ppb10 ppbAbove the health goal207x the health goal
Bariumaverage · range ND to 0.15 · sampled 2023 · Wells · 2025 report, page 40.03 ppm2 ppm2 ppmBelow the health goal
Chlorideaverage · range 18 to 120 · sampled 2023 · Wells · 2025 report, page 857 ppm—250 ppm guidelineWithin the guideline
Chlorineaverage · range 1.2 to 2.98 · Distribution system · 2025 report, page 52.2 ppmNone set4 ppmBelow the legal limit
Copper90th percentile of 48 homes tested, 0 over the action level · sampled 2023 · Customer taps · 2025 report, page 30.01 ppm0.3 ppm1.3 ppm (action level)Below the health goal
Disinfection byproducts (HAA5)average · range ND to 12 · Distribution system · 2025 report, page 45.4 ppbNone set60 ppbBelow the legal limit
Disinfection byproducts (TTHM)average · range ND to 70 · Distribution system · 2025 report, page 418.4 ppbNone set80 ppbBelow the legal limit
Fluorideaverage · range 0.12 to 0.53 · sampled 2023 · Wells · 2025 report, page 40.29 ppm1 ppm2 ppmBelow the health goal
Lead90th percentile of 48 homes tested, 0 over the action level · sampled 2023 · Customer taps · 2025 report, page 3Not detected0.2 ppb15 ppb (action level)Not detected
Nitrate (as N)average · range ND to 1.92 · Wells · 2025 report, page 40.94 ppm10 ppm10 ppmBelow the health goal
Nitrite (as N)average · range ND to 0.09 · Wells · 2025 report, page 40.0026 ppm1 ppm1 ppmBelow the health goal
Seleniumaverage · range ND to 2.8 · sampled 2023 · Wells · 2025 report, page 40.92 ppb30 ppb50 ppbBelow the health goal
Sulfateaverage · range 27 to 120 · sampled 2023 · Wells · 2025 report, page 868 ppm—250 ppm guidelineWithin the guideline
Total dissolved solidsaverage · range 220 to 500 · sampled 2023 · Wells · 2025 report, page 8348 ppm—500 ppm guidelineWithin the guideline
Hardnessaverage · range 0.64 to 8.19 · sampled 2023 · Wells · 2025 report, page 32.75 gpg (47.1 ppm)——Soft
Sodiumaverage · range 45 to 120 · sampled 2023 · Wells · 2025 report, page 385.7 ppmNone setNoneNo health limit

Utility results describe the whole system, measured where water enters the pipes, not your tap. Your home’s plumbing can add lead or copper. 1 number we weren’t sure about is held back until a person checks.

EPA testing for PFAS and lithium

EPA’s own nationwide testing (UCMR 5) found these in City of Delano’s water between Mar 2024 and Sep 2024. These are EPA lab results, separate from the district’s report. Anything not listed was not detected.

  • Lithium21.1 ppbFound in 5 of 24 samples · highest resultAbove EPA’s health reference level of 10 ppb (a guide, not a legal limit)

Source: EPA UCMR 5 occurrence data. The highest single result is shown; one high sample doesn’t mean every glass is that high.

What you can do

Nothing here is an emergency notice: if the district has a violation, it must tell customers directly. If you’d like to lower these at your tap, these are the treatments that remove them, and the catalog shows the models certified for each. Ranking is by certified removal; commissions never change the order.

Arsenic

Found: Arsenic

What removes it: Reverse osmosis.

See filters that remove it

Chromium-6

Found: Chromium-6

What removes it: Reverse osmosis.

See filters that remove it

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