We read 9 results from Coastside County Water District’s 2025 water quality report. No results over a legal limit; 1 above a health goal or guideline.
Serves about 18,940 people · Water system ID CA4110011 · Read the district’s 2025 report (opens in a new tab)
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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.
| Contaminant | Result | Health goal | Legal limit | What it means |
|---|---|---|---|---|
| Lead90th percentile of 42 homes tested, 0 over the action level · sampled 2024 · Customer taps · 2025 report, page 4 | 1.7 ppb | 0.2 ppb | 15 ppb (action level) | Above the health goal8.5x the health goal |
| Chlorideaverage · range 21 to 33 · Nunes WTP · 2025 report, page 4 | 26 ppm | — | 250 ppm guideline | Within the guideline |
| Chlorineaverage · range 0.2 to 1.46 · Distribution system · 2025 report, page 4 | 0.86 ppm | None set | 4 ppm | Below the legal limit |
| Copper90th percentile of 42 homes tested, 0 over the action level · sampled 2024 · Customer taps · 2025 report, page 4 | 0.08 ppm | 0.3 ppm | 1.3 ppm (action level) | Below the health goal |
| Disinfection byproducts (HAA5)highest running annual average · range 11 to 24 · Distribution system · 2025 report, page 4 | 24 ppb | None set | 60 ppb | Below the legal limit |
| Disinfection byproducts (TTHM)highest running annual average · range 32 to 66 · Distribution system · 2025 report, page 4 | 53 ppb | None set | 80 ppb | Below the legal limit |
| Sulfateaverage · range 18 to 28 · Nunes WTP · 2025 report, page 4 | 22 ppm | — | 250 ppm guideline | Within the guideline |
| Total dissolved solidsaverage · range 124 to 234 · Nunes WTP · 2025 report, page 4 | 178 ppm | — | 500 ppm guideline | Within the guideline |
| Conductivityaverage · range 228 to 359 · Nunes WTP · 2025 report, page 4 | 303 µS/cm | None set | None | No 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.
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.
Lead
Found: Lead
What removes it: Certified carbon block or RO.
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