We read 28 results from City of Riverside’s 2025 water quality report. No results over a legal limit; 5 above a health goal or guideline.
Serves about 298,398 people · Water system ID CA3310031 · 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.
| Contaminant | Result | Health goal | Legal limit | What it means |
|---|---|---|---|---|
| Arsenicaverage · range ND to 4.6 · System · 2025 report, page 2 | 3.3 ppb | 0.004 ppb | 10 ppb | Above the health goal825x the health goal |
| Chromium-6average · range 2 to 2.2 · System · 2025 report, page 2 | 2.1 ppb | 0.02 ppb | 10 ppb | Above the health goal105x the health goal |
| Copper90th percentile of 51 homes tested, 0 over the action level · Customer taps (51 samples) · 2025 report, page 2 | 0.47 ppm | 0.3 ppm | 1.3 ppm (action level) | Above the health goal1.6x the health goal |
| Perchlorateaverage · range ND to 3.2 · System · 2025 report, page 2 | 2.3 ppb | 1 ppb | 6 ppb | Above the health goal2.3x the health goal |
| Uraniumaverage · range 7 to 14.8 · printed as 6.1 pCi/L pCi/L · System · 2025 report, page 2 | 9.09 ppb | 0.6 ppb | 30 ppb | Above the health goal15x the health goal |
| Aluminumaverage · range ND to 0.08 · printed as 22 ug/L ug/L · System · 2025 report, page 2 | 0.02 ppm | — | 0.2 ppm guideline | Within the guideline |
| Chlorideaverage · range 32 to 37 · System · 2025 report, page 2 | 34 ppm | — | 250 ppm guideline | Within the guideline |
| Chlorineaverage · range 0.25 to 0.85 · Distribution system · 2025 report, page 2 | 0.58 ppm | None set | 4 ppm | Below the legal limit |
| Disinfection byproducts (TTHM)highest running annual average · range 1 to 7.6 · Distribution system · 2025 report, page 2 | 6.1 ppb | None set | 80 ppb | Below the legal limit |
| Fluorideaverage · range 0.39 to 0.53 · System · 2025 report, page 2 | 0.45 ppm | 1 ppm | 2 ppm | Below the health goal |
| Gross alpha (radioactivity)average · range ND to 7 · System · 2025 report, page 2 | Not detected | 0 pCi/L | 15 pCi/L | Not detected |
| Lead90th percentile of 51 homes tested, 0 over the action level · Customer taps (51 samples) · 2025 report, page 2 | Not detected | 0.2 ppb | 15 ppb (action level) | Not detected |
| Nitrate (as N)average · range 4.7 to 6.5 · System · 2025 report, page 2 | 5.4 ppm | 10 ppm | 10 ppm | Below the health goal |
| pHaverage · range 7.4 to 8.1 · System · 2025 report, page 2 | 8 | — | — | Normal range |
| Radium (combined 226 + 228)average · range ND to 1.2 · System · 2025 report, page 2 | Not detected | 0 pCi/L | 5 pCi/L | Not detected |
| Sulfateaverage · range 58 to 78 · System · 2025 report, page 2 | 69 ppm | — | 250 ppm guideline | Within the guideline |
| Total dissolved solidsaverage · range 320 to 380 · System · 2025 report, page 2 | 357 ppm | — | 500 ppm guideline | Within the guideline |
| Turbidity (cloudiness)highest measured · John W. North Treatment Plant, highest of 2 sources · 2025 report, page 2 | 0.15 NTU | None set | 1 NTU | Below the legal limit |
| Alkalinityaverage · range 140 to 170 · System · 2025 report, page 2 | 157 ppm | None set | None | No health limit |
| Calciumaverage · range 60 to 68 · System · 2025 report, page 2 | 63 ppm | None set | None | No health limit |
| Hardnessaverage · range 10.5 to 12.3 · System · 2025 report, page 2 | 11.5 gpg (197 ppm) | — | — | Very hard |
| Lithiumaverage · range ND to 9.1 · sampled 2023 · System · 2025 report, page 2 | Not detected | None set | None | No health limit |
| Magnesiumaverage · range 8.1 to 9.6 · System · 2025 report, page 2 | 9 ppm | None set | None | No health limit |
| PFBA (a PFAS)average · range ND to 5.6 · sampled 2023 · System · 2025 report, page 2 | Not detected | None set | None | No health limit |
| PFHxA (a PFAS)average · range ND to 4.3 · sampled 2023 · System · 2025 report, page 2 | 3.6 ppt | None set | None | No health limit |
| PFPeA (a PFAS)average · range 5.6 to 8.7 · sampled 2023 · System · 2025 report, page 2 | 6.3 ppt | None set | None | No health limit |
| Potassiumaverage · range 3 to 3.5 · System · 2025 report, page 2 | 3 ppm | None set | None | No health limit |
| Sodiumaverage · range 38 to 47 · System · 2025 report, page 2 | 43 ppm | 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.
EPA testing for PFAS and lithium
EPA’s own nationwide testing (UCMR 5) found these in City of Riverside’s water between Feb 2023 and Nov 2023. These are EPA lab results, separate from the district’s report. Anything not listed was not detected.
- PFOS4 pptFound in 1 of 4 samples · highest resultBelow the federal limit that takes effect in 2029 (4 ppt)
- Lithium9.1 ppbFound in 2 of 4 samples · highest resultBelow EPA’s health reference level of 10 ppb
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.
Copper
Found: Copper
What removes it: Reverse osmosis.
Industrial chemicals and pesticides
Found: Perchlorate
What removes it: Carbon block or RO.
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