We read 35 results from Cws - Bakersfield’s 2025 water quality report. No results over a legal limit; 4 above a health goal or guideline.
Serves about 267,881 people · Water system ID CA1510003 · 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 |
|---|---|---|---|---|
| Arsenicaverage · range ND to 8.6 · Groundwater wells · 2025 report, page 13 | 2.1 ppb | 0.004 ppb | 10 ppb | Above the health goal525x the health goal |
| Chromium-6average · range ND to 3.4 · Groundwater wells · 2025 report, page 13 | 0.68 ppb | 0.02 ppb | 10 ppb | Above the health goal34x the health goal |
| Tetrachloroethylene (PCE)highest measured · range ND to 1.3 · Groundwater wells · 2025 report, page 14 | 1.3 ppb | 0.06 ppb | 5 ppb | Above the health goal22x the health goal |
| Uraniumaverage · range ND to 9.98 · printed as 1.4 pCi/L · Groundwater wells · 2025 report, page 13 | 2.09 ppb | 0.6 ppb | 30 ppb | Above the health goal3.5x the health goal |
| Aluminumaverage · range ND to 0.06 · Groundwater wells · 2025 report, page 13 | Not detected | — | 0.2 ppm guideline | Not detected |
| Bariumaverage · range ND to 0.18 · Groundwater wells · 2025 report, page 13 | Not detected | 2 ppm | 2 ppm | Not detected |
| Chlorideaverage · range 6.8 to 84 · Groundwater wells · 2025 report, page 15 | 19 ppm | — | 250 ppm guideline | Within the guideline |
| Chlorineaverage · range 0.27 to 2.2 · Distribution system · 2025 report, page 14 | 1.3 ppm | None set | 4 ppm | Below the legal limit |
| Copper90th percentile of 52 homes tested, 0 over the action level · sampled 2024 · Customer taps (52 sites) · 2025 report, page 13 | 0.11 ppm | 0.3 ppm | 1.3 ppm (action level) | Below the health goal |
| Disinfection byproducts (HAA5)highest running annual average · range ND to 58 · Distribution system · 2025 report, page 14 | 43 ppb | None set | 60 ppb | Below the legal limit |
| Disinfection byproducts (TTHM)highest running annual average · range ND to 120 · Distribution system · 2025 report, page 14 | 69 ppb | None set | 80 ppb | Below the legal limit |
| Fluorideaverage · range ND to 0.23 · Groundwater wells · 2025 report, page 13 | Not detected | 1 ppm | 2 ppm | Not detected |
| Gross alpha (radioactivity)average · range ND to 9 · Groundwater wells · 2025 report, page 13 | Not detected | 0 pCi/L | 15 pCi/L | Not detected |
| Ironaverage · range ND to 0.67 · printed as ND ppb · Groundwater wells · 2025 report, page 15 | Not detected | — | 0.3 ppm guideline | Not detected |
| Lead90th percentile of 52 homes tested, 0 over the action level · sampled 2024 · Customer taps (52 sites) · 2025 report, page 13 | Not detected | 0.2 ppb | 15 ppb (action level) | Not detected |
| Manganeseaverage · range ND to 0.05 · printed as ND ppb · Groundwater wells · 2025 report, page 15 | Not detected | — | 0.05 ppm guideline | Not detected |
| Nitrate (as N)average · range ND to 6.7 · Groundwater wells · 2025 report, page 13 | 1.4 ppm | 10 ppm | 10 ppm | Below the health goal |
| PFHxS (a PFAS)average · range ND to 12 · Groundwater wells · 2025 report, page 16 | Not detected | None set | 10 ppt from 2029 | Not detected |
| PFOA (a PFAS)average · range ND to 10 · Groundwater wells · 2025 report, page 16 | Not detected | 0.007 ppt | 4 ppt from 2029 | Not detected |
| PFOS (a PFAS)average · range ND to 14 · Groundwater wells · 2025 report, page 16 | Not detected | 1 ppt | 4 ppt from 2029 | Not detected |
| pHaverage · range 5.7 to 8.9 · Groundwater wells · 2025 report, page 16 | 7.7 | — | — | Normal range |
| Radium-228average · range ND to 1.7 · Groundwater wells · 2025 report, page 13 | Not detected | 0.02 pCi/L | 5 pCi/L | Not detected |
| Sulfateaverage · range 15 to 431 · Groundwater wells · 2025 report, page 15 | 34 ppm | — | 250 ppm guideline | Within the guideline |
| Total dissolved solidsaverage · range 150 to 880 · Groundwater wells · 2025 report, page 15 | 219 ppm | — | 500 ppm guideline | Within the guideline |
| Trichloroethylene (TCE)highest measured · range ND to 1.5 · Groundwater wells · 2025 report, page 14 | 1.5 ppb | 1.7 ppb | 5 ppb | Below the health goal |
| Turbidity (cloudiness)highest measured · Cal Water surface water plant · 2025 report, page 14 | 0.14 NTU | None set | 1 NTU | Below the legal limit |
| Alkalinityaverage · range 39 to 140 · Groundwater wells · 2025 report, page 16 | 91 ppm | None set | None | No health limit |
| Boronaverage · range 0.12 to 0.17 · Groundwater wells · 2025 report, page 16 | 0.15 ppm | None set | None | No health limit |
| Calciumaverage · range 11 to 140 · Groundwater wells · 2025 report, page 16 | 32 ppm | None set | None | No health limit |
| Hardnessaverage · range 3.04 to 22.2 · Groundwater wells · 2025 report, page 16 | 6.14 gpg (105 ppm) | — | — | Moderately hard |
| Magnesiumaverage · range 0.91 to 10 · Groundwater wells · 2025 report, page 16 | 4.4 ppm | None set | None | No health limit |
| PFBS (a PFAS)average · range ND to 5.9 · Groundwater wells · 2025 report, page 16 | 0.39 ppt | None set | None | No health limit |
| Potassiumaverage · range ND to 5.5 · Groundwater wells · 2025 report, page 16 | 1.6 ppm | None set | None | No health limit |
| Sodiumaverage · range 17 to 97 · Groundwater wells · 2025 report, page 16 | 25 ppm | None set | None | No health limit |
| Vanadiumaverage · range ND to 17 · Groundwater wells · 2025 report, page 16 | 7.5 ppb | 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. 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 Cws - Bakersfield’s water between Jul 2023 and Apr 2026. These are EPA lab results, separate from the district’s report. Anything not listed was not detected.
- PFOA9.1 pptFound in 3 of 98 samples · highest resultAbove the federal limit that takes effect in 2029 (4 ppt)
- PFOS14 pptFound in 19 of 98 samples · highest resultAbove the federal limit that takes effect in 2029 (4 ppt)
- PFHxS7.3 pptFound in 10 of 98 samples · highest resultNo federal limit in force for this one
- PFBS6.6 pptFound in 2 of 98 samples · highest resultNo federal limit in force for this one
- Lithium14.6 ppbFound in 22 of 98 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.
Industrial chemicals and pesticides
Found: Tetrachloroethylene (PCE)
What removes it: Carbon block or RO.
PFAS ("forever chemicals")
Found: PFOA (EPA testing), PFOS (EPA testing)
What removes it: Reverse osmosis.
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