C54/100
Atwater Tap Water Quality: Is It Safe to Drink? (2026 Report)
Serving 29,479 residents · California
What's In Atwater's Tap Water?
66
Contaminants Tested
3
Exceed EPA Limits
1
Above EPA Goals
4 contaminants above EPA health goals
| Contaminant | Detected | Limit (MCL) | Status |
|---|---|---|---|
PFHxS | 0.059 µg/L | 0.010 µg/L | Over Limit |
PFOS | 0.045 µg/L | 0.004 µg/L | Over Limit |
PFOA | 0.033 µg/L | 0.004 µg/L | Over Limit |
vanadium | 36.00 µg/L | — | Above Goal |
EPA Violation History
No violations in the past 5 years
Full EPA compliance since 2014.
Understanding violation severity
Tier 1Urgent health risk. Utility must notify all customers within 24 hours.Tier 2Important health or treatment issue. Customers notified within 30 days.Tier 3Administrative or monitoring issue. Reported in the annual water quality report.
Source: EPA Safe Drinking Water Information System (SDWIS) · Updated quarterly
Water Utility Details
CITY OF ATWATER
Population Served
29,479
Water Source
Groundwater
System ID
CA2410001
Frequently Asked Questions About Atwater Water
Is Atwater tap water safe to drink?
Atwater, California tap water receives a grade of C (54/100), which is considered fair. 3 contaminant(s) exceed EPA maximum contaminant levels and 7 violation(s) are on record. Residents should consider using an NSF-certified water filter to reduce contaminant exposure.
What contaminants are in Atwater's water?
Of the 66 contaminants tested in Atwater's water supply, the most notable include PFOS, PFOA, PFHxS, vanadium. 3 contaminant(s) exceed EPA legal limits (MCLs). 4 contaminant(s) exceed EPA health goals (MCLGs), which are non-enforceable targets set at levels with no known health risk.
Does Atwater have any water quality violations?
Yes, Atwater has 7 EPA violation(s) on record, with the most recent in 2014. Violation types include MR, MCL. 3 of these are health-based violations, which are the most serious category.
Do I need a water filter in Atwater?
Based on EPA data, using a water filter in Atwater is recommended. 3 contaminant(s) exceed legal limits. An NSF-certified filter — such as a reverse osmosis or activated carbon system — can effectively reduce many common contaminants. Choose a filter certified to remove the specific contaminants found in your area.
Where does Atwater's tap water come from?
Atwater's drinking water is sourced from groundwater and supplied by CITY OF ATWATER. The system serves approximately 29,479 people. Groundwater is pumped from underground aquifers, which often provides natural filtration.
How often is Atwater's water tested?
Under the Safe Drinking Water Act (SDWA), water utilities are required to regularly test for over 90 contaminants. Testing frequency varies by contaminant — some are tested monthly, others quarterly or annually. Atwater's water systems must report results to the EPA and publish an annual Consumer Confidence Report (CCR). The data on this page reflects the latest available EPA testing data.
How does Atwater's water compare to other cities in California?
Atwater's water quality score of 54/100 earns a grade of C, which is considered fair. This is a below-average score that indicates room for improvement. Visit our California state page to see how all cities in the state compare.
What should I do if I'm concerned about Atwater's water quality?
If you have concerns about Atwater's tap water, consider these steps: (1) Request your utility's annual Consumer Confidence Report for detailed local data. (2) Get your water independently tested through a state-certified laboratory. (3) Consider an NSF-certified water filter rated for the contaminants found in your area. (4) Contact your water utility (CITY OF ATWATER) with specific questions. (5) Report water quality issues to your state drinking water program or the EPA Safe Drinking Water Hotline at 800-426-4791.