A92/100
Downey Tap Water Quality: Is It Safe to Drink? (2026 Report)
Serving 310,037 residents · California
What's In Downey's Tap Water?
70
Contaminants Tested
2
Exceed EPA Limits
1
Above EPA Goals
3 contaminants above EPA health goals
| Contaminant | Detected | Limit (MCL) | Status |
|---|---|---|---|
PFOS | 0.044 µg/L | 0.004 µg/L | Over Limit |
PFOA | 0.015 µg/L | 0.004 µg/L | Over Limit |
1,4-dioxane | 2.20 µg/L | — | Above Goal |
EPA Violation History
No violations in the past 5 years
Full EPA compliance since 2018.
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
LIBERTY UTILITIES - COMPTON
Population Served
26,371
Water Source
Purchased Surface Water
System ID
CA1910021
LIBERTY UTILITIES - LYNWOOD
Population Served
24,701
Water Source
Purchased Surface Water
System ID
CA1910161
LIBERTY UTILITIES - BELLFLOWER-NORWALK
Population Served
72,624
Water Source
Purchased Surface Water
System ID
CA1910211
LIBERTY UTILITIES - MESA CREST
Population Served
1,619
Water Source
Purchased Surface Water
System ID
CA1910241
DOWNEY - CITY, WATER DEPT.
Population Served
108,816
Water Source
Groundwater
System ID
CA1910034
CITY OF BELL GARDENS
Population Served
11,437
Water Source
Purchased Surface Water
System ID
CA1910108
LIBERTY UTILITIES (AV RANCHOS) CORP.
Population Served
64,469
Water Source
Groundwater
System ID
CA3610003
Frequently Asked Questions About Downey Water
Is Downey tap water safe to drink?
Downey, California tap water receives a grade of A (92/100), which is considered excellent. Out of 79 contaminants tested, 2 exceed EPA maximum contaminant levels (MCLs) and 5 exceed health guidelines (MCLGs). While the water meets federal standards, some residents may still choose to use a filter for additional peace of mind.
What contaminants are in Downey's water?
Of the 79 contaminants tested in Downey's water supply, the most notable include PFOS, PFOA, Lead (90th percentile), vanadium, 1,4-dioxane. 2 contaminant(s) exceed EPA legal limits (MCLs). 5 contaminant(s) exceed EPA health goals (MCLGs), which are non-enforceable targets set at levels with no known health risk.
Does Downey have any water quality violations?
Yes, Downey has 11 EPA violation(s) on record, with the most recent in 2021. Violation types include MR, TT, MCL. 4 of these are health-based violations, which are the most serious category.
Do I need a water filter in Downey?
Based on EPA data, using a water filter in Downey is recommended. 2 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 Downey's tap water come from?
Downey's drinking water is sourced from purchased surface water and supplied by LIBERTY UTILITIES - COMPTON and 6 other water system(s). The system serves approximately 310,037 people. Surface water sources include rivers, lakes, and reservoirs.
How often is Downey'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. Downey'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 Downey's water compare to other cities in California?
Downey's water quality score of 92/100 earns a grade of A, which is considered excellent. This places Downey among the better-performing water systems in California. Visit our California state page to see how all cities in the state compare.
What should I do if I'm concerned about Downey's water quality?
If you have concerns about Downey'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 (LIBERTY UTILITIES - COMPTON) 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.