Total Trihalomethanes
Approaching LimitDetected level
53.975 ug/L
68% of EPA limit
Health effects: Disinfection byproducts linked to increased risk of bladder cancer and reproductive issues with long-term exposure.
Tap Water Safety Report for Garden Grove, California
Garden Grove, California tap water scored 54/100 (D) based on EPA data. Multiple contaminants are at concerning levels. A water filter is recommended, especially for children and pregnant women.
Overall Score
54/100
Grade: D
Contaminants Tested
8
All within limits
EPA Violations
8
All resolved
Water Source
mixed
Mixed sources
Population Served
176,920
residents
Water Systems
1
serving this area
2 contaminant(s) are approaching EPA limits and should be monitored.
Detected level
53.975 ug/L
68% of EPA limit
Health effects: Disinfection byproducts linked to increased risk of bladder cancer and reproductive issues with long-term exposure.
Detected level
0.6782 mg/L
52% of EPA limit
Health effects: Can cause gastrointestinal distress at high levels. Long-term exposure may damage the liver and kidneys.
Based on Garden Grove's water quality data, here are our specific recommendations:
Garden Grove's water has multiple contaminants at concerning levels. An under-sink reverse osmosis system or a certified multi-stage filter is strongly recommended for drinking and cooking water.
Babies and young children are especially vulnerable to water contaminants. Use filtered or bottled water for mixing formula and for drinking water until filtration is installed.
How contaminant levels compare to EPA limits (50% of overall score)
EPA violation history and enforcement actions (30% of overall score)
Water system infrastructure and source quality (20% of overall score)
With a score of 54/100, Garden Grove's tap water has significant quality concerns. We strongly recommend against using unfiltered tap water for babies or young children. Use bottled water or invest in a reverse osmosis filter for any water consumed by children. Infants are especially vulnerable to contaminants like lead and nitrates, which can cause serious developmental and health issues.
Garden Grove's water has been tested for 8 contaminants. None currently exceed EPA maximum contaminant levels. The most notable detections include: Total Trihalomethanes (53.975 ug/L, EPA limit: 80 ug/L — 68% of limit); Copper (0.6782 mg/L, EPA limit: 1.3 mg/L — 52% of limit); Mercury (0.0009 mg/L, EPA limit: 0.002 mg/L — 46% of limit); Lead (0.0055 mg/L, EPA limit: 0.015 mg/L — 37% of limit); Fluoride (1.4244 mg/L, EPA limit: 4 mg/L — 36% of limit). The water system has no active EPA violations. Water quality can vary seasonally and by neighborhood, so home testing provides the most accurate picture for your specific tap.
Absolutely. With a water quality score of 54/100, filtering is strongly recommended in Garden Grove. A reverse osmosis (RO) system is the most effective option, removing up to 99% of contaminants. At minimum, use a certified pitcher filter rated for the specific contaminants found in your water. Multiple contaminants at concerning levels make filtration an important health measure.
Garden Grove's water quality score of 54/100 (D) is 18 points below the national average of 72. The city's water comes from a mix of groundwater and surface water sources. This indicates significant water quality challenges that the city should work to address. You can see how Garden Grove compares to nearby cities in our state rankings.
Detailed contaminant data, violation history, and water system information for Garden Grove.
Find the best water filter for Garden Grove based on detected contaminants and your budget.
See how Garden Grove compares to other cities across California.
See how Garden Grove ranks among all cities in the US for water quality.
Data Disclaimer
This report is based on publicly available EPA data and water quality test results. Water quality can vary by neighborhood, building age, and season. This information is for educational purposes and should not replace professional water testing. If you have specific health concerns about your water, contact your local water utility or a certified water testing laboratory. Last data update: February 2, 2026.