A97/100
Arnold Tap Water Quality: Is It Safe to Drink? (2026 Report)
Serving 38,113 residents · Missouri
What's In Arnold's Tap Water?
69
Contaminants Tested
0
Exceed EPA Limits
2
Above EPA Goals
2 contaminants above EPA health goals
| Contaminant | Detected | Limit (MCL) | Status |
|---|---|---|---|
chlorate | 246.00 µg/L | — | Above Goal |
Lead (90th percentile) | 0.007 mg/L | 0.015 mg/L | Above Goal |
EPA Violation History
No violations in the past 5 years
This system has a clean compliance history.
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
JEFFERSON COUNTY PWSD 1
Population Served
21,113
Water Source
Purchased Surface Water
System ID
MO6024292
JEFFERSON COUNTY PWSD 3
Population Served
17,000
Water Source
Purchased Surface Water
System ID
MO6024294
Frequently Asked Questions About Arnold Water
Is Arnold tap water safe to drink?
Arnold, Missouri tap water receives a grade of A (97/100), which is considered excellent. Out of 69 contaminants tested, none exceed EPA maximum contaminant levels (MCLs) and 2 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 Arnold's water?
Of the 69 contaminants tested in Arnold's water supply, the most notable include Lead (90th percentile), chlorate. No contaminants exceed EPA legal limits. 2 contaminant(s) exceed EPA health goals (MCLGs), which are non-enforceable targets set at levels with no known health risk.
Does Arnold have any water quality violations?
Yes, Arnold has 2 EPA violation(s) on record, with the most recent in 2006. Violation types include Other, MR. None of these are classified as health-based violations.
Do I need a water filter in Arnold?
Arnold water meets EPA standards, so a filter is not strictly necessary. However, some residents prefer the added security of a water filter. EPA health goals (MCLGs) are stricter than legal limits and are set at levels with zero expected health risk. 2 contaminant(s) exceed these stricter goals.
Where does Arnold's tap water come from?
Arnold's drinking water is sourced from purchased surface water and supplied by JEFFERSON COUNTY PWSD 1 and 1 other water system(s). The system serves approximately 38,113 people. Surface water sources include rivers, lakes, and reservoirs.
How often is Arnold'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. Arnold'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 Arnold's water compare to other cities in Missouri?
Arnold's water quality score of 97/100 earns a grade of A, which is considered excellent. This places Arnold among the better-performing water systems in Missouri. Visit our Missouri state page to see how all cities in the state compare.
What should I do if I'm concerned about Arnold's water quality?
If you have concerns about Arnold'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 (JEFFERSON COUNTY PWSD 1) 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.