A81/100
Cottonwood Tap Water Quality: Is It Safe to Drink? (2026 Report)
Serving 6,645 residents · California
What's In Cottonwood's Tap Water?
27
Contaminants Tested
0
Exceed EPA Limits
0
Above EPA Goals
EPA Violation History
No violations in the past 5 years
Full EPA compliance since 2015.
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
COTTONWOOD WATER DISTRICT
Population Served
3,316
Water Source
Groundwater
System ID
CA4510007
RIO ALTO WATER DISTRICT
Population Served
3,329
Water Source
Groundwater
System ID
CA5210005
Frequently Asked Questions About Cottonwood Water
Is Cottonwood tap water safe to drink?
Cottonwood, California tap water receives a grade of A (81/100), which is considered excellent. Out of 51 contaminants tested, none exceed EPA maximum contaminant levels (MCLs) and 1 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 Cottonwood's water?
Of the 51 contaminants tested in Cottonwood's water supply, the most notable include Lead (90th percentile). No contaminants exceed EPA legal limits. 1 contaminant(s) exceed EPA health goals (MCLGs), which are non-enforceable targets set at levels with no known health risk.
Does Cottonwood have any water quality violations?
Yes, Cottonwood has 11 EPA violation(s) on record, with the most recent in 2024. Violation types include RPT, TT, MCL. 6 of these are health-based violations, which are the most serious category.
Do I need a water filter in Cottonwood?
Cottonwood 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. 1 contaminant(s) exceed these stricter goals.
Where does Cottonwood's tap water come from?
Cottonwood's drinking water is sourced from groundwater and supplied by COTTONWOOD WATER DISTRICT and 1 other water system(s). The system serves approximately 6,645 people. Groundwater is pumped from underground aquifers, which often provides natural filtration.
How often is Cottonwood'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. Cottonwood'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 Cottonwood's water compare to other cities in California?
Cottonwood's water quality score of 81/100 earns a grade of A, which is considered excellent. This places Cottonwood 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 Cottonwood's water quality?
If you have concerns about Cottonwood'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 (COTTONWOOD WATER DISTRICT) 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.