Is Your Drinking
Water Safe?
Search water quality data for 433K water systems serving 346.8M Americans. Real EPA data. Plain language results.
National Overview
Source: EPA Safe Drinking Water Information System (SDWIS)
Water Systems
433,347
Across all states & territories
People Served
346.8M
Total population with access
Lead Violations
4,894
Systems exceeding action level
Copper Violations
0
Lead & Copper Rule violations
States With Most Lead Violations
Water systems exceeding the EPA action level of 15 ppb
Pennsylvania
22,622 water systems
vs. EPA action level (15 ppb)
North Carolina
23,923 water systems
vs. EPA action level (15 ppb)
New Hampshire
4,131 water systems
vs. EPA action level (15 ppb)
New Jersey
14,932 water systems
vs. EPA action level (15 ppb)
Ohio
16,365 water systems
vs. EPA action level (15 ppb)
Michigan
27,019 water systems
vs. EPA action level (15 ppb)
Common Water Contaminants
Learn about health effects, sources, and how to reduce exposure
Lead
heavy metal
Developmental delays in children, kidney problems, high blood pressure. No safe level of lead exposure for children.
Action Level: 0.015 mg/L
Copper
heavy metal
Short-term: gastrointestinal distress. Long-term: liver or kidney damage. People with Wilson's disease are more sensitive.
MCL: 1.3 mg/L
Arsenic
metalloid
Increased risk of cancer (skin, bladder, lung). Thickening and discoloration of skin; numbness; circulatory problems.
MCL: 0.01 mg/L
Nitrate
inorganic
Infants below 6 months can develop methemoglobinemia ('blue baby syndrome'). May also affect adults with certain conditions.
MCL: 10 mg/L
PFAS (Per- and Polyfluoroalkyl Substances)
emerging contaminant
Increased risk of certain cancers, immune system effects, thyroid hormone disruption, high cholesterol, reproductive effects.
MCL: 0.000004 mg/L
Chlorine
disinfectant
Eye/nose irritation, stomach discomfort at high levels. At MCL levels, not expected to cause health effects.
MCL: 4 mg/L
Elevated Average Lead Levels
These areas show higher-than-typical average lead concentrations.
Frequently Asked Questions
Common questions about drinking water safety, contaminants, and EPA standards.
Is my tap water safe to drink?+
For most Americans, yes. The Safe Drinking Water Act requires public water systems to meet EPA standards and report violations. Safety varies by location and infrastructure age. Search your water system on SafeWater to see current violations, contaminant levels, and any outstanding compliance issues.
What are PFAS and why are they concerning?+
PFAS (per- and polyfluoroalkyl substances) are a group of thousands of synthetic chemicals used in nonstick cookware, firefighting foam, and food packaging. They are called 'forever chemicals' because they do not break down in the environment or the human body. Long-term exposure is linked to cancer, thyroid disease, and immune system effects. In April 2024, the EPA set enforceable limits for six PFAS in drinking water for the first time.
What is the EPA limit for lead in drinking water?+
The EPA's Lead and Copper Rule sets an action level of 15 parts per billion (ppb). If more than 10% of samples exceed this, systems must take action. The EPA has stated there is no safe level of lead exposure. The agency proposed a new rule in 2023 to lower the action level to 10 ppb and require lead pipe replacement within 10 years.
How do I check my water quality report?+
By law, all public water systems must publish an annual Consumer Confidence Report (CCR) by July 1st each year. You can search your water system by state on SafeWater to see contaminant data, violation history, and EPA compliance records. You can also request a copy of your CCR directly from your utility.
What are the most common drinking water contaminants?+
The most prevalent contaminants found in U.S. water systems include: lead (from aging pipes), nitrates (from agricultural runoff), disinfection byproducts like trihalomethanes (from chlorination), arsenic (naturally occurring), coliform bacteria (indicating sewage contamination), and PFAS from industrial sources. Contaminant risk varies greatly by geography and infrastructure age.
What water filter removes the most contaminants?+
Reverse osmosis (RO) systems have the broadest removal range, covering lead, arsenic, nitrates, PFAS, and most bacteria. Activated carbon filters (like Brita) remove chlorine, VOCs, and some heavy metals but do not remove nitrates or PFAS. NSF/ANSI certification indicates a filter has been independently tested for the contaminants it claims to remove.
Know What's in Your Water
Search by state or browse contaminant guides. All data comes directly from the EPA. We just make it easier to understand.
Data: EPA Safe Drinking Water Information System · Not a substitute for official Consumer Confidence Reports