How to Find Out What Is in Your Water: Consumer Confidence Reports and Private Well Testing

Path 1: Municipal water - reading your CCR

The Consumer Confidence Report Rule (40 CFR 141 Subpart O) requires every community water system in the U.S. to mail an annual water quality report to its customers by July 1 each year. The report covers the prior calendar year's monitoring data. If you have lost the paper version (it is often delivered as an insert in your water bill), you can search for it online through EPA's CCR search tool.

What sections appear in every CCR

• Utility identification: Name, contact information, public water system identification number (PWS ID).
• Source(s): Where your water comes from. Surface water (river, reservoir), groundwater (wells), or purchased from another utility. Many utilities use multiple sources and blend.
• Source water assessment: A summary of risks to the source watershed.
• Detected contaminants table: The core of the report. Each contaminant detected during monitoring is listed with its measured concentration, the EPA MCL or Action Level, the EPA MCLG, the units of measure, and any violations during the reporting period.
• Violations and corrective actions: Any reported violation of an MCL, MRDL, or treatment technique requirement during the year, plus the corrective action taken.
• Educational language: Required EPA boilerplate explaining contaminant categories and high-risk populations.
• Lead-specific notification: Required text on lead, the home plumbing exposure pathway, and tap-flushing recommendations.

How to read the detected-contaminants table

The table is the most information-dense part of the CCR. For each detected contaminant, focus on three columns:

The measured concentration. Utilities typically report the highest level detected during the year and an annual average. The highest level matters more if the contaminant has chronic-exposure health implications; the average matters more for general comparison.

The EPA MCL or Action Level. The legal threshold. Detected concentrations below this meet the law.

The EPA MCLG. The health-based goal. For carcinogens and acute toxicants, MCLG is often zero or much lower than the MCL. Detected concentrations between MCLG and MCL meet the law but indicate a contaminant present below the goal. This is where personal risk tolerance enters.

A common misreading is to assume that "below MCL" means "safe." It means "below the legally enforceable threshold." For lead, arsenic, PFAS, and several DBPs, the MCLG is below the MCL, indicating residual health concern even at concentrations the utility is meeting.

What the CCR does not tell you

CCRs report regulated contaminants the utility is required to monitor. Several limitations apply:

• PFAS may not yet appear. Utilities are completing initial PFAS monitoring under EPA's 2024 rule with a 2027 deadline; reports for 2027 and later should include results.
• Lead in your home is not measured. The CCR reports utility-side lead monitoring (Action Level compliance). Lead from your own service line and plumbing requires household sampling.
• Unregulated contaminants may not appear. Microplastics, certain pharmaceuticals, and some emerging compounds are not on the regulated list and are not required reporting.
• Distribution-system variability. CCR data is usually averaged across multiple sample points. Your specific neighborhood may have different DBP concentrations or chloramine residual than the system average.

Path 2: Private well water - the CDC testing protocol

Private wells serving fewer than 25 people are not covered by EPA's Safe Drinking Water Act. There is no federal requirement to test, no federally mandated sampling schedule, and no automatic notification when contamination occurs. The CDC fills this gap with its Drinking Water Guidelines for Testing Well Water.

Annual baseline tests (CDC recommendation)

CDC recommends every private well be tested annually for four parameters at minimum:

• Total coliform bacteria: Indicator of contamination pathway from surface or shallow groundwater.
• Nitrate (as nitrate-nitrogen): Agricultural runoff or septic indicator. EPA MCL: 10 mg/L. Critical for households with infants under six months.
• Total dissolved solids (TDS): General mineral content. Elevated TDS may indicate saltwater intrusion, road salt contamination, or industrial impact.
• pH: Below 6.5 or above 8.5 may indicate corrosion concerns or naturally aggressive water that leaches metals from plumbing.

Regional add-on tests (CDC and state DOH)

• Arsenic: Recommended in much of the western U.S., Upper Midwest, and Northeast. Some state DOH agencies set state notification levels below the federal MCL of 10 ppb.
• Radon: Recommended in regions with elevated radon-in-water concentration (Northeast, Rocky Mountain states). Different from radon-in-air testing.
• Pesticides: Recommended where the well is downhill from agricultural use or near pesticide handling.
• Fluoride: Some aquifers naturally contain elevated fluoride. EPA MCL: 4.0 mg/L (health), Secondary MCL: 2.0 mg/L (aesthetic, dental fluorosis).
• Iron and manganese: Almost universal in private wells; affects taste and treatment selection.
• Hardness: Determines softener requirement.
• PFAS: Increasingly recommended near AFFF source areas, industrial discharge, and known PFAS hotspots.
• Lead: Recommended for homes with copper plumbing and lead solder, particularly in older homes.

Triggers for additional testing

Beyond the annual baseline, CDC recommends additional testing in specific circumstances:

• Construction or rehabilitation of the well
• Visible changes in water taste, odour, or colour
• Flooding or other potential contamination event
• Family illness suspected to be water-related
• Pregnancy or infants in the household (specifically test nitrate, lead, bacteria)
• Replacing or repairing pump, casing, or piping
• Septic system installation or repair on the property

Where to find a state-certified laboratory

Compliance-grade water testing requires a state-certified laboratory, often called a Certified Environmental Testing Laboratory or a State Drinking Water Laboratory. Three resources cover most of the U.S.:

• EPA Drinking Water Laboratory Certification Program: maintains a directory of state primacy programs that certify drinking water labs. Search for "EPA drinking water lab certification" plus your state.
• Your state Department of Health: usually publishes a list of certified labs that accept private samples. Some state labs accept samples directly; others route through certified private labs.
• Cooperative Extension Services: many state extension programs offer subsidised water testing for residents, particularly for nitrate and bacteria.

Cost varies. Basic baseline tests (coliform, nitrate, TDS, pH) typically range from low to moderate; comprehensive panels including metals, VOCs, and PFAS cost more. Specific dollar figures depend on your state and lab; we do not quote prices because they vary by region and by lab.

EPA action thresholds (selected contaminants)

Related: Lead testing, Coliform and nitrate, Well water guide.