Every year, your water utility sends you a document that most people throw away without reading. It’s called a Consumer Confidence Report (CCR), also known as a Water Quality Report, and it’s the single most useful tool for deciding whether you need a water filter — and which type to buy. The CCR tells you exactly what’s in your tap water, how much of each contaminant was detected, and whether any levels exceeded EPA safety limits.
The problem is that CCRs are written in technical language full of abbreviations, units of measurement, and regulatory jargon that makes them hard to interpret. MCL, MCLG, ppb, ppm, mg/L, Action Level — these terms mean specific things, and understanding them is the difference between making an informed filtration decision and guessing.
I’ve read hundreds of water quality reports over the years, and I’m going to walk you through exactly how to find yours, what each section means, which numbers to pay attention to, and what filtration action (if any) your results suggest.
How to Find Your Water Quality Report
If you’re on a public water system (municipal/city water), your utility is required by the EPA under the Safe Drinking Water Act to publish a CCR annually and deliver it to customers by July 1st each year. Here’s how to find yours:
- Check your mail: Many utilities mail a printed copy or include a link in your water bill.
- Visit your utility’s website: Search for “[your city] water quality report” or “[your utility name] CCR.” Most utilities post the current and previous years’ reports online as downloadable PDFs.
- Use the EPA’s tool: The EPA maintains a CCR search tool at epa.gov/ccr where you can find reports by state and water system.
- Call your utility: If you can’t find it online, call your water utility’s customer service number and request a copy.
If you’re a renter and your water bill is included in rent, you’re still entitled to the CCR. Ask your landlord for the water utility name, then search for the report online.
If you’re on a private well, there is no CCR — private wells are not regulated by the EPA or covered by the Safe Drinking Water Act. You’ll need to get your water tested independently (more on that below).
Understanding the Key Terms
Before you can interpret the numbers in your CCR, you need to understand the terminology:
MCL (Maximum Contaminant Level)
The highest level of a contaminant that the EPA allows in drinking water. MCLs are legally enforceable standards. If your water exceeds an MCL, your utility is in violation and must take corrective action and notify customers. MCLs are set as close to the MCLG as feasible using the best available treatment technology.
MCLG (Maximum Contaminant Level Goal)
The level of a contaminant below which there is no known or expected health risk. MCLGs are non-enforceable health goals — they represent the ideal, not the legal requirement. For carcinogens, the MCLG is often set at zero, even though the MCL (the enforceable limit) may be higher because achieving zero isn’t technically feasible.
Action Level
Used for lead and copper specifically. The Action Level for lead is 15 ppb — if more than 10% of tested homes exceed this level, the utility must take action (corrosion control, public notification, lead service line replacement). Note: the MCLG for lead is zero. There is no safe level of lead in drinking water.
Units of Measurement
- ppm (parts per million): Equivalent to mg/L (milligrams per liter). Used for more common contaminants at higher concentrations.
- ppb (parts per billion): Equivalent to µg/L (micrograms per liter). Used for contaminants at very low concentrations. 1 ppm = 1,000 ppb.
- ppt (parts per trillion): Equivalent to ng/L (nanograms per liter). Used for PFAS and other ultra-trace contaminants. 1 ppb = 1,000 ppt.
- pCi/L (picocuries per liter): Used for radioactive contaminants like radium and radon.
- NTU (Nephelometric Turbidity Units): Measures water cloudiness/turbidity.
Detected Level vs. Range
Your CCR may report contaminant levels as a single average value or as a range (lowest to highest detected across all sampling points). Pay attention to the highest value in the range — that represents the worst-case scenario at some point in your distribution system.
The Contaminants That Matter Most
Your CCR will list dozens of tested contaminants. Here are the ones worth paying closest attention to, along with what filtration addresses each one:
Lead
MCL: Action Level of 15 ppb (MCLG: 0)
Why it matters: Lead causes neurological damage, especially in children. There is no safe level. Lead typically enters water from your home’s plumbing — lead service lines, lead solder on copper pipes, or brass fixtures — not from the utility’s treatment plant. Your CCR shows system-wide lead testing results, but your home’s lead level may differ.
What to do: If your CCR shows lead detections, or if your home was built before 1986 (when lead solder was banned), consider a home water test for lead at your tap. Filter with an under-sink carbon block (NSF 53 certified for lead) or reverse osmosis system.
PFAS (Per- and Polyfluoroalkyl Substances)
MCL: EPA finalized MCLs in 2024 — 4 ppt for PFOA and PFOS individually, with additional limits for other PFAS compounds.
Why it matters: PFAS are “forever chemicals” linked to cancer, thyroid disease, immune system effects, and reproductive issues. They’re found in water supplies near military bases, airports, industrial sites, and areas where firefighting foam was used.
What to do: If PFAS are detected in your CCR at any level, consider an under-sink RO system (95-99% PFAS removal) or a carbon filter certified to NSF P473 for PFAS reduction.
Disinfection Byproducts (TTHMs and HAA5)
MCL: TTHMs: 80 ppb. HAA5: 60 ppb.
Why it matters: When chlorine reacts with organic matter in water, it creates trihalomethanes (TTHMs) and haloacetic acids (HAA5). Long-term exposure is linked to increased cancer risk. These are among the most commonly detected contaminants in municipal water.
What to do: Activated carbon filters (under-sink or whole house) effectively reduce TTHMs and HAA5. RO systems also remove them.
Chlorine/Chloramine
MCL: Chlorine: 4 ppm. Chloramine: 4 ppm.
Why it matters: Used as disinfectants — they’re intentionally added to kill pathogens. At regulated levels, they’re not a health concern, but they affect taste and odor. Some people are sensitive to chlorine/chloramine in shower water (skin and hair dryness).
What to do: Any activated carbon filter removes chlorine. For chloramine, you need catalytic carbon (standard carbon is less effective against chloramine). Check your CCR to see which disinfectant your utility uses.
Nitrates
MCL: 10 ppm
Why it matters: Common in agricultural areas from fertilizer runoff. Dangerous for infants (causes “blue baby syndrome”). Carbon filters do not remove nitrates — you need reverse osmosis or ion exchange.
What to do: If nitrates are detected above 5 ppm, consider an RO system for drinking water, especially if infants or pregnant women are in the household.
Arsenic
MCL: 10 ppb (MCLG: 0)
Why it matters: Naturally occurring in groundwater in many regions. Long-term exposure linked to cancer, cardiovascular disease, and diabetes. More common in well water but also found in some municipal supplies.
What to do: RO systems remove 95-99% of arsenic. Some specialty adsorptive media filters also target arsenic. Standard carbon filters do not effectively remove arsenic.
Reading the Numbers: A Practical Example
Let’s say your CCR shows the following results:
15 ppb | 0 | No |<br /> | Nitrate | 2.1 ppm | 10 ppm | 10 ppm | No |<br /> | PFOA | 2.8 ppt | 4 ppt | 0 | No |<br /> | PFOS | 1.5 ppt | 4 ppt | 0 | No |<br /> | Fluoride | 0.7 ppm | 4 ppm | 4 ppm | No |<br />
No violations — everything is below the MCL. But that doesn’t mean there’s nothing to address:
- Chlorine at 1.2 ppm: Legal and safe, but likely noticeable in taste and shower water. A whole house carbon filter or even a pitcher filter would improve taste significantly.
- TTHMs at 52 ppb: Below the 80 ppb MCL but above the MCLG of 0. The MCLG of zero means there’s no known safe level — any reduction is beneficial. A carbon filter reduces TTHMs effectively.
- Lead at 8 ppb (90th percentile): Below the 15 ppb Action Level, but the MCLG for lead is 0. Eight ppb is not trivial, especially for households with children. An under-sink filter certified to NSF 53 for lead, or an RO system, would reduce this further.
- PFOA at 2.8 ppt: Below the 4 ppt MCL but detectable. Given the MCLG of 0 and the emerging research on PFAS health effects, filtering PFAS from drinking water is prudent. An RO system or NSF P473-certified carbon filter addresses this.
- Fluoride at 0.7 ppm: This is the level many utilities target for dental health benefits. If you want to reduce fluoride, you’ll need RO or a specialty fluoride filter — standard carbon doesn’t remove fluoride.
Based on this example report, a reasonable filtration strategy would be: a whole house carbon filter for chlorine taste throughout the home, plus an under-sink RO system for drinking water to address lead, PFAS, TTHMs, and provide the deepest purification at the tap.
What Your CCR Doesn’t Tell You
CCRs have important limitations:
- Lead from your plumbing: The CCR reports system-wide lead testing, not your specific home. Lead enters water from your home’s pipes and fixtures. If your home was built before 1986, a home water test at your tap is essential.
- Contaminants not tested: The EPA regulates approximately 90 contaminants, but there are thousands of potential contaminants in water. Emerging contaminants like microplastics, many pharmaceuticals, and some PFAS compounds may not appear in your CCR because they’re not yet regulated.
- Conditions between the plant and your tap: Water quality can change as it travels through the distribution system. Aging pipes, water main breaks, and seasonal variations can affect what reaches your faucet.
- Private well water: If you’re on a private well, there is no CCR. You’re responsible for testing your own water. The EPA recommends annual testing for bacteria, nitrates, pH, and TDS at minimum.
When to Get a Home Water Test
A home water test analyzes the water at your specific tap, catching contaminants that the CCR might miss. Consider a home test if:
- Your home was built before 1986 (lead solder risk)
- You’re on a private well (no CCR available)
- Your CCR shows detectable levels of concerning contaminants
- You notice changes in taste, odor, or appearance
- You’re pregnant, have infants, or have immunocompromised household members
- You want to verify that your current filter is working
Companies like Tap Score and SimpleLab offer mail-in test kits ($100-$400 depending on the panel) that provide detailed analysis of your tap water. Local certified labs also offer testing, often at lower cost for specific contaminants. Your state’s health department can recommend certified labs in your area.
Frequently Asked Questions
Is my water safe if there are no violations in the CCR?
No violations means your water meets EPA legal standards — which is a good baseline. However, “legal” doesn’t always mean “optimal.” Many contaminants have MCLGs of zero (meaning no level is considered completely safe), while the enforceable MCLs are set higher based on treatment feasibility. Additionally, the CCR doesn’t test for every possible contaminant. No violations is reassuring, but it doesn’t mean your water is contaminant-free.
How often is my water tested?
Testing frequency varies by contaminant and water system size. Large systems test for bacteria daily, lead and copper every 6-12 months, and many chemical contaminants annually or every 3 years. Some contaminants are tested only every 6-9 years. Your CCR will note the testing period for each contaminant listed.
What if my CCR shows a violation?
Your utility is required to notify you of any violations and explain what corrective actions are being taken. In the meantime, consider using a water filter appropriate for the specific contaminant that exceeded the MCL. For acute violations (bacteria, nitrates), follow any boil-water advisories immediately.
Can I trust my CCR?
CCRs are based on regulated testing by certified laboratories, and utilities face significant penalties for falsifying data. The data is generally reliable. However, the CCR represents system-wide averages and may not reflect conditions at your specific tap. A home water test provides the most accurate picture of what you’re actually drinking.
The Bottom Line
Your water quality report is a free, valuable tool that most people ignore. Find it, read it, and use it to make informed decisions about water filtration. Focus on the contaminants with MCLGs of zero (lead, TTHMs, HAA5, PFAS) — even if detected levels are below the MCL, reducing exposure is beneficial. And if your home has risk factors (old plumbing, well water, proximity to industrial sites), supplement the CCR with a home water test for the most complete picture.
The 15 minutes it takes to read your CCR can save you hundreds of dollars by helping you choose the right filter — or confirming that you don’t need one at all.
Related articles:
- Water Filter Buying Guide — complete guide to choosing the right filter
- NSF Certifications Explained — understanding filter certification standards
- Best Water Filters for PFAS — if your CCR shows PFAS
- Best Water Filters for Lead — if lead is detected
- Well Water Treatment Guide — for private well owners