How to Read Your Phoenix Water Quality Report: A CCR Explainer for Homeowners

Every Phoenix and Mesa homeowner receives an annual Consumer Confidence Report from their water utility. The City of Phoenix mails it each July, and the City of Mesa publishes it online at mesaaz.gov under its Water Resources section. Most households recycle it without reading it. That is a missed opportunity. The CCR is the only document your utility is legally required to produce that discloses every contaminant detected in your tap water, the method used to measure it, the testing frequency, the EPA maximum contaminant level, and what the utility must tell you if levels exceeded that limit. This guide walks through each section of the report in plain language: what the column headers mean, how to find the numbers that matter most for Phoenix area water (hardness, chloramine residuals, haloacetic acids, PFAS, and arsenic), and how to use the Arizona Department of Environmental Quality PFAS monitoring database to supplement what the CCR reports. Verify all current contaminant data at phoenix.gov/waterservices before making treatment decisions for your home.

What is a Consumer Confidence Report and who has to publish one?

The Consumer Confidence Report requirement comes from the 1996 amendments to the Safe Drinking Water Act. Every community water system serving more than 25 people must produce one annually by July 1, covering the prior calendar year's water quality data. Utilities must mail or electronically deliver a copy to every customer account. The report must also be posted publicly online. The Safe Drinking Water Act gives the EPA authority to set minimum content requirements. The Arizona Department of Environmental Quality oversees compliance for Arizona utilities. Non-compliant utilities face mandatory public notification and potential enforcement action.

The CCR is a legal compliance document first. Every number in it was measured in a state-certified laboratory using EPA-approved methods. Results are reported to ADEQ and audited against permitted testing schedules. If a utility detects a contaminant above its maximum contaminant level, the law requires customer notification within 24 hours for acute health risks and within 30 days for other violations. That notification must include the health risk, the contaminant level, and actions customers should take. Missing from most CCRs: the comparison to non-regulatory health guidelines, the EWG benchmarks, and any qualitative assessment of the gap between legal compliance and the most conservative health research. That context is what this guide adds.

How to find and download your Phoenix or Mesa CCR

The City of Phoenix publishes its annual Consumer Confidence Report on the Phoenix Water Services section of the city website at phoenix.gov/waterservices. Phoenix Water serves customers within the city limits and the Ahwatukee Foothills Village area of Phoenix. On that page, search for 'annual water quality report' or 'consumer confidence report.' The most recent annual report typically appears as the first link in a water quality section. The report is a PDF document and covers all Phoenix Water supply zones.

The City of Mesa publishes its CCR at mesaaz.gov. Navigate to the Water Resources or Utilities section and look for the annual water quality report or CCR link. Mesa's report is specific to City of Mesa water customers and covers all measured parameters for the reporting year. Other Phoenix metro utilities publish their own CCR at their respective city websites: chandleraz.gov for Chandler, scottsdaleaz.gov for Scottsdale, tempe.gov for Tempe, peoriaaz.gov for Peoria. If you receive water from a private water company rather than a municipality, your provider is still legally required to produce a CCR and must mail it to you annually. Contact your water provider directly if you have not received it.

What each column header in the CCR contaminant table means

The core of any CCR is a table listing detected contaminants with several columns. Most homeowners skip this table because the abbreviations are unfamiliar. Reading it once, with the terms defined, is the entire skill needed to interpret your report.

• MCL (Maximum Contaminant Level): the legally enforceable limit set by the EPA. Set by weighing public health protection against the cost and feasibility of treatment. Passing MCL compliance means the utility is legally operating within permitted limits, not that the contaminant is absent or at a health-optimal level.
• MCLG (Maximum Contaminant Level Goal): the non-enforceable health target set by EPA from peer-reviewed research alone, without cost-feasibility constraints. For known carcinogens, the MCLG is often zero. When the MCL and MCLG differ significantly, that gap reflects a regulatory compromise between health goals and treatment cost.
• Level Detected: the actual measured level in your supply for the reporting period. Compare this against both the MCL (legal compliance) and the MCLG (health target). A contaminant can be below the MCL while above the MCLG.
• Range: the lowest and highest detections across all sampling locations and dates during the reporting year. Your specific tap may be at either end of the range. The high end of the range is the maximum exposure your supply produced during the year.
• Violation: whether any sample exceeded the MCL. A yes here triggers mandatory notification. Most Phoenix and Mesa CCRs show no violations, meaning all measured contaminants fell below their respective MCLs during the reporting period.
• Units: micrograms per liter (ug/L or mcg/L), milligrams per liter (mg/L), parts per trillion (ppt), and nephelometric turbidity units (NTU) appear in different sections. PFAS data is reported in parts per trillion. HAA5 and TTHMs are in micrograms per liter. Hardness is in mg/L as calcium carbonate. To convert mg/L as CaCO3 to grains per gallon, divide by 17.1.
• MRDL (Maximum Residual Disinfectant Level): the MCL equivalent for disinfectants like chlorine and chloramine, not contaminants. Phoenix and Mesa use chloramine. The MRDL for chloramine is 4 mg/L as chlorine. The CCR reports the measured chloramine residual alongside this limit.

Is Phoenix tap water safe to drink in 2026?

Phoenix Water met all EPA MCLs in the most recent Consumer Confidence Report. By the legal compliance standard, Phoenix tap water is safe. This is the statement the utility is required to make, and it is accurate at the regulatory level. The City of Phoenix Water Services tests hundreds of samples per month across the distribution system and reports all results. No Phoenix CCR in recent years has listed an MCL violation for regulated contaminants.

The more complete answer requires comparing the CCR numbers against the Environmental Working Group health guidelines at ewg.org. EWG guidelines are set from peer-reviewed health literature without cost-feasibility constraints, which means they are often ten to one hundred times more conservative than EPA MCLs for the same contaminant. Several Phoenix water parameters have historically measured above EWG guidelines while remaining within EPA MCLs. The most notable examples are haloacetic acids and total trihalomethanes, which are disinfection byproducts formed when chloramine reacts with organic matter in source water.

For the general adult population with no specific health risk factors, the MCL compliance answer is the relevant reference point. For households with infants, pregnant residents, or immunocompromised individuals, reviewing the EWG comparison alongside the utility CCR provides a fuller picture. For PFAS specifically, current detection levels and their relationship to the April 2024 MCLs of 4 parts per trillion for PFOA and PFOS are in the most recent Phoenix CCR at phoenix.gov/waterservices. Use the most current published report rather than any secondary summary.

The Phoenix CCR numbers that matter most for area homeowners

Hardness is the most impactful water quality characteristic for daily life in Phoenix, even though it is not regulated as a contaminant. The CCR typically reports hardness in mg/L as calcium carbonate. Divide by 17.1 to convert to grains per gallon. Phoenix water averages approximately 300 to 375 mg/L as CaCO3 across distribution zones, translating to roughly 18 to 22 GPG in the southern zones served by SRP-heavy supply and 12 to 18 GPG in central zones with higher CAP proportions. The U.S. Geological Survey classifies water above 180 mg/L as CaCO3 (10.5 GPG) as very hard, documented at water.usgs.gov. Phoenix metro water sits roughly double that threshold across most of the service area.

HAA5 (five haloacetic acids): disinfection byproducts formed when chloramine reacts with naturally occurring organic matter in the Salt River and CAP source water. The EPA MCL for HAA5 is 60 micrograms per liter. Phoenix water has historically measured below this legal limit. The EWG health guideline for HAA5 is significantly more conservative. Current measured levels are in the annual CCR at phoenix.gov/waterservices. A whole-home catalytic carbon block on the main supply line reduces HAA5 at every tap in the house. Standard granular activated carbon, used in most pitcher filters and refrigerator filters, does not reduce HAA5 reliably at residential contact times.

TTHMs (total trihalomethanes): a related group of disinfection byproducts including chloroform. EPA MCL is 80 micrograms per liter. The same gap between MCL and EWG guideline applies, and the same whole-home catalytic carbon treatment addresses it. PFAS monitoring data under EPA's UCMR5 program appears in the CCR now, covering PFOA, PFOS, and several additional PFAS compounds. The EPA finalized enforceable MCLs for PFOA and PFOS at 4 parts per trillion in April 2024 (epa.gov/ccr). Arsenic appears in Phoenix water from natural geology in the Southwest at trace concentrations; current levels are in the annual CCR. Reverse osmosis at the kitchen reduces arsenic and PFAS together at the drinking tap.

What Mesa's Consumer Confidence Report shows and how it compares to Phoenix

The City of Mesa publishes its Consumer Confidence Report annually at mesaaz.gov. Mesa draws from three primary sources: Salt River Project surface water from the Salt and Verde River watersheds, Central Arizona Project deliveries from the Colorado River, and groundwater well backup during summer peak demand periods. Mesa's CCR documents hardness in the 18 to 22 GPG range (approximately 308 to 375 mg/L as CaCO3), consistent with Phoenix's southern distribution zones. Mesa's disinfection method is chloramine, identical to Phoenix Water practice. Disinfection byproducts including HAA5 and TTHMs appear at levels that have passed EPA MCLs in recent reporting periods.

Mesa's PFAS monitoring data is included in its CCR per UCMR5 requirements. The City of Mesa Water Resources Department monitors multiple sampling points across the distribution system. Current measured concentrations and their relationship to the 4 ppt MCL for PFOA and PFOS are in the published CCR at mesaaz.gov. The ADEQ statewide PFAS database at azdeq.gov supplements the Mesa CCR with additional monitoring data from ADEQ-managed sampling locations. Use both sources together for the most complete picture of PFAS levels in Mesa supply.

The practical comparison between Phoenix and Mesa CCR data: both communities show water that is very hard by USGS classification (water.usgs.gov); both use chloramine as the primary residual disinfectant; both document disinfection byproducts at levels that comply with EPA MCLs; both are now subject to UCMR5 PFAS reporting; and both communities show hardness in a range that the Water Quality Association classifies as requiring treatment for full appliance protection and comfort. Mesa's eastern neighborhoods served by groundwater-blended supply zones may test at the upper end of the 18 to 22 GPG hardness range. Verify your specific Mesa address supply zone at mesaaz.gov.

How to use the ADEQ PFAS database to supplement your CCR

The Arizona Department of Environmental Quality maintains a PFAS monitoring database at azdeq.gov/pfas-resources that extends beyond what the annual CCR captures in two important ways. First, the CCR covers only the prior calendar year, published the following July. ADEQ may publish more current monitoring data that postdates the most recent CCR. Second, the ADEQ database can include sampling from locations within a water system that the CCR summarizes as a range but does not break out by sampling site.

To use the ADEQ resource: navigate to azdeq.gov/pfas-resources and locate the public water system PFAS monitoring data section. Filter by water system name (City of Phoenix, City of Mesa, City of Chandler, City of Scottsdale, etc.) to see all recorded PFAS sampling results for that system. The database shows each sampling location, collection date, PFAS compound detected, and the concentration in parts per trillion. Compare these results to the 4 ppt MCL for PFOA and PFOS and the MCLs for PFBS, PFHxS, PFNA, and HFPO-DA that the EPA included in the April 2024 rulemaking at epa.gov/ccr.

The EPA also maintains a searchable UCMR5 monitoring database at epa.gov/ccr where you can look up results by public water system and reporting period. This database covers all utilities required to test under UCMR5, which includes Phoenix and Mesa. If you find that current PFAS levels in the ADEQ or EPA databases differ from the most recently published CCR, the database results may reflect more recent sampling. Contact your utility directly to confirm current treatment status and whether any remediation is in progress at a specific source.

What to do after reading your Consumer Confidence Report

If your CCR shows all contaminants below both MCL and MCLG, and your household has no specific health risk factors, no immediate action is required from a legal-compliance standpoint. Hardness is the practical exception: it is not regulated, but it is documented in the CCR and has direct consequences for appliances, fixtures, and daily water experience in Phoenix metro homes. If the CCR reports hardness above 180 mg/L as CaCO3 (10.5 GPG), which describes essentially all Phoenix and Mesa water supply zones, you are in the USGS very-hard category. The U.S. Department of Energy has estimated that each grain per gallon of hardness reduces water heater efficiency by approximately 1.5 percent (energy.gov). At 20 GPG, that is a 30 percent efficiency reduction accumulating on an untreated water heater.

For PFAS: if current concentrations in your CCR or the ADEQ database are near or above the 4 ppt MCL for PFOA or PFOS, an NSF/ANSI 58-certified reverse osmosis system at the kitchen sink reduces both compounds by 95 percent or more in independent testing. For haloacetic acids and TTHMs: a catalytic carbon whole-home filter addresses these at every tap. For hardness: an ion exchange water softener sized to your specific tap hardness and household daily water use is the appropriate treatment. A confirmed in-home water test at the tap is more accurate than the utility zone average from the CCR, because your reading can differ from the supply zone range depending on distance from the treatment plant and local distribution infrastructure.

If the CCR lists a violation, your utility was required to notify you directly and in writing. If you did not receive notification for a listed violation, contact Phoenix Water Services at phoenix.gov/waterservices or Mesa Water Resources at mesaaz.gov to understand the violation status, the current measured level, any corrective action in progress, and any interim guidance such as boil water advisory or alternative supply recommendation. Violations are rare in large utilities like Phoenix and Mesa, but they do occur at smaller community water systems in rural Arizona, which the ADEQ monitors and lists at azdeq.gov.