Tapcensus

Peoria City of

Community water system in Peoria, Maricopa County, Arizona, serving 187,676 people from surface water. 4 rules violated in the past three years, 1 still unresolved. Owned by local government. System ID AZ0407096.

People served 187,676 surface water
Rules violated, past 3 years 4 one rule can carry several violations
Unresolved 1 rules still in violation, EPA data updated Oct 7, 2026
Quarters with violations 7 of the last 12 quarters

Quarterly compliance history

–Q4
2023
–Q1
2024
VQ2
2024
VQ3
2024
VQ4
2024
VQ1
2025
VQ2
2025
–Q3
2025
–Q4
2025
–Q1
2026
VQ2
2026
VQ3
2026
UQ4
2026
–No violation identified VViolation identified SSerious violator (EPA enforcement priority) UUndetermined Oldest quarter on the left. Quarters 1 to 12 are the twelve most recently completed quarters at EPA's last data refresh; the 13th is the current quarter up to that date, which EPA reports as undetermined.

Still in violation

EPA data updated Oct 7, 2026

Lead and Copper Rule (LCR)

The 1991 LCR uses action levels rather than MCLs: if the 90th percentile of high-risk tap samples exceeds 15 ppb lead or 1.3 mg/L copper, the system must take…
EPA rule code 5000 · Treatment Technique

What it means: The 1991 LCR uses action levels rather than MCLs: if the 90th percentile of high-risk tap samples exceeds 15 ppb lead or 1.3 mg/L copper, the system must take escalating corrective actions. Violations typically indicate failure to maintain adequate corrosion control — the treatment that keeps lead from leaching out of pipes, solder, and fixtures.

Health effects: Lead: no safe level for children. Causes irreversible neurological damage, impaired cognitive development, behavioral problems, and reduced IQ in children under 6. In adults: hypertension, cardiovascular disease, kidney damage. Copper: acute gastrointestinal distress at high levels; liver/kidney damage at very high chronic levels.

Limit: Action levels: lead 15 ppb, copper 1.3 mg/L — 90th percentile of tap samples at high-risk sites

About this rule

Also violated in the past three years

Oct to Dec 2023 to Oct to Dec 2026

Carbon, Total

EPA rule code 2920
EPA rule code 2920 About this rule

Long Term 2 Enhanced Surface Water Treatment Rule (LT2)

The LT2 ESWTR (2006) required all surface water and GWUDI systems to monitor source water for Cryptosporidium, then apply additional treatment based on…
EPA rule code 0800 · Treatment Technique

What it means: The LT2 ESWTR (2006) required all surface water and GWUDI systems to monitor source water for Cryptosporidium, then apply additional treatment based on measured concentrations. Higher-bin systems (more oocysts detected) must install advanced treatment — UV disinfection, ozone, or membrane filtration — beyond the original SWTR requirements.

Health effects: Cryptosporidium is a chlorine-resistant protozoan parasite that causes cryptosporidiosis — severe watery diarrhea, cramping, nausea, and fever. In immunocompromised individuals (HIV/AIDS, transplant recipients), it can be life-threatening and prolonged. Infants and the elderly are also at elevated risk. LT2 violations indicate failure to complete monitoring or apply the required additional treatment tier.

Limit: Treatment technique — additional Cryptosporidium treatment based on bin classification

About this rule

Nitrate

Nitrate (NO₃) is the most common chemical contaminant in US groundwater, entering from fertilizers, septic systems, and animal waste.
EPA rule code 1040 · Inorganic Chemical

What it means: Nitrate (NO₃) is the most common chemical contaminant in US groundwater, entering from fertilizers, septic systems, and animal waste. It is odorless and tasteless — the only way to know if it's present is to test.

Health effects: Methemoglobinemia in infants under 6 months: gut bacteria convert nitrate to nitrite, which blocks oxygen transport in blood. Pregnant women should also take precautions. Chronic adult exposure at elevated levels may increase cancer risk.

Limit: 10 mg/L as nitrogen (NO₃-N)

About this contaminant
About this data

EPA counts the rules a system was in violation of, not the individual violations; one rule can carry several in the same period. Unresolved means still in violation at EPA's latest data refresh. Measured contaminant levels are not part of this record; each system publishes them in its annual Consumer Confidence Report.

Service area from EPA's Public Water System Service Area Boundaries dataset: State Agency. The system's location is the centre of the service area EPA publishes for the system.

Source: the U.S. EPA's Enforcement and Compliance History Online system (ECHO), which publishes the federal Safe Drinking Water Information System. EPA's terms and values are shown as published. The Arizona records are from EPA's data refresh of Oct 7, 2026; EPA refreshes this data quarterly, and states report to EPA with a lag of three to six months, so the newest violations may not appear yet. Retrieved from ECHO on Oct 11, 2026.