Centennial, Colorado

Environmental Quality Report Card

Centennial reports good air quality, with AQI levels better than the national average. Water tests indicate concerning conditions across key measures. Facility compliance with environmental standards is below the national average.

Air Quality (Annual Overview)

Grade A
24.9 AQI

Yearly average AQI (2024): 24.9. National average: 41.4. 23 moderate days, 0 unhealthy days recorded.

Water Quality (Key Indicators)

Grade N/A
8.7 pH

Latest pH level (2024): 8.7. Ideal range: 6.5–8.5.

Facility Violations

Grade C
14 significant violations

Facilities like factories and treatment plants had 14 significant and 2604 total violations reported in 2024.

Water Quality (with EPA Standards)

Water quality measurements are provided by the Water Quality Portal , a collaboration between the USGS, EPA, and other agencies.

Characteristic Local Value Safe Range Grade Last Measured
pH 8.70 6.5 - 8.5 C 9/25/2024

Water Quality (No EPA Standard)

These measurements do not have formal EPA standards but are still important indicators of local water quality.

Characteristic Local Value Unit Last Measured
Temperature, water 16.30 deg C 9/25/2024
Escherichia coli 365.40 #/100mL 9/25/2024
Dissolved oxygen (DO) 9.56 mg/L 9/25/2024
Specific conductance 608.00 uS/cm 9/25/2024
Total microcystins plus nodularins 17.10 ug/L 7/22/2024

Air Quality Details (2024–2025)

The Air Quality Index (AQI) measures how clean or polluted the air is. A lower AQI means cleaner air. Main pollutants include particulate matter like PM2.5, ozone, and others regulated by EPA standards.
Air quality data sourced from OpenAQ, aggregating official monitoring stations.

Yearly Average AQI National Average AQI Good Days Moderate Days Unhealthy Days Worst Day AQI Top Pollutant
24.9 41.4 342 23 0 90 (on 7/22/2024) PM2.5

Monthly AQI Trend

Monthly average AQI values over the past year. Lower values are better. Peaks may indicate pollution events.

Facility Compliance

Facility compliance and violation data come from the EPA's ECHO database.

5,000+ monitored facilities

Total Violations: 2604

Significant Violations: 14

Total Penalties: $2,840,266

Despite 14 significant violations, Centennial reported 2,604 total violations across monitored facilities in 2024. This results in a compliance grade of C, reflecting average adherence to environmental standards compared to national benchmarks.

About the Data

This report uses the latest publicly available environmental data:

  • Air Quality: Data sourced from the OpenAQ Platform, aggregating official air quality monitoring stations near Centennial.
  • Water Quality: Measurements from the Water Quality Portal, a collaboration between the USGS, EPA, and other agencies.
  • Facility Compliance: Sourced from the EPA's ECHO Database, detailing facility violations, penalties, and compliance rates.

All data is refreshed regularly and reflects the latest available figures for 2024.