Greeley, Colorado

Environmental Quality Report Card

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

Air Quality (Annual Overview)

Grade A
28.1 AQI

Yearly average AQI (2024): 28.1. National average: 41.4. 44 moderate days, 0 unhealthy days recorded.

Water Quality (Key Indicators)

Grade B
8 pH

Latest pH level (2024): 8. Ideal range: 6.5–8.5.

Facility Violations

Grade C
26 significant violations

Facilities like factories and treatment plants had 26 significant and 3051 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
Arsenic 0.70 mg/L <0.01 F 12/8/2024
Copper 1.00 mg/L <1.3 A 12/8/2024
pH 8.00 6.5 - 8.5 A 12/8/2024
Mercury 0.00 mg/L <0.002 A 6/19/2024
Lead 0.00 mg/L <0.015 A 12/8/2024
Zinc 7.53 mg/L <5 F 12/8/2024

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
Fluoride 0.53 mg/L 12/8/2024
Uranium-238 14.20 ug/L 12/8/2024
Organic carbon 5.50 mg/L 12/8/2024
Nickel 6.91 ug/L 12/8/2024
Dissolved oxygen (DO) 12.05 mg/L 12/8/2024
Chloride 42.80 mg/L 12/8/2024
Selenium 4.10 ug/L 12/8/2024
Sulfate 323.00 mg/L 12/8/2024
Total Nitrogen, mixed forms 4.87 mg/L 12/8/2024
Specific conductance 1344.30 uS/cm 12/8/2024
Temperature, water 4.73 deg C 12/8/2024
Nitrate + Nitrite 4.04 mg/L 12/8/2024
Hardness, Ca, Mg 431.00 mg/L 12/8/2024
Iron 239.00 ug/L 12/8/2024
Total Phosphorus, mixed forms 1.70 mg/L 12/8/2024
Manganese 55.60 ug/L 12/8/2024
Alkalinity, total 210.00 mg/L 12/8/2024
Ammonia-nitrogen 0.23 mg/L 12/8/2024
Aluminum 148.00 ug/L 12/8/2024
Chromium 12.90 ug/L 11/4/2024
Sodium 89.40 mg/L 12/8/2024
Calcium 116.00 mg/L 12/8/2024
Potassium 12.80 mg/L 12/8/2024
Magnesium 44.70 mg/L 12/8/2024
Escherichia coli 86.20 #/100mL 10/23/2024
Molybdenum 2.70 ug/L 12/8/2024

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
28.1 41.4 321 44 0 82 (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: 3051

Significant Violations: 26

Total Penalties: $15,898,559

Despite 26 significant violations, Greeley reported 3,051 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 Greeley.
  • 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.