Indicator
Annual Average PM10 Concentration
2023 Evaluation
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PM10 describes inhalable particles, with diameters that are generally 10 micrometers and smaller. This indicator measures the annual average PM10 concentration. Small particulate matter can lodge in the lungs and cause or aggravate the effects of asthma, lung diseases, and heart disease. Elevated concentrations of PM10 can reduce regional visibility and are associated with increased regional haze. The primary sources of PM10 in the Tahoe Basin are motor vehicle emissions, paved and unpaved road dust, wood smoke, wildfire smoke, and construction dust. PM10 is monitored by TRPA and partners at three sites around the Basin. 

Annual Average Pm10 Concentration.jpg
Status

3 year rolling annual average PM10 in the Tahoe Region. 

Data provided by the Desert Research Institute. Access detailed datasets on Tahoe Open Data, including:: Air Quality Station Location Data. Daily Monitoring Data. Yearly Average Data.

2023 Evaluation
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Status
Considerably Better Than Target
Trend
Moderate Improvement
Confidence
Moderate
Applicable Standard
AQ10: Particulate Matter10 Annual Arithmetic Average - Maintain Particulate Matter10 at or below annual arithmetic average of 20µg/m3 in the portion of the Region within California, and maintain Particulate Matter10 at or below annual arithmetic average of 50µg/m3 in the portion of the Region within Nevada. Particulate Matter10 measurements shall be made using gravimetric or beta attenuation methods or any equivalent procedure which can be shown to provide equivalent results at or near the level of air quality standard.
Key Points
  • Annual average PM10 concentrations have shown a long-term improvement, but peak concentrations of particulate matter have increased in recent years due to wildfires.
  • Average PM10 concentrations are well within air quality standards (20 µg/m3 California, 50 µg/m3 Nevada)
  • Reductions in particulate matter on the South Shore can mostly be attributed to reductions in local sources such as increased street sweeping and improving the efficiency of residential wood burning stoves.
  • Particulate matter concentrations at DL Bliss show more steady levels over time. Because particulate matter at DL Bliss comes more from regional sources rather than local sources, regional sources of particulate matter appear to be relatively steady over time.
  • The best scenario for air quality on a local, regional, and national scale is the restoration of the natural fire cycle through prescribed fire or managing natural ignitions when conditions are favorable (Schweizer et al. 2019)
Evaluation Map
Description

The location of air quality monitoring stations in the Lake Tahoe Basin. PM10 is monitored by TRPA and partners at three sites around the Basin.

About the Threshold
This indicator measures the annual average concentration of particulate matter less than or equal to 10 microns in size (PM10). In high concentrations this pollutant can lodge in the lungs and cause or aggravate the effects of asthma, lung diseases, and heart disease. Federal and state standards have been adopted to protect the public from this pollutant.
Particulate matter pollution consists of very small liquid and solid particles in the air. The primary sources of PM10 in the Lake Tahoe Region are motor vehicles, paved and unpaved road dust, wood smoke, and construction dust. The ambient concentration of PM10 is dependent on meteorological conditions such as wind speed and atmospheric mixing.
Delivering and Measuring Success

EIP Action Priorities

  • Build and Enhance Trail Networks

    Bicycling, walking, and other forms of active transportation are important methods of travel that promote healthy lifestyles, improve air quality.

  • Build and Enhance Transit Systems

    Comprehensive and coordinated bus and shuttle transit system that provides seamless around the lake service.

  • Implement Prescribed Fire

    Prescribed fire and fire used for ecological benefit can reduce smoke exposure from large high intensity fires.

  • Reduce Hazardous Fuels

    Reduce hazardous fuels and proactively manage forests to improve ecosystem resilience and reduce wildfire smoke.

EIP Indicators

Example EIP Projects

Local and Regional Plans

Monitoring Programs

Rationale Details
Considerably Better Than Target. The status is determined on the average of the 3-year site averages for the monitoring period 2020-2023 across all monitoring locations. The average reading is 10.2 ppm, 51% of the allowable value or 20 µg/m3. Therefore, the current status is considerably better than target.
Moderate Improvement. Trend was determined using the annual average reading at various South Lake Tahoe sites from 1989-2023 using the Theil-Sen robust regression method. An annual decrease of -1.6% was observed during the time frame. Therefore, a trend of moderate improvement was determined.
Confidence Details
High. Monitoring was conducted using strict protocols to collect a long-term, high quality dataset.
Low. Confidence of trend is based on the coefficient of determination and t-test significance. R²=0.2249 (low), p-value= 0.000029.
Moderate. If one confidence rating is high and the other is low, the overall confidence rating is moderate.
Additional Figures and Resources

No photos available.

No documents available.