[Guest Post x 2] Prescribed Fire and Air Quality in Washoe County

Enjoy this double guest post by Washoe County Health District Air Quality Management Division and the North Lake Tahoe Fire Protection District. They are key partners that work with us throughout the year and we all coordinate with each other for fire, air quality, and weather related concerns. Enjoy!
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Washoe County Health District Air Quality Management Division

The Washoe County Health District Air Quality Management Division  works closely with local Land Managers to conduct Prescribed Fire treatment to our lands. As part of our Smoke Management Program, we have guidelines in place for Land Managers to follow when writing their burn plans, preparing for a prescribed fire, and the day of the burn. Smoke from prescribed fires does not impact our air quality like wildfires do. As discussed in the Wildfire Smoke in Northern Nevada blog post, particulate matter (PM10 and PM2.5) are found in smoke.


As part of the guidelines for prescribed burns, Land Managers are required to follow the daily Burn Code, and cannot burn during a Red Burn Code, which is typically called in the "Unhealthy for Sensitive Groups" range. Smoke from the 2013 and 2014 wildfires reached Air Quality Index levels in the "Unhealthy" range, meaning everyone can be affected by the pollution in the air. The concentrations of particulate matter in these higher AQI ranges due to wildfire smoke is much more harmful than the concentrations of particulate matter from prescribed fires. 

Smoke from prescribed fires, while visible, very rarely impact Washoe County. The worst wildfires we've had in the Truckee Meadows were 8 to 10 times higher in particulate matter concentrations and 6 to 8 times higher than the health standard than the prescribed fire concentrations shown in the chart below. 

Prescribed fire treatment on our lands is a very important factor in reducing the number and intensities of wildfires, therefore preventing major air quality impacts to our community. For a little more detail about prescribed fires see the portion below by North Lake Tahoe Fire Protection District. 


North Lake Tahoe Fire Protection District 

Annually. fire and land managers implement prescribed fire projects throughout their managed land. Each project includes specific goals or objectives, to reduce hazardous fuels and improve natural resource benefits predetermined by land managers. Two common prescribed fire methods are pile and understory (broadcast) burning. Pile burning involves burning slash piles that were created by hand and mechanical slash piling. 

Understory (broadcast) burning involves implementing a light to moderate intensity fire through the surface or ground area of an identified area, to reduce fuel loading, overstock reproduction, and to accomplish natural limbing of lower branches of more mature and desirable trees. Both methods consist of preparing a prescribed burn fire "Burn Plan". 



Why Prescribed Fire? 
After more than 100 years of fire exclusion practices, an ecosystem that requires periodic fire has become unhealthy and extremely hazardous. Trees are stressed by overcrowding, fire-dependent species are disappearing, invasive non-native species are thriving, flammable fuels have built up and become hazardous, and the general public has dramatically increased development and usage within these unhealthy lands. 

What is the result if land managers do nothing? Catastrophic wildfires!!
  • Fires have become more difficult to control and are more damaging, due to higher intensities and faster rates of spread
    • Increasing threat to public and firefighter life and safety
    • High costs associated with damage/loss of infrastructure
    • High costs associated with suppression and rehabilitation efforts
  • Damaging effects on plants and wildlife
  • Damaging effects to watersheds
  • Destructive post fire effects (floods, loss of timber, erosion, vegetation change, etc.)
  • Increased carbon emissions and poor air quality 
What are the benefits of prescribed fire?
Fire in the wildland plays an essential role in the ecosystem. A "non-catastrophic" fire, whether natural or prescribed has many resource benefits. Prescribed fire is the pre-planned controlled application of fire to the land to accomplish specific land management goals and objectives, to achieve numerous benefits. Some of these benefits include but are not limited to: 
  • Provide for firefighter and public safety and minimize loss/damage to infrastructure during catastrophic wildfire events
  • Reduction of hazardous fuels (natural and/or logging debris)
  • Wildlife habitat, grazing, and forage improvement
  • Insect and disease control
  • Aesthetic appearance enhancement
  • Native vegetation and seeding/planting improvement
  • Perpetuate fire-dependent species
  • Watershed protection and improvement
  • Reduces carbon emissions and greenhouse gases
  • Provide training and qualification opportunities to firefighter personnel
What is a Burn Plan, and who implements the burning? 
The Burn Plan is a document created by land managers to help ensure that the objectives of the project are met in a safe and efficient manner during implementation and post burn efforts. Elements within the burn plan include environmental factors, number of resources/equipment needed on site, contingency planning, fire behavior parameters, smoke management, safety/medical plans, permitting/notification requirements, and pre/post burn requirements. All elements within the plan must be met or followed prior to burn implementation. 

Prescribed fire operations are conducted by trained and qualified fire management personnel who have studied and have experience in fire behavior and fire management/leadership techniques. 

What about the smoke? 
Controlling the amount, duration, and where the smoke goes is an essential part of every prescribed fire operation. Prior to any burning land managers look very closely at possible smoke impacts to schools, residents, roadways, and other smoke sensitive sites proximal to the project area. The burn plan is drafted to minimize negative impacts of smoke to such areas. 

However, smoke is a natural byproduct of fire and some amounts are unavoidable during prescribed fire operations. Periodic prescribed burns prevent heavy fuel accumulations that typically would produce larger amounts and longer duration smoke impacts in the event of an uncontrolled wildfire. 





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