Park City Wildfire Risk Assessment
Project Goal: Evaluate the risk of wildfire around Park City, Utah and plan next steps to mitigate that risk
Park City Wildfire Risk Assessment
Welcome to Park City, Utah, home of the largest ski resort in the United States and 9,000 happy residents. Located in the Wasatch Range, Park City is surrounded by forested hillslopes that have the potential for extreme fire behavior that could affect resident property, lives, and livelihoods.
Wildfire in Utah.
Wildfire continues to grow as a threat throughout the American West and the state of Utah. “Utah is one of the most wildfire prone states in the U.S. There are 800 to 1,000 wildfires in Utah annually.” (Source). The five largest wildfires have all occurred in the last 20 years, causing billions of dollars of property destruction.
While wildfire hasn’t directly impacted the Park City area, in 2021 the Parley’s Canyon fire ignited just a few miles away. With a changing climate, wildfire risk continues to be a threat to the community.
Parley's Canyon Fire, 2021.
Wildfires affect much more than trees and homes. While the flames are a primary concern, that is just the tip of the iceberg. There are many other factors to look at, such as smoke, community preparedness, avalanches and flooding.
To better understand the level and impact of wildfire risk, the Park City Municipal Corporation engaged a team of four consultants: Alpine Forestry , Blue Mountain Environmental Consulting , The Ember Alliance , and Sageland Collaborative . The Park City Community Wildfire Risk Assessment is a comprehensive assessment of community resources and locations at an elevated risk of a wildfire. The project looked at:
Wildfire risk assessments are like icebergs: Fire risk and behavior is just the visible part and many other effects are not seen.
- Fire-Adapted Communities - Emergency Preparedness - Avalanche Terrain - Current Stream Health - Post-Fire Flooding - Wildfire Behavior and Hazards
Project Area
Map of the Project Area for the Park City Wildfire Risk Assessment.
Frequently Asked Questions
When will I be able to provide input?
Community input was gathered through surveys and meetings between July and December 2022. Follow the project on Engage Park City to find out when meetings are coming up.
Who is this project for, and who will it affect?
This project is for anyone who lives, works, and owns property within the project area, as shown in the map above. The assessment will outline a plan that brings agencies, major landowners, districts, and residents together to mitigate the risk of wildfire in the area. Homeowners, business owners, employees, government agencies, and contractors will all have a role to play in mitigating risk when this assessment is complete.
Why is this project necessary in Park City?
Wildfires in the western United States are getting larger and more severe. These fires are affecting communities that live in the wildland-urban interface (WUI) by burning homes and tourism infrastructure, forcing evacuations, and negatively affecting air and water quality and wildlife habitat. Fire is a natural part of the ecosystems in Park City, but they have been suppressed and excluded for over a century. The fuels that used to burn in small, frequent fires have built up and can cause dangerous fire conditions.
Climate change is also changing the precipitation and weather that affects how fires behave and how firefighters can manage them. Climate change means summers are on average 2.5 degrees warmer, and fires are becoming larger and more destructive. This project aims to evaluate where and how fires will burn in the Park City area and will outline steps for homeowners, major landowners, and the City to take to mitigate the risk of extreme fires.
Fire Adapted Communities
Community knowledge and adaptation is an important aspect of wildfire risk.
Fire Adapted Communities work together to reduce the impact of wildfires in their community. They accomplish this through mitigation work, prevention and education, planning, and preparing for recovery.
Park City can become a Fire Adapted Community if everyone works together to navigate shared barriers. A survey was conducted as part of this project to identify barriers and opportunities for the community.
Fire Adapted Communities Activity Wheel
Community Engagement Survey
The survey measured current perspectives and knowledge of the community regarding wildfire and emergency preparedness. It focused on what the community is most concerned about and what needs they felt were most important.
Over 400 people participated in the survey and nearly 300 provided personal comment. 75% of survey respondents were primary homeowners, 25% were secondary.
Knowledge Gaps: A majority of respondents indicated they are lacking the knowledge to take effective wildfire mitigation steps. An overwhelming majority (62%) indicated the single thing they would find most helpful was having a wildfire mitigation assessment done at their property.
“I do not know what slash piles are. There should be a 'don’t know' option!” - Park City Resident
The biggest concerns around wildfire for respondents were:
- Air Quality (89%) - Wildlife Habitat (87%) - Water Quality/Concerns (85%) - Loss of life was rated as a priority by only 74% of respondents.
“It's totally not clear to me what old town residents can do for wildlife mitigation when we have no land/ trees and live within arms reach of neighbors.” - Park City Resident
Resources for Education: Respondents listed the three organizations as their go to source for education and information about wildfire:
Park City Fire Department Wildland Engine
Financial Investment: A major obstacle to effective action beyond lack of knowledge was financial costs, with 59% saying they were only willing to spend $1,000-$2,000 annually. Many wildfire mitigation projects are inexpensive and simple to do, but some can cost thousands of dollars for things like tree removal or replacing a roof.
“I would love a clear ordinance to provide clear, concise guidance to Park City residents about what they need to do to protect their homes from wildfires.” - Park City Resident
Stakeholders: Residents look to stakeholders for transparency demonstrating they are doing their part towards wildfire mitigation and making the community safer. This includes the City, ski resorts, and other major organizations in the area.
Stakeholder land in Park City, including the ski resorts and city parks.
Emergency Preparedness
Wildfire behavior and consequences can be altered by community preparedness actions.
Are we ready for when a fire comes?
Throughout the community survey, respondents noted concerns about emergency preparedness, particularly relating to evacuations. A minority of residents said they had signed up for notification or practiced an evacuation. Many noted concerns about evacuating and egress routes.
“I live in Old Town and I am very concerned about access of fire, medical and police resources and egress of residents and visitors during a fire in and around Old Town.” - Park City Resident
The community survey indicated:
- Only 49% of respondents to the survey have evacuation plans for their home and family.
- A mere 7% have practiced evacuating their home within 15 minutes or less.
- Only 28% have go-bags at the ready.
“Would buses be deployed to evacuate neighborhoods?” - Park City Resident
Values and Resources
What do we need to protect?
Assessing the community values and resources is a critical part of the Community Wildfire Risk Assessment. These values are things in and around the community that residents care about, and they can be both natural resources or human-made assets.
The values that were selected for this project were similar to other assessments in the intermountain west, as well as additional ones defined by local stakeholders. These are defined before conducting fire behavior modeling to see which values are at the greatest risk.
Values are ranked by relative importance in order to better look at how they interact with fire. The relative importance is on a scale of 1-100 (1 being Least Important and 100 being Most Important). Park City has many values to protect through mitigation, and you can tour some of these below:
Park City and the surrounding area has many values that are at risk if a wildfire comes through. Values are things that are important to and support the community. They can include things like open spaces, wildlife habitat, communication towers, ski resorts, or water infrastructure.
These values are mapped against the predicted wildfire behavior to see their relative risk to wildfire. This can help the community make choices about where to mitigate first.
Avalanche Terrain
Wildfires and fuels treatments can affect avalanche terrain, and vice versa.
Why are we looking at avalanches?
Situated in a mountain environment where winters are notorious for prolific snowfall, the community of Park City is home to an abundance of steep slopes and the associated hazards of snow avalanches. One of the most important factors in reducing the avalanche hazard around Park City is robust forest and vegetation coverage. Forests can offer protection from avalanches through several processes, most notably by trees providing anchoring stability for the snow and their ability to reduce temperature swings that can affect avalanche behavior. Changes to the forests, either from wildfire or forest management, can impact the frequency and size of avalanche events.
“Resorts should help with glading efforts to offer better and safer skiing, which will in turn offload fuel concerns.” - Park City Resident
As part of this wildfire risk assessment, avalanche areas were identified and mapped under current forest and vegetation conditions. This data will help forest managers manage the risks of wildfire while minimizing changes to existing risk of snow avalanches.
Examples of avalanche mapping and photos of avalanche terrain near Park City.
Current Stream Health
Wildfires and watersheds are closely linked processes.
Why do we look at stream health?
The health of Park City’s watersheds is valuable to the function of the region’s water resources and the humans and wildlife that rely on them. Mud and debris flows after wildfires erode wetlands, wash away vegetation, impact water quality, and degrade wildlife habitat. A healthy, functioning stream ecosystem can be more resilient to high intensity wildfires. This stream health assessment focused on the condition of a selection of stream resources in and around the project area.
“I think our water quality is important as is the danger a fire in the Deer Valley area.” - Park City Resident
Use the arrow to the right to explore stream health in the Park City area. Click on a purple stream section on the map to learn more about it's scoring.
Each different category was ranked from 1-5, with 5 meaning excellent quality and 1 being very degraded quality.
Scientists working in the field.
Bloods Lake Drainage
The Bloods Lake Drainage is a relatively small ephemeral stream in the Bonanza Flat Conservation Area. It is currently used for open space, recreation, wildlife habitat, and watershed protection.
The drainage’s overall score was 2.8. Click the stream section to the right for details. This stream channel is eroded and disconnected from the surrounding area. Riparian vegetation showed signs of extensive browsing and grazing from moose and deer; however, the riparian area was heavily vegetated and had high soil integrity.
In the event of a high intensity wildfire, this drainage would likely be severely degraded and impact downstream infrastructure and streams. Managers should be ready to implement best management practices to reduce erosion.
Walker and Webster Canyon
Walker and Webster Canyon is owned and managed by Park City Municipal Corporation and is currently used for open space and recreation. Historically, this site was used for mining activities with mining infrastructures still in place nearby.
It has an overall score of 3.5 due to a well vegetated riparian area and diversity of habitat. Click the stream section to the right for details. Walker and Webster Canyon scored highest for water quality due the section having a lot of shade.
This stream would be more resilient to the impacts of a wildfire because it contains structure from existing vegetation and debris that can mitigate mud and debris flows. However, the canyon is relatively narrow and steep. The drainage could move significant sediment into downstream waters, should a high intensity wildfire occur. It feeds into urban portions of Park City via Silver Creek and there is increased risk of infrastructure being negatively impacted.
Thaynes Canyon
Thaynes Canyon is a perennial stream owned and managed by Park City Municipal Corporation and is currently used for open space and recreation. Historically, this site was used for mining and grazing, but currently shows little signs of disturbance.
The overall score was 3.6 as a result of good vegetation and habitat diversity. Click the stream section to the right for details. Thaynes Canyon scored highest for water quality because of shade and a lack of filamentous algae.
This stream would be relatively resilient to wildfire because it is has structure from vegetation and woody debris that can mitigate mud and debris flows. However, a high intensity wildfire in this steep area could significantly affect Thaynes Canyon, the residences below the canyon, and water resources downstream.
McLeod Creek
McLeod Creek is a perennial stream managed by the Utah Division of Wildlife Resources as wildlife habitat. The area was used agriculturally and the nearby uplands are still used for cattle grazing.
Much of McLeod Creek’s water supply is diverted for irrigation, creating low flow conditions. The overall score was 3.6. Click the stream section to the right for details. This area scored high for water quality due to shade and a lack of filamentous algae. It has high canopy cover of good riparian species like willow. Bonneville cutthroat trout are known to occur here.
Beaver reside here and their damming activity can mitigate floods. The creek’s vegetated riparian corridor can serve as a firebreak for active wildfires. This area is also the focus of restoration efforts. With management and further restoration, McLeod Creek may be more resilient to the impacts of a high intensity wildfire.
Silver Creek
Silver Creek is an intermittent stream owned and managed by Snyderville Basin Special Recreation District and is currently used for grazing, open space, and recreation. Private landowners use property above and below the reach for grazing. An irrigation canal runs to the east of the stream, contributing to low flow. It is listed as an Impaired Water area for game fish and aquatic life due to dissolved cadmium and zinc from contaminated from mine tailings upstream.
Silver Creek’s overall score was 2.5. Click the stream section to the right for details. During floods, the adjacent wetlands can dissipate floodwaters. Despite it’s impairment, the site contains important wetland habitat for wildlife. A northern leopard frog was observed and this reach is potential habitat for Ute ladies’-tresses orchid, a federally Threatened species.
A wildfire in the adjacent uplands or in the watershed could further disperse contaminated soils into Silver Creek and the Weber River.
Northern Leapord Frog seen at the stream site
Kimball Creek
Kimball Creek is managed by Utah State University’s Swaner Preserve and EcoCenter as open space, historically used as agricultural land.
This creek’s overall score was 3.4. Click the stream section to the right for details. It has high phosphorus levels and low dissolved oxygen, creating degraded conditions of aquatic life. Much of the water supply is diverted for irrigation.
This area has been the focus of restoration efforts. Techniques like adding structure to the stream, or beaver mimicry, are collecting sediment and allowing the floodwaters to dissipate over the adjacent floodplain wetlands. This increases resiliency in the event of a wildfire.
Tributary to Willow Creek
This tributary flows into Willow Creek, Kimball Creek, and East Canyon Creek. The stream area is managed by Utah State University’s Swaner Preserve and EcoCenter as open space. This stream was likely modified for irrigation. Upstream has been altered by residential development.
The tributary is part of one of the largest wetland complexes in the Project area, so it sequesters carbon and provides clean water. This reach’s overall score was 3.0. Click the stream section to the right for details. This reach scored low for water quality and terrestrial habitat because of the presence of algae and lack of vegetation cover. This reach is the focus of restoration efforts by local stakeholders.
East Canyon Creek
East Canyon Creek is a main tributary in the Weber River and is managed by Snyderville Basin Special Recreation District and Summit County as open space. It was used as grazing land for cattle and sheep previously, and is surrounded by residential and commercial development.
It's overall score was 2.6. This reach had low scores for water quality because of an abundance of filamentous algae and lack of vegetation and shade. East Canyon would be expected to have more tree cover, but these species have not recovered from past grazing activity.
While this creek is degraded, the stream is valued by the community. The impacts of a nearby wildfire could lead to significant loss of ecosystem function and services. The East Canyon Watershed Committee are working on education, restoration, and policy.
Post-Fire Flooding
Fires and flooding often happen in close sequence.
Why do we look at post-fire flooding and erosion?
The impacts of wildfires do not end once the flames extinguish.
- Intense rainfall events can result in flash floods, erosion, and debris flows the first few years following a wildfire.
- Debris flows are fast-moving landslides that begin without warning. They are one of the most dangerous post-fire hazards because they can be life threatening, move rapidly, and strike with little warning
- Drinking water quality was impacted by the Dollar Ridge Fire and triggered a $28.5 million project to update the Duchesne County Water Treatment Plant. Sediment and ash also decimated the brown trout population in the Wild Strawberry River—a Blue Ribbon Fishery.
“We have lived through fires and mudslides post fire, it is no joke. The community must be educated on risk and planning.” - Park City Resident
Parleys Canyon Fire
Aug 14-21, 2021, 158 acres
East Vivian Fire
July 26-Aug 11, 2000, 1,753 acres
Dollar Ridge Fire
July 1-30, 2018, 57,897 acres
Coal Hollow Fire
Aug 4-Sep 6, 2018, 29,912 acres
Pole Creek Fire
Sept 6-Oct 7, 2018, 103,545 acres
Seeley Fire
June 26-July 18, 2012, 48,050 acres
Parleys Canyon Fire
Aug 14-21, 2021, 158 acres
52% of the soil in the area was moderately to severely burned. Thunderstorms on August 18, 2021, caused a flash flood and deposited debris within 75 feet of Interstate 80.
Source: (Turner, 2021)
East Vivian Fire
July 26-Aug 11, 2000, 1,753 acres
60% of the soil in the area was moderately to severely burned. Intense thunderstorms on August 31, 2000, produced flooding and debris flows down the South Fork Provo River and into properties in Vivian Park.
Source: (Gecy, 2000; Pope, 2002)
Dollar Ridge Fire
July 1-30, 2018, 57,897 acres
31% of the soil in this fire area experienced moderate to high burn severity. Thunderstorms on July 22, 2018, triggered debris flows and sedimentation that damaged homes, roads, bridges and fisheries. About 50 people needed to be rescued in Duchesne County after becoming trapped by floodwaters.
Drinking water quality was impacted and triggered a $28.5 million project to update the Duchesne County Water Treatment Plant. Sediment and ash also decimated the brown trout population in the Wild Strawberry River—a Blue Ribbon Fishery.
Source: (Canham, 2018; Central Utah Water Conservancy District, 2021; Hardy, 2018; Murray, 2019)
Coal Hollow Fire
Aug 4-Sep 6, 2018, 29,912 acres
63% of the burned area had moderate to high soil burn severity. Thunderstorms on August 12 and 13, 2022, caused flooding and debris flows at Mill Fork and Dairy Fork in Spanish Fork Canyon and triggered the need for debris removal by UT County Public Works.
See videos of flooding at Mill Fork: https://www.youtube.com/watch?v=I-BZXFXVle8
Source: (Burt, 2022; Natharius & Meccariello, 2018)
Pole Creek Fire
Sept 6-Oct 7, 2018, 103,545 acres
45% of the soil in the burned area was moderately to severely burned. Flooding on August 8, 2019, damaged US Highway 89 and 4 miles of US Highway 6, where about 3-5 feet of debris were deposited. Flooding triggered evacuations of residents in Loafer Canyon and damaged at least a dozen homes. Sediment impacted the quality and quantity of irrigation water provided by Strawberry Water Users Association to farms near Payson, UT.
Source: (Hardy, 2018; Harris, 2022; Roberts, 2019)
Seeley Fire
June 26-July 18, 2012, 48,050 acres
45% of the area's soil was moderately to severely burned. Intense rainfall and flooding occurred on July 7, 16, 30 and 31, 2012, and September 1, 2012, and July 16 and 19, 2013.
Flooding and debris flow on July 7, 2012, caused serious damage to State Route 31, powerlines, coal mines, trails and recreation sites. Sediment buried the Huntington/Cleveland Irrigation Company’s headgate and clogged sprinkler lines. Debris flows in Huntington Creek caused PacifiCorp-Huntington Power Plant to shut their water intake for several days. Impacts to water quality were observed as far as 50 miles downstream. Fish died in the Price and San Rafael rivers due to ash-clogged gills, including endangered razorback suckers.
Source: (Chatel, 2012; Giraud & McDonald, 2013)
“Education, more publicity for recommended alternative plants, and assistance in how to transition landscaping to attractive drought- and fire-resistant designs would be very helpful.” - Park City Resident
Forests to Faucets Drinking Water Importance Index for Utah. Source: USFS)
What is at Risk?
Homes and Businesses
About 1,560 homes and businesses in the area (12% of all addresses) are in watersheds with a high risk of damage from post-fire erosion and debris. Homes and businesses with high risk of post-fire sediment delivery are located in or around Quarry Mountain, White Pine Canyon, Iron Canyon, Thaynes Canyon, McLeod Creek at the base of Crescent Ridge, Walker and Webster Gulch, Empire Canyon, Rossi Hill, Bald Eagle Mountain, and north of Deer Valley Meadow.
Critical Infrastructure
Water infrastructure in the area has a high risk of damaging post-fire sediment. The high risk of streams and other water infrastructure to post-fire sediment delivery is particularly concerning given the importance of watersheds in this part of Utah for the delivery of clean drinking water.
Wildfire Behavior and Hazards
Forests, topography, weather, and other factors are known to affect wildfire behavior.
What is a QWRA?
A Quantitative Wildfire Risk Assessment (QWRA) is a process where a community looks at the important values in their area and sees what kind of fire behavior might be expected near them.
Conducting QWRA can make land management decisions more effective by identifying the predicted benefits and threats from fire on several, values across the Park City landscape.
This information can be used to plan fuel treatments, plan suppression response, design fire effects monitoring programs and other related management activities on a landscape while accounting for the predicted benefits and threats from fire and the relative importance of different landscape values
What Steps are in This Process?
Simulate Wildfire
Landscape Burn Probability quantifies the relative likelihood and intensity of a fire occurring on a simulated summer day.
Example of wildfire simulation outputs. This map shows expected flame lengths in the study area.
Example of data from wildfire simulation and analysis
Map Values
These HVRAs are the community values that were discussed earlier.
Exposure Analysis
This analysis overlays the Landscape Burn Probability model outputs with the community values to see which ones are most exposed to wildfire.
Risk Assessment
QWRA represents both losses and benefits resulting from fire and takes into account:
- How often fire occurs (likelihood)
- The intensity when a fire occurs (intensity)
- The effects of fire on HVRAs (susceptibility) & their importance (importance)
The three inputs to a QWRA
Relative importance was determined by the results of the community survey and by local stakeholders.
Phase 3 will include actions and resources based on the entire assessment.
