Planning for Evacuation: Egress Routes in the Event of Wildfire...

Planning for Evacuation: Egress Routes in the Event of Wildfire for the Community of

Sleepy Hollow, Orinda, California

Prepared for: Radke

Department Landscape Architecture & Environmental Planning 221 University of California, Berkeley

Spring 2014

Prepared by:

May, 2015

Diana Edwards Valerie Francella

Jay Mahabal Kathy Tran

Egress Routes in the Event of Wildfire for the Community of Sleepy Hollow, Orinda, California

i May 2015

Table of Contents1 Introduction ............................................................................................................................ 1

1.1 Sleepy Hollow Elementary School .................................................................................. 3

2 Objective of Study .................................................................................................................. 3

3 Methods ................................................................................................................................. 3

3.1 Input Data ....................................................................................................................... 4

3.2 Fire Modeling and ‘Hot Spot’ Identification ..................................................................... 6

3.2.1 Farsite Modeling ...................................................................................................... 6

3.2.2 Output Processing ................................................................................................... 8

3.2.3 Hot Spot Selection ................................................................................................. 15

3.3 Staging Area Selection ................................................................................................. 17

3.4 Network Analysis .......................................................................................................... 19

3.5 Service Area ................................................................................................................. 19

4 Results ................................................................................................................................. 20

4.1 Hot Spot Results ........................................................................................................... 20

4.2 Sleepy Hollow Elementary Egress Results .................................................................. 23

4.3 Service Area Results .................................................................................................... 26

5 Recommendations and Conclusions .................................................................................. 29

5.1 Further Research .......................................................................................................... 29

6 References .......................................................................................................................... 30

Table of FiguresFigure 1. Regional & Local Location of Study Area ...................................................................... 2 Figure 2. Conceptual Flow Chart of Methods Used for This Study ............................................... 4 Figure 3. Data Used in Study ........................................................................................................ 5 Figure 4. Conceptual Flow Chart Outlining the Methods used in Fire Modeling and “Hot Spot” Identification .................................................................................................................................. 6 Figure 5. Conceptual Flow Chart Outlining the Fire Modeling Process ........................................ 6 Figure 6. Farsite Fire Model: Ignition Points ................................................................................. 7 Figure 7. Fire Model: Time of Arrival ........................................................................................... 10 Figure 8. Fire Model: Heat Per Area ........................................................................................... 11 Figure 9. Fire Model: Flame Length ............................................................................................ 12 Figure 10. Fire Model: Rate of Spread ........................................................................................ 13 Figure 11. Fire Model: Combined Fire Vulnerability .................................................................... 14 Figure 12. Vulnerable Hot Spots in road Network ....................................................................... 16


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Figure 13. Staging Areas for the Sleepy Hollow Neighborhood .................................................. 18 Figure 14. Hot Spots Along the Network that Most Compromise Egress ................................... 21 Figure 15. Closest Staging Area to Sleepy Hollow ..................................................................... 22 Figure 16. Best Egress Route for Sleepy Hollow Elementary if North or West Fire Scenario .... 24 Figure 17. Best Egress Route for Sleepy Hollow Elementary in South or East Fire Scenario .... 25 Figure 18. Five Minute Service Area Impact Analysis ................................................................ 27 Figure 19. Ten Minute Service Area Impact Analysis ................................................................. 28


1 May 2015

1 Introduction Sleepy Hollow is a small, affluent neighborhood tucked in the hills of Orinda (Figure 1). The neighborhood is home to approximately 7,247 residents spread across approximately 2700 acres (US Census 2010). Sleepy hollow is comprised primarily of single family homes, a golf course, a tennis and swim club, and two elementary schools: Sleepy Hollow Elementary School and Wagner Ranch Elementary School. Remoteness, quality schools, large properties, and lush vegetation attract residents. This neighborhood, however, lies within an urban-wildland interface that poses a natural fire hazard for residents. Most of Sleepy Hollow is located in a very high fire hazard severity zone as designated by CAL FIRE (CDFFP 2009). Additionally, there is currently no comprehensive wildfire evacuation plan. The neighborhood could therefore greatly benefit from a comprehensive wildfire emergency plan. Wildfires are a normal part of California’s ecology due to the Mediterranean climate (where summers are hot and dry), natural vegetation, and geography (Wolshon 2007). These factors are accentuated in Sleepy Hollow by the presence of non-native species such as eucalyptus and brushes like juniper, which have combustible oils that burn very hot (Rice 2013). During a site visit on March 14, 2014, it was apparent that this community was surrounded by fire hazards; juniper bushes surrounded many homes and piles of trimmed oak trees littered backyards. The winding, narrow roads of Sleepy Hollow further pose fire hazards. This area has very few major roads that could serve as egress routes. With few options, the obstruction of even one route greatly affects the entire egress operation. There are only four main roads that the neighborhood road network feeds into: Bear Creek Road, Camino Pablo, Lombardy Lane, and Miner Road. Many cars also park along the single car lanes, which would make it difficult for emergency responders to respond efficiently as well as compromise effective egress.


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Figure 1. Regional & Local Location of Study Area


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1.1 Sleepy Hollow Elementary School The Sleepy Hollow school children are one of the most vulnerable populations within this community. In 2013, the Sleepy Hollow Elementary School released an Emergency Preparedness Handbook. The handbook provides preparedness plans for multiple emergency scenarios including earthquakes, explosions, and wildfires. The plan was created by school administrators, the Moraga-Orinda Fire department, Orinda Police department, and the Moraga-Orinda Emergency Preparedness Director. In the event of a wildfire, the Handbook outlines a plan to shelter-in-place at the school. The Handbook states, “The school is well equipped to support the temporary sheltering needs of students and faculty. School grounds are maintained so that they will provide a safe haven for students with their teachers should the school become “cut off” from the community.” Administrators have also designated a footpath behind the school that leads to Bear Creek Road in events that require students to evacuate the classrooms. In effect, congestion would be prevented since parents could pick up their children from a major road rather than driving through the single lane road leading up to the school. These plans are not foolproof, however, since wildfires may ignite nearby the school and expand in unexpected ways.

2 Objective of Study The three objectives of our study included:

1. determining the optimal egress route for Sleepy Hollow Elementary School in the event of a wildfire during school hours;

2. identifying points along the Orinda road network that are most vulnerable to wildfire; and

3. conducting a preliminary analysis of community-wide wildfire egress scenarios.

3 Methods The study area included the Sleepy Hollow Neighborhood and downtown Orinda, and an additional 0.6 mile buffer around these areas (see Figure 1). In order to meet our objectives we employed computerized spatial models and performed several analyses using ArcGis, ArcMap, and ArcCatalog (ESRI, version 10.2.2, 2015) and Farsite (version 4.1.055, 2008). A conceptual flow chart was created in order to outline these steps (Figure 2). The data used and analyses conducted are further outlined in the following section.

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Figure 2

3.1Most of the data used in analyses were derived from the LA221 dataset, found here:http://ced.berkeley.edu/courses/sp13/ldarch221/finalProject/Sleepy_Hollow_Data.htmlThese datasets include layers for the boundary of the Sleepy Hollow Neighborhood, National Land Cover Program (NAIP) imagery at 0.30 meter resolution (2011), and a road network obtained from Uriel Garcia of the Moraga With the high resolution aepools were digitally created by the class.Hollow Elementary School, Orinda Public Library, and Wagner Ranch Elementary School.

Egress Rou

2. Conceptual Flow Chart of Methods

3.1 Input Data Most of the data used in analyses were derived from the LA221 dataset, found here:http://ced.berkeley.edu/courses/sp13/ldarch221/finalProject/Sleepy_Hollow_Data.htmlThese datasets include layers for the boundary of the Sleepy Hollow Neighborhood, National Land Cover Database imagery at 1 meter resolution (2011),Program (NAIP) imagery at 0.30 meter resolution (2011), and a road network obtained from Uriel Garcia of the Moraga

With the high resolution aepools were digitally created by the class.Hollow Elementary School, Orinda Public Library, and Wagner Ranch Elementary School.


Conceptual Flow Chart of Methods

Input Data Most of the data used in analyses were derived from the LA221 dataset, found here:http://ced.berkeley.edu/courses/sp13/ldarch221/finalProject/Sleepy_Hollow_Data.htmlThese datasets include layers for the boundary of the Sleepy Hollow Neighborhood, National

Database imagery at 1 meter resolution (2011),Program (NAIP) imagery at 0.30 meter resolution (2011), and a road network obtained from Uriel Garcia of the Moraga-Orinda Fire Department (Figure 3).

With the high resolution aerial imagery, land cover classifications for buildings, pavement and pools were digitally created by the class.Hollow Elementary School, Orinda Public Library, and Wagner Ranch Elementary School.

tes in the Event of Wildfire for the Community of Sleepy Hollow, Orinda, California

Conceptual Flow Chart of Methods

Most of the data used in analyses were derived from the LA221 dataset, found here:http://ced.berkeley.edu/courses/sp13/ldarch221/finalProject/Sleepy_Hollow_Data.htmlThese datasets include layers for the boundary of the Sleepy Hollow Neighborhood, National

Database imagery at 1 meter resolution (2011),Program (NAIP) imagery at 0.30 meter resolution (2011), and a road network obtained from

Orinda Fire Department (Figure 3).

rial imagery, land cover classifications for buildings, pavement and pools were digitally created by the class. This imagery was also used to manually locate Sleepy Hollow Elementary School, Orinda Public Library, and Wagner Ranch Elementary School.


Conceptual Flow Chart of Methods Used for This Study


Database imagery at 1 meter resolution (2011),Program (NAIP) imagery at 0.30 meter resolution (2011), and a road network obtained from


rial imagery, land cover classifications for buildings, pavement and This imagery was also used to manually locate Sleepy

Hollow Elementary School, Orinda Public Library, and Wagner Ranch Elementary School.


Used for This Study


Database imagery at 1 meter resolution (2011), National Agriculture Imagery Program (NAIP) imagery at 0.30 meter resolution (2011), and a road network obtained from





Used for This Study


National Agriculture Imagery Program (NAIP) imagery at 0.30 meter resolution (2011), and a road network obtained from




Most of the data used in analyses were derived from the LA221 dataset, found here: http://ced.berkeley.edu/courses/sp13/ldarch221/finalProject/Sleepy_Hollow_Data.html These datasets include layers for the boundary of the Sleepy Hollow Neighborhood, National

National Agriculture Imagery Program (NAIP) imagery at 0.30 meter resolution (2011), and a road network obtained from




4

These datasets include layers for the boundary of the Sleepy Hollow Neighborhood, National

Program (NAIP) imagery at 0.30 meter resolution (2011), and a road network obtained from



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Figure 3. Data Used in Study

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3.2Fire modeling and ‘hot spot’ identification was the first step to identify areas most vulnerable to wildfire within the Orinda road network in order to Hollow Elementary School.

Figure 4Spot” Identif

A conceptual flow

Figure 5

Egress Rou

3.2 Fire Modeling and ‘Hot Spot’ IdentificationFire modeling and ‘hot spot’ identification was the first step to identify areas most vulnerable to wildfire within the Orinda road network in order to Hollow Elementary School.

4. Conceptual Flow Chart Outlining the Methods used in Fire Modeling and “Hot Spot” Identification

3.2.1 A conceptual flow-chart of the steps taken to model wildfire can be found in Figure 5.

5. Conceptual Flow Chart Outlining the Fire Modeling Process


Fire Modeling and ‘Hot Spot’ IdentificationFire modeling and ‘hot spot’ identification was the first step to identify areas most vulnerable to wildfire within the Orinda road network in order to Hollow Elementary School. A flow

Conceptual Flow Chart Outlining the Methods used in Fire Modeling and “Hot ication

Farsite Modelingchart of the steps taken to model wildfire can be found in Figure 5.

Conceptual Flow Chart Outlining the Fire Modeling Process


Fire Modeling and ‘Hot Spot’ IdentificationFire modeling and ‘hot spot’ identification was the first step to identify areas most vulnerable to wildfire within the Orinda road network in order to

A flow-chart outlining this process can be found in Figure 4.

Conceptual Flow Chart Outlining the Methods used in Fire Modeling and “Hot

Farsite Modeling chart of the steps taken to model wildfire can be found in Figure 5.



Fire Modeling and ‘Hot Spot’ IdentificationFire modeling and ‘hot spot’ identification was the first step to identify areas most vulnerable to wildfire within the Orinda road network in order to develop optimal egress routes for Sleepy

chart outlining this process can be found in Figure 4.


chart of the steps taken to model wildfire can be found in Figure 5.



Fire Modeling and ‘Hot Spot’ Identification Fire modeling and ‘hot spot’ identification was the first step to identify areas most vulnerable to

develop optimal egress routes for Sleepy chart outlining this process can be found in Figure 4.





Fire modeling and ‘hot spot’ identification was the first step to identify areas most vulnerable to develop optimal egress routes for Sleepy











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Figure 6. Farsite Fire Model: Ignition Points


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Four computerized fire models were run with Farsite (version 4.1.055, 2008) to simulate various wildfire scenarios (Figure 6). Model inputs included: landscape, weather, wind, spread rate adjustments, and initial fuel moisture. The landscape file included elevation, slope, aspect, fuel model, and canopy cover specific to Sleepy Hollow. The remaining model inputs were derived from a class dataset of conditions for the 1991 fire in Claremont Canyon. Claremont Canyon conditions are proxy for Sleepy Hollow conditions since it is also located in a canyon. Model parameters were left at the default and fire burns were simulated for 24 hours between 10/22 and 10/23. Fires were arbitrarily initiated in the four cardinal directions of north, east, south and west to capture fire characteristics that may occur if a fire were to start in a general area. Initiation areas mostly had fuel sources that were shrub and grass since they burn quickly and easily. Four model outputs were captured to describe the burn characteristics of the four fire models within Sleepy Hollow and to select hot spots. The outputs were in raster grid format and the resolution of all output files were 10 meters by 10 meters. Time of arrival, in elapsed minutes, depicted how far the burn reached within 24 hours (Figure 7). Flame length (FML) showed how high the flames burned in feet. Heat per unit area (HPA), in BTU/ft2, captured how hot areas burned. Lastly, rate of spread (ROS) indicated how fast the fire spread through Sleepy Hollow. These four outputs were considered as the most important burn characteristics to selecting hot spots since they would likely influence the speed and feasibility of egress routes.

3.2.2 Output Processing To simplify our analysis, all outputs were processed except the time of arrival since temporal effects were not considered here. They were processed so the values of each parameter could be translated into categories and weights. Processing involved first classifying the values of each output into 5 categories determined by quantiles so that each bin had about an equivalent number of areas that fall into each category. Refer to Table 1 for the value ranges of each output and fire simulation. Overall, the values for FML ranged between 0 feet and 101 feet, with the highest value coming from the North fire. The values of the HPA ranged between 8 and 62, 792 BTU/feet2, with the highest value coming from the East fire. The values for the ROS ranged between 0 and 350 feet/minute, with the highest value coming from the North fire.

Flame Length (ft) Heat per Area (BTU/ft2)

Rate of Spread (ft/min)

North Fire 0 - 101 8 - 43,388 0 - 350

East Fire 0 - 97 10 - 62,790 0 - 233

South Fire 0 - 86 9 - 33, 729 0 - 183

West Fire 0 - 92 8 - 47,285 0 - 275

Table 1. Ranges of Farsite Output Results


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After reclassification, the raster grid files were converted to polygons in order to add weights for a “hot spot” analysis. Weights corresponded to the five arbitrary categories. Weights ranged from 1 to 5, with 1 being the lowest values and 5 being the highest values of FML, HPA, and ROS. Refer to Figures 8-10 for visualizations of the categorized outputs. The layers for individual FML, HPA, and ROS were then unionized for each of the four fire models to produce an overall weight across all outputs. The overall weights were generated by summing the weights for FML, HPA, and ROS. The overall score ranged between 3 and 15. Three indicated that all three fire characteristics had weights of 1 and 15 indicated that all three fire characteristics had weights of 5. All values in between indicated that the fire characteristics had varying classifications (Figure 11).


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Figure 7. Fire Model: Time of Arrival


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Figure 8. Fire Model: Heat Per Area


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Figure 9. Fire Model: Flame Length


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Figure 10. Fire Model: Rate of Spread


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Figure 11. Fire Model: Combined Fire Vulnerability


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3.2.3 Hot Spot Selection Hot spots were defined as having high flame length, high rate of spread, high heat per area, and proximity to the roads. The overall weights ranged from 13-15 and the number of areas falling into these categories ranged between 350 and 2000. The overall weights used for each fire model were as follows: 14-15 for the North fire, 15 for the East fire, 15 for the South fire, 13-14 for the West fire. Three to four hot spots were lastly selected based on their proximity to roads. Points were created for each hot spot. In the North fire, hot two hot spots lie on Bear Creek Road and one on Tappan Lane. In the East fire, hot spots lie on Miner Road, Oak Flat Hill Drive, and Tiger Tail Court. In the South fire, hot spots lie on Via Floreado, La Espiral, La Cuesta, and the intersection of Via Farallon and Mira Loma. In the West fire, two major hot spots lie on Bear Creek Road and one on Manzanita Drive (Figure 12).


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Figure 12. Vulnerable Hot Spots in road Network


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3.3 Staging Area Selection Staging areas were first assessed through a Location Allocation analysis using the Sleepy Hollow Network. Nodes on the network were proxies for resident homes, and staging area candidates were selected through manual identification of institutions in the area. The first analysis revealed the Orinda Country Club to be the most ideal candidate based on its location. Upon further research, it was discovered that the Country Club does not provide much shelter and amenities, so it is not an optimal location for housing local residents for extended periods of time. Additionally, the Moraga-Orinda Fire Department has already designated a staging location with stocked supplies in case of community emergencies (Personal communication with Dennis Rein, MOFD). The final, and community recognized and designated, primary staging area selected for this project is the Orinda Public Library. Residents are currently aware that it is their local community emergency center. It is located en-route to the 24 Freeway as residents egress from Sleepy Hollow, making it an excellent spot for residents to obtain emergency information. The library is also close to the BART Station, which provides an alternative mode of transit out of Sleepy Hollow for residents. A secondary staging area is Wagner Ranch Elementary School. Wagner Ranch is located on Camino Pablo, a main road, which provides residents quick access to other main roads and an alternative shelter to the library. Both staging areas currently have emergency resources (Figure 13).


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Figure 13. Staging Areas for the Sleepy Hollow Neighborhood


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3.4 Network Analysis Once staging areas and hot spots were identified, optimal egress routes were determined with the ArcMap network analysis tool. The network, acquired from Uriel Garcia, was modified in ArcCatalog to include the footpath to Bear Creek Road from Sleepy Hollow Elementary School, which was included in the network analysis. A “Closest Facility” analysis was first performed without barriers to understand the length of time it would take to drive from Sleepy Hollow Elementary to the Orinda Public Library and Wagner Ranch Elementary. The staging area that could be accessed within the shortest amount of time without impedance was considered the “Closest Facility.” To simulate weekday conditions during school hours, the start time selected was a Tuesday at 1:00 PM. Hot spots were then added as barriers to the network to run a “Best Route” analysis from Sleepy Hollow to the two staging areas. Tuesday, 1:00 PM was also input as the start time. Since the northern and western hot spots were located in close proximity and/or overlapped, they were grouped together for the this analysis, and southern and eastern hot spots were also grouped together. The output of the analysis was three maps (see Results section), the first map showed the fastest route from Sleepy Hollow Elementary School to one of the two staging areas. The other maps showed the fastest routes between Sleepy Hollow Elementary and one of the two staging areas when the network was compromised by hot spots. Limitations of this approach were that the analysis did not account for traffic congestion or road construction along the network.

3.5 Service Area A ‘Service Area’ network analysis was conducted in order to meet our objective of conducting a preliminary analysis of community-wide wildfire egress scenarios. A ‘Service Area’ analysis consists of using the ArcMap network analysis tool called “Service Area” to identify areas, served by the road network that can be evacuated in a certain time period. For this analysis, service areas that were five- and ten-minute drive time from the Orinda Public Library at 2:00pm on a Thursday were assessed. A service area analysis, for both the five- and ten- minute scenarios, without any barriers in the network was initially conducted. Once this unimpeded service area was established, four additional analyses were conducted, for both the five- and ten- minute scenario, each with the hot spots as barriers in the network. The purpose of this analysis was to find out which areas within the Sleepy Hollow neighborhood would be affected the most by barriers in the egress network if a fire were to occur in the neighborhood. Just as with the first network analysis, some of the limitations of this analysis are that traffic congestion, road construction, or other hazards (other than hot spots) that may impair the network were not considered.


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4 Results Results of our analyses included the following: 1. hot spots within the Sleepy Hollow study boundary for different ignition scenarios; 2. most vulnerable locations along the network to impedance by fire or smoke; 3. best routes for egress from Sleepy Hollow Elementary to staging areas depending on the

ignition point; and 4. areas of the Sleepy Hollow Community most likely to have compromised access to

staging areas in different ignition scenarios.

4.1 Hot Spot Results Overall, the hot spots identified do not significantly compromise major thoroughfares and the egress network within Sleepy Hollow. The North and West fire simulations resulted in hot spots with most potential impact since these hot spots lie on Bear Creek road. Not only are the hot spots near the footpath for Sleepy Hollow Elementary School’s egress route, but they also can block routes for emergency responders. Based on the fire simulations, Sleepy Hollow Elementary is most vulnerable if fires were to start from either the west or north. While hot spots identified in the south and east fire simulations do not impact major roads, they do suggest that residents will face challenges when they escape from their homes. Not only does the surrounding vegetation pose hazards, but the windy, narrow roads will also likely impede people from escaping their neighborhoods. Figure 14 shows areas along the network that may most compromise egress. Fire trucks indicate locations where pre-emptive clearing could occur or where the network should be defended in case of fire. The hot spots identified provide an incomplete picture of the fire hazard potentials in Sleepy Hollow. The simulations only capture fire characteristics initiated in four arbitrary points and with extreme meteorological conditions from the 1991 Claremont Canyon fire. Hot spots were also identified based on fire characteristics within 24 hours as opposed to intervals within that span of time. Hot spots would likely differ depending on the hour after an ignition.


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Figure 14. Hot Spots Along the Network that Most Compromise Egress


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Figure 15. Closest Staging Area to Sleepy Hollow


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4.2 Sleepy Hollow Elementary Egress Results Without any barriers in the network, both the Orinda Public Library and Wagner Ranch are nearly equidistant from Sleepy Hollow Elementary. Orinda Public Library is slightly closer by a margin of approximately one tenth of a minute (5.9 minutes vs. 5.8 minutes), and the quickest route from Sleepy Hollow Elementary to the Orinda Public Library is via Miner Road (Figure 15). When hot spots for the fires that ignite in the north or west of Sleepy Hollow are considered, the closest facility and fastest route remain the same. In these scenarios, Bear Creek Road and the footpath from Sleepy Hollow Elementary would likely to be compromised (Figure 16). However, if ignition occurs in the east or south of Sleepy Hollow, the footpath to Bear Creek Road becomes the more favorable egress route as Miner Road may become compromised (Figure 17). In this case, students should be staged at Wagner Ranch Elementary as opposed to Orinda Public Library. Should the fire continue to spread and impact Highway 24, students can then be evacuated down San Pablo Dam Road to Highway 4, which is adjacent to the San Pablo reservoir, and is reasonably well shielded from fire.


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Figure 16. Best Egress Route for Sleepy Hollow Elementary if North or West Fire Scenario


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Figure 17. Best Egress Route for Sleepy Hollow Elementary in South or East Fire Scenario


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4.3 Service Area Results The results of the service area analysis are presented in Figures 18 and 19. Through this analysis we were able to determine the areas where egress would be most impacted by hot spots. In the five-minute service area we found that the North, West, and South fire scenarios impacted the service area. However, the East fire scenario did not impact the 5-minutes service area. This may be due to the fact that the East fire hot spots are located at the edge of the 5-minute service area. In both the North and West fire scenarios, portions of Bear Creek Road were impacted by hot spots, and thus increase the amount of time needed to egress from those locations. Similarly, the South fire hot spots impacted the amount of time that egress would take from central Sleepy Hollow to the Orinda Public Library. The results of the ten-minute service area analysis also found portions of Bear Creek Road were impacted by both the North and West fire scenarios. In contrast, however, the South fire and East fire scenarios did not impact the 10-minute service area. This analysis is a very preliminary look at the most at-risk locations within the study area, further study that include better traffic congestion modeling will give a better idea of how the network could be impacted by wildfire.


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Figure 18. Five Minute Service Area Impact Analysis


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Figure 19. Ten Minute Service Area Impact Analysis


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5 Recommendations and Conclusions Results indicate that the Orinda Public Library remains the best staging area for Sleepy Hollow Elementary and the community as a whole under most circumstances. The size of the facilities and close proximity to Highway 24 allow for quick egress from Orinda if the blaze were to become unmanageable. In addition, while hot spots exist in close proximity to Miner Road, they do not directly affect this route. Nevertheless, in cases where the fire ignites or spreads from the eastern or southern corners of Sleepy Hollow, Miner Road may become compromised by smoke, intense heat or spotting from nearby hot spots. In these cases, the footpath from Sleepy Hollow Elementary to Bear Creek Road and subsequent staging at Wagner Ranch Elementary is the safer and faster option. These results suggest that there is a need for a dynamic egress strategy for the students of Sleepy Hollow Elementary. Depending on the direction from which the fire ignites, an official from the fire department should notify the school of the optimal egress, sheltering or staging strategy. For instance, while shelter-in-place is a feasible option for eastern and southern igniting fires, this is not recommended for northern and western ignition scenarios due to the close proximity of the school to several hot spots. In addition, the fire department and/or the community may wish to undertake proactive measures to defend the road network. Ground-truthing of identified hot spots may present clear opportunities for mitigation including cutting back overhanging vegetation, and removal of highly flammable vegetation.

5.1 Further Research Though several egress options were highlighted here, much more complexity can be added to the models at every step to determine the optimum egress plan for Sleepy Hollow. The study area was limited to the boundaries of the Sleepy Hollow neighborhood. However, fires are not always easily contained and would likely spread to other neighborhoods in the community. It is recommended that fire models are run with a larger study area in order to capture fire spread characteristics beyond Sleepy Hollow. Optimizing fire model inputs (wind, weather, fuel moisture, and spread conditions) that specifically reflect those of Sleepy Hollow would also produce more accurate fire models. Additionally, igniting fires in several more locations beyond the four cardinal directions can provide a more detailed hot spot analysis. Extending the time frame to past 24-hours might provide further insight into fire behavior, as well as starting the ignition at different times during the day. The hot spot and network analysis could further examine hot spots at different time points so evacuation plans can be optimized in response to immediate and longer term fire spread characteristics. Traffic congestion scenarios and emergency response could also be incorporated into the network analysis to provide a more comprehensive analysis.


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6 References CDFFP. California Department of Forestry and Fire Protection. (2009) Very High Fire Hazard Severity Zones as Recommended by Cal Fire. 5

http://www.mofd.org/_literature_123833/Very_High_Fire_Hazard_Severity_Zone_-_Orinda Chiu, Y. & Liu, H.X.(2008). Emergency Evacuation, Dynamic Transportation Models. Encyclopedia of GIS, pp. 261-267. Church, R. L., and Sexton, R. M. (2002). Modeling small area evacuation: Can existing transportation infrastructure impede public safety?. Caltrans Testbed Center for Interoperability Task Order 3021, Final Rep. Available: http://www.ncgia.ucsb.edu/vital/research/pubs/200204- Evacuation.pdf Cova, T.J., and Church, R.L. (1997). Modelling community evacuation vulnerability using GIS. International Journal of Geographical Information Science, 11(8): 763-784 Cova, T.J., and Johnson, J.P. (2002). Microsimulation of neighborhood evacuations in the urbanwildland interface. Environment and Planning A, 34(12): 2211-2229 Cova, T.J., and Johnson, J.P. (2003). A network flow model for lane-based evacuation routing. Transportation Research Part A: Policy and Practice, 37(7): 579-604 Cova, T.J. (2005) Public safety in the urban-wildland interface: Should fire-prone communities have a maximum occupancy? Natural Hazards Review, 6(3): 99-108 Cova, T.J., Dennison, P.E., Kim, T.H., and Moritz, M.A. (2005) Setting wildfire evacuation trigger-points using fire spread modeling and GIS. Transactions in GIS, 9(4): 603-617 buildings as demand points Dausman, C. (2013) A Great Place to Stay: Orinda's Sleepy Hollow Neighborhood. La Morinda Weekly. Retrieved March 2015. Available: http://www.lamorindaweekly.com/archive/issue0707/ Moraga-Orinda Fire District. Retrieved March 2015. Available: http://www.mofd.org/fireprevention/ do-i-live-in-a-very-high-fire-hazard-severity-zone Rice, C (2013). The Science Behind Eucalyptus Fire Hazards. http://claremontcanyon.org/bibliography/eucalyptus_fire_hazard_carol_rice.pdf


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Tang, T. & M. Wannemacher. (2005). GIS simulation and visualization of community evacuation vulnerability in a connected geographic network model. Middle States Geographer, 38: 22-30. US Census Bureau (2010). 2010 Census Data. http://www.census.gov/2010census/data/. Accessed 4/20/15 U.S. Forest Service (2008). Farsite Version 4.1.055. Wolshon, B., Marchive III, E. (2007). Emergency Planning in the Urban-Wildland Interface:Subdivision-Level Analysis of Wildfire Evacuations. J of Urban Plann Dev, 133: 73-81

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