Appendix B
Communities
Purpose
The purpose of this appendix is to examine, in greater detail, the communities in the
study area. Of the sixteen communities in Four Mile Fire Protection District, two were
found to represent an extreme hazard; four were rated as very high hazard, seven as high
hazard and three as moderate hazard (see Figure1). For easy reference, the map of
communities presented in the main text has been reproduced here as Figure 2. Figure 3
displays this grouping graphically. Table 1 has been included for quick identification.
Community Groupings by Hazard Class
13%
19% Extreme
Very High
25%
High
Moderate
43%
Figure 1
Figure 2
2
Hazard Ratings by Community Extreme
Very High
High
High
0 Moderate
5 1 2
3 4 5
10 6
7 8 9
15 10 11
Rating
12 13
20 14 15
25
16
30
Low Neighborhood
Figure 3
Table 1: Communities by Hazard Rating
1. Rim Road Area 9. Lower 4 mile Canyon
2. Logan Mill 10. Melvina Hill
3. Wallstreet 11. Canon Park
4. Summerville 12. Salina
5. Emmerson Gulch 13. Canyonside
6. Arroyo Chico 14. Red Lion Area
7. Sunset 15. Crisman
8. Camino Bosque 16. Poorman
Extreme Very High High Moderate
3
General Recommendations
A combination of access, ignition resistant construction, and fuels reduction should create
an environment safe for emergency service personnel and provide reasonable protection
to structures from a wildfire. These techniques should also significantly reduce the
chances of a structure fire becoming an ignition source to the surrounding wildlands.
In addition to the suggested mitigations listed for the individual communities, several
general measures can be taken to improve fire safety. The following recommendations
should be noted and practiced by all who live in the Wildland-Urban Interface:
1. Be aware of the current fire danger in the area.
2. Clean your roof and gutters at least 2 times a year, especially during fall
clean up.
3. Stack firewood uphill or on a side contour, at least 30 feet away from
structures.
4. Don't store combustibles or firewood under decks.
5. Maintain and clean spark arresters on chimneys.
6. When possible, maintain an irrigated greenbelt around the home.
7. Connect (and have available) a minimum of 50 feet of garden hose.
8. Post reflective lot and/or house numbers so that they are clearly visible
from the main road. There should also be reflective numbers on the
structure itself.
9. Trees along driveways should be limbed and thinned as necessary to
maintain a minimum 13’6” vertical clearance for emergency vehicle
access.
10. Continually maintain your defensible space:
• Mow grass and weeds to a low height.
• Remove any branches overhanging the roof or chimney.
• Remove all trash, debris and cuttings from the defensible space.
Note
All communities that rated as extreme to high hazard level were recommended for a
parcel level analysis. In the moderate level communities a parcel level analysis was
recommended only if the evaluator found that a significant number of homes had no or
ineffective defensible space, or a significant number of hazards near homes was detected.
In short the recommendation was made if the evaluator felt a parcel level analysis would
generate a noticeable improvement in the community’s defensibility.
4
Technical Terms
The following definitions apply to terms used in the "description” and "comments and
mitigation” sections of this appendix.
Defensible Space: An area around a structure where fuels and vegetation are modified,
cleared or reduced to slow the spread of wildfire toward or from the structure. The design
and distance of the defensible space is based on fuels, topography, and the design of and
materials used in the construction of the structure.
Extended Defensible Space (also known as Zone 3): A defensible space area where
treatment is continued beyond the minimum boundary. This zone focuses on forest
management with fuels reduction being a secondary function.
Shelter-in-Place Areas: There are several ways of protecting the public from an
advancing wildfire. One of these methods is evacuation and involves relocation of the
threatened population to a safer area. Another is to instruct people to remain inside their
homes or public buildings until the danger passes. This concept is new to wildfire in the
United States, but not to hazardous materials incident response where time, hazards, and
sheer logistics often make evacuation impossible. This concept is the dominant modality
for public protection from wildfires in Australia where fast moving, non-persistent fires
in light fuels make evacuation impractical. The success of this tactic depends on a
detailed preplan that takes into account the construction type and materials of the
building used, topography, depth and type of the fuel profile, as well as current and
expected weather and fire behavior. For a more complete discussion of the application
and limitations of Shelter-in-Place concepts see the "Evacuation Routes and Safety Zones
FMU" section in the main report.
Citizen Safety Zone: An area that can be used for protection by residents in the event
that the main evacuation route is compromised. The area should be maintained, cleared of
fuels and large enough for all residents of the area to survive an advancing wildfire
without special equipment or training.
Fuel Break: A natural or constructed discontinuity in a fuel profile utilized to segregate,
stop, or reduce the spread of fire. As a practical matter fuel breaks in the WUI are most
effective against crown fires.
5
Community Assessment Methodology
The community level methodology for this assessment uses a Wildfire Hazard Rating
(WHR), (White/CSFS, 1986) that was developed specifically to evaluate communities
within the Urban Wildland Interface (UWI) for their relative wildfire hazard. The WHR
model combines physical infrastructure such as structure density and roads and fire
behavior components like fuels and topography, with the field experience and knowledge
of wildland fire experts. It has been proven and refined by use in rating over 1,400
neighborhoods throughout the United States.
Numerous fire management professionals were queried regarding their knowledge about,
and experience with, specific environmental and infrastructure factors, and wildfire
behavior and hazards. Weightings within the model were established through these
queries. The model was designed to be applicable throughout the western US.
The model was developed from the perspective of performing a triage on a threatened
community in the path of an advancing wildfire with moderate fire behavior. The WHR
survey and fuel model ground truthing are accomplished by field surveyors with UWI
fire experience. The rating system assigns up to a maximum of 50 points based on six
categories: average lot size, slope, primary aspect, average fuel type, fuel continuity and
surface fuel loading. The higher the community scores, the lower its wildfire hazard. For
example, a community with an average lot size of less than 1 acre and slopes of greater
than 30% would receive 0 points for those factors whereas a community with an average
lot size of 5 acres and slopes of less than 15% would receive 16 points for the same
factors. Additional hazards are then subtracted from the subtotal of points earned in the
six categories to give a final numeric value. The final value is then used to group
communities into one of five hazard ratings: Extreme, Very High, High, Moderate, or
Low.
It is important to note that not all groupings occur in every geographic region. There are
some areas with no low hazard communities, just as there are some areas with no extreme
communities. The rankings are also related to what is customary for the area. That is to
say a high hazard area on the plains of Kansas may not look like a high hazard area on
the western slope of Colorado. The system creates a relative ranking of community
hazard rating in relation to the other communities in the study area. It is designed to be
used by experienced wildland firefighters who have a familiarity with structural triage
operations and fire behavior in the interface.
6
Communities
1. Rim Road
Figure 4
Hazard Rating: Extreme
Does the neighborhood have dual access roads? No
Are there road grades > 8%? Yes
Are all access roads of adequate width? No
Average lot size: >5 Acres
Fuel models found in the neighborhood: 9
Water supply: None
Hazards: Steep slopes, inadequate access roads.
Description:
This neighborhood has steep, rocky, narrow roads with no turnarounds. Access and
egress would be difficult in fire conditions. Address and street signage both need
improvement. Homes are built on steep slopes and at the top of the ridge. Most of the
access is along the ridge. There is a continuous heavy fuel load, with plentiful ladder
fuels. Low power lines and construction equipment parked in the roadway are additional
hazards. The closest water supply for suppression is a cistern on Dixon Gold Trail below
this neighborhood. Some yards are in need of clean up.
Comments & Mitigation Notes:
Reduce ladder fuels. Clean up dead and down material in yards. Remove combustibles
and trash from around homes. Improve roads, signage, and turnarounds. Improvement in
the water supply is critical (see Water Supply FMZ). Most homes need defensible space.
Extended defensible spaces and adequate shelter-in-place areas or safety zones are highly
recommended. A parcel level analysis of this neighborhood is recommended.
7
2. Logan Mill
Figure 5
Hazard Rating: Extreme
Does the neighborhood have dual access roads? No
Are there road grades > 8%? Yes
Are all access roads of adequate width? No
Average lot size: 1-5 Acres
Fuel models found in the neighborhood: 2, 9
Water supply: Draft water at Station 1 and a 12,000
gal. cistern at upper Wendelyn Road.
Hazards: Ravines, inadequate access roads, steep
draws and steep slopes.
Description:
This area has steep roads. Access to many homes is steep and narrow with difficult or
absent turnarounds. There are missing or inadequate street signs and addressing. Many
homes are built at the top or mid-slope on slopes of greater than 30%. There is a heavy
fuel load and a continuous canopy with plentiful ladder fuels. There are many parcels
with tree limbs touching the structures. There is a high structure density in this
community.
Comments & Mitigation Notes:
Thin conifers, especially "dog hair” stands of Douglas fir, and reduce ladder fuels. Clean
up dead and down material. Add reflective street and address signage. Thin trees along
roadways. Improve roads and turnarounds, especially on dead end roads. If it is not
possible to create additional escape routes consider developing shelter-in-place areas or
safety zones. Most homes in this area need defensible space. A parcel level analysis of
this neighborhood is recommended.
8
3. Wall Street
Figure 6
Hazard Rating: Very High
Does the neighborhood have dual access roads? Yes
Are there road grades > 8%? Yes
Are all access roads of adequate width? No
Average lot size: <1 Acres
Fuel models found in the neighborhood: 2, 9
Water supply: Wall Street station and ponds.
Hazards: Steep slopes, inadequate roads, yards
full of flammable materials.
Description:
Wall Street is located at the bottom of Four Mile Canyon along both sides of the creek.
Both sides of the canyon have a high fuel load. Most of the yards are cluttered with trash,
woodpiles and other hazards. Many homes have fuels under and around propane tanks
and trees right up to the buildings. Four Mile Canyon Road has adequate width and
turnarounds, but some of the secondary roads and driveways are steep and have
inadequate turnarounds. The area can be escaped to the west by using the Switzerland
Trail, but egress would be slow.
Comments & Mitigation Notes:
Yards need to be cleaned up, fuels thinned and trees limbed. Many homes need
defensible space. Exposed areas of the structure and propane tanks need to be cleared of
flammable vegetation. Improved access for homes not located on Four Mile Canyon
Road is strongly recommended. As with all structures located in the canyon bottoms,
ignition resistant roofs are highly recommended to prevent ignitions from spotting and
ember cast. Reflective addressing needs to be added on most homes and on private
drives. A parcel level assessment is recommended for this community.
9
4. Summerville
Figure 7
Hazard Rating: Very High
Does the neighborhood have dual access roads? Yes
Are there road grades > 8%? Yes
Are all access roads of adequate width? No
Average lot size: <1 Acre
Fuel models found in the neighborhood: 9
Water supply: Summerville cistern
Hazards: Poor access to the upper area, steep
slopes.
Description:
The main portion of Summerville is a collection of very old houses located along the
road. Access to these is good, however they are at the bottom of steep slopes with heavy
fuel load. Vegetation and combustible materials exist right up to structures. There are
propane tanks surrounded by flammable vegetation. There is a secondary area located up
a steep narrow road with single access. There are three large homes here that are under
construction, and located on steep slopes.
Comments & Mitigation Notes:
Many homes need defensible space. Extended defensible spaces should be considered to
protect older structures from spotting and rolling materials. Combustibles and grasses
should be cleared away from structures and propane tanks. Fuel breaks and thinning
downhill of homes in upper Summerville should be considered. A parcel level analysis of
this neighborhood is recommended.
10
5. Emerson Gulch
Figure 8
Hazard Rating: Very High
Does the neighborhood have dual access roads? No
Are there road grades > 8%? Yes
Are all access roads of adequate width? No
Average lot size: 1-5 Acres
Fuel models found in the neighborhood: 2, 9
Water supply: 5,000 gal. cistern in Emerson Gulch.
Additional water at Wall Street station.
Hazards: Steep draws. Inadequate roads and
turnarounds.
Description:
This lower portion of Emerson Gulch has homes located on slopes as steep as 45%.
Although the fuels are primarily fuel model 2 in the middle and upper areas, there is an
appreciable amount of fuel model 9 with moderate to heavy slash components lower
down. There is only one way in and out, so the fuels hazard in the lower area is
dangerous to the entire community. Most homes need defensible space and better
addressing.
Comments & Mitigation Notes:
Fuels reduction and slash removal should be done downhill of homes and along the road,
especially in the lower area. Most homes need defensible space and yard cleanup. Since
there is no escape from the upper gulch, the development of shelter-in-place areas and/or
safety zones is strongly recommended. A parcel level analysis is recommended.
11
6. Arroyo Chico
Figure 9
Hazard Rating: Very High
Does the neighborhood have dual access roads? No
Are there road grades > 8%? Yes
Are all access roads of adequate width? No
Average lot size: >5 Acres
Fuel models found in the neighborhood: 2
Water supply: Cistern near 411Camino Bosque
Hazards: Steep slopes, inadequate roads
Description:
Fuel loads are mostly moderate, however high mortality makes these fuels more
hazardous than normal. Although most roads are of adequate width, some driveways and
private roads are inadequate. Some homes have combustible materials near structures and
propane tanks. Many homes need defensible space.
Comments & Mitigation Notes:
Eliminate standing dead, and thin dog hair stands. A shaded fuel break to the east of
homes above the steeper drainages should be considered. Clear grasses and combustible
materials away from structures and propane tanks. Extended defensible space, shelter-in-
place areas or safety zones, and yard clean up for most homes is recommended. A parcel
level analysis is recommended.
12
7. Sunset
Figure 10
Hazard Rating: High
Does the neighborhood have dual access roads? Yes
Are there road grades > 8%? Yes
Are all access roads of adequate width? Yes
Average lot size: <1 Acre
Fuel models found in the neighborhood: 2,9,10
Water supply: 50,000-60,000 gal. pond at 10571 Four
Mile Canyon Road.
Hazards: Steep slopes, dilapidated mining shacks,
heavy insect kill.
Description:
Sunset is primarily located in a wide section of Four Mile Canyon with good access and
4WD escape routes to both the south and north. Some homes are located up steep
driveways and private roads. Homes located in Pennsylvania Gulch have steep, rocky
single access. There are a lot of snags from insect activity. There is an area of heavy blow
down on the north slope. Most homes need defensible space. Tree limbs touch most
homes and tall grasses grow up to foundations.
Comments & Mitigation Notes:
The pond would be a good place to add a dry hydrant. Homes need defensible space and
yard clean up. Remove dead and diseased vegetation. Investigate the possibility of
combining private and public landowners to thin stands and remove snags on slopes
above homes. Extended defensible space especially for homes on north slopes is
recommended. A parcel level analysis is recommended.
13
8. Camino Bosque
Figure 11
Hazard Rating: High
Does the neighborhood have dual access roads? No
Are there road grades > 8%? Yes
Are all access roads of adequate width? No
Average lot size: 1-5 Acres
Fuel models found in the neighborhood: 2
Water supply: 10,000 gal. cistern near 411 Camino
Bosque
Hazards: Houses on ridge tops, steep slopes,
narrow steep access to some homes and
poor turnarounds in some areas.
Description:
This area has had some mitigation. Limbing and thinning near homes is apparent,
however tall grasses need to be mowed away from houses and propane tanks. There are
many homes located mid-slope on slopes of up to 34% and at the top of ridges. The entire
area needs better address signage. Main access roads are steep but good, but some homes,
particularly in the lower section, have steep, rocky, narrow access with poor turnarounds.
Some homes need defensible space.
Comments & Mitigation Notes:
Improve poor roads in the lower section. Extended defensible space, shelter-in-place
areas and/or safety zones are recommended. Improve address and road signage. A parcel
level analysis is recommended.
14
9. Lower Four Mile Canyon
Figure 12
Hazard Rating: High
Does the neighborhood have dual access roads? Yes
Are there road grades > 8%? Yes
Are all access roads of adequate width? Yes
Average lot size: 1-5 Acres
Fuel models found in the neighborhood: 2
Water supply: 20,000 gal. Cistern above 357
Canyonside. Dry hydrant in the area
may be usable. Possible draft water (see
description).
Hazards: Untested bridges. Steep slopes.
Description:
Homes closer to Boulder Canyon are generally built in the riparian corridor along the
creek. Although the heavy vegetation near these homes is mostly riparian, there is a threat
of spotting and rolling materials from the steep slopes, many over 50%, of primarily fuel
model 2 above structures. Access to many structures requires crossing bridges that are
neither tested nor marked. Some homes farther up canyon have been built mid-slope and
although access is steep to some of these, it is generally adequate. There is a dry hydrant
at Boulder Mountain Lodge and draft access is available, but the creek often has little or
no water in the lower canyon in late summer and fall.
Comments & Mitigation Notes:
Most homes need defensible space. As with all structures located in the canyon bottoms
ignition resistant roofs are highly recommended to prevent ignitions from spotting and
ember cast. Address signage needs improvement. Bridges should be marked where their
condition is known (see main report). A parcel level analysis is recommended.
15
10. Melvina Hill
Figure 13
Hazard Rating: High
Does the neighborhood have dual access roads? No
Are there road grades > 8%? Yes
Are all access roads of adequate width? Yes
Average lot size: 1-5 Acres
Fuel models found in the neighborhood: 2
Water supply: 10,000 gal. cistern at the fork in Melvina
Hill Road. Additional water is available
at Wall Street.
Hazards: Steep draws and roads. Many snags.
Description:
This neighborhood has steep but good roads. A lot of mitigation has been done around
homes and roads, but slash removal needs to be completed especially around roads. This
is another area with many snags from insect kill. Although the dominant vegetation is
Ponderosa pine, there are more Junipers here than in other areas. There are few homes on
the steeper, and more hazardous, east side, but it looks as though the area is being
surveyed for development. If this is the case it may make this community of higher
concern.
Comments & Mitigation Notes:
Continue to limb and thin near homes. Continue removal of dead and diseased trees.
Mow grasses away from structures. Develop shelter-in-place areas and/or safety zones. A
shaded fuel break between homes on the west side and the steep drainage to the west is
recommended. Some homes need defensible spaces. A parcel level analysis is
recommended.
16
11. Cañon Park Area
Figure 14
Hazard Rating: High
Does the neighborhood have dual access roads? No
Are there road grades > 8%? Yes
Are all access roads of adequate width? No
Average lot size: <1 Acre
Fuel models found in the neighborhood: 2
Water supply: City of Boulder hydrant at 101 Pearl and
draft water available from Boulder
Creek.
Hazards: Steep slopes, narrow dead end roads, no
turnarounds, shake roofs, power lines.
Description:
The area can be divided into three parts. Cañon Park Drive is composed of older homes
located on the north side of Boulder Creek. Access is flat, but narrow and lacking
adequate turnarounds. These homes are mainly threatened by spotting and rolling
materials from the south-facing slope above them. The area on the south side of Boulder
Canyon has three wood structures with shake roofs. Access is better here, but ember cast
would easily involve structures. There are some homes on the north side of Boulder
Canyon east of Cañon Park Drive. Three of these are cantilevered wood structures
located mid-slope up a narrow, dead end driveway. These structures would be very
hazardous to defend.
Comments & Mitigation Notes:
The structures on Cañon Park Drive need defensible spaces particularly on the north side
where there is the most risk from spotting and rolling materials. The homes to the east
need yard cleanup and wider access with a turnaround. Consider installing non-
combustible materials under the cantilevered portions. Grasses and flammable vegetation
should be cleared away from all structures. Reflective address signage should be added to
all homes, and any improvements in road widths and turnarounds that are possible should
be considered. A parcel level analysis is recommended.
17
12. Salina
Figure 15
Hazard Rating: High
Does the neighborhood have dual access roads? Yes
Are there road grades > 8%? Yes
Are all access roads of adequate width? Yes
Average lot size: <1 Acre
Fuel models found in the neighborhood: 8, 9
Water supply: 10,000 gal. cistern at Salina station.
Hazards: Homes with no vehicle access,
combustibles stored near homes, low
power lines, steep slopes.
Description:
This is another community surrounded by steep slopes (up to 60%). There are parcels
with flammable debris near structures. There are low power lines in the community and
some homes are only accessible by steep narrow staircases. Most homes need defensible
spaces.
Comments & Mitigation Notes:
Clean up around structures. Remove or limb trees touching structures. Improve address
signage. Most homes in this area need defensible space. A parcel level analysis of this
neighborhood is recommended.
18
13. Canyonside
Figure 16
Hazard Rating: High
Does the neighborhood have dual access roads? No
Are there road grades > 8%? Yes
Are all access roads of adequate width? No
Average lot size: 1-5 Acres
Fuel models found in the neighborhood: 2
Water supply: 20,000 gal. cistern above 357
Canyonside.
Hazards: Steep slopes and roads.
Description:
A lot of mitigation work has been done in this community. There is noticeably less insect
kill in this area. Roads are generally adequate except for a few narrow driveways. The
main problem here is that most homes are located mid-slope on steep (over 40%) slopes,
and there is only one way in and out of the community.
Comments & Mitigation Notes:
Improve narrow driveways if possible. Consider extended defensible spaces, shelter-in-
place areas and/or safety zones. Consider a shaded fuel break below homes or encourage
homeowners to thin vegetation on slopes below homes. A parcel level analysis is
recommended.
19
14. Red Lion Area
Figure 17
Hazard Rating: Moderate
Does the neighborhood have dual access roads? No
Are there road grades > 8%? Yes
Are all access roads of adequate width? Yes
Average lot size: >5 Acres
Fuel models found in the neighborhood: 2, 9
Water supply: Fill site at the pull out West of the Red
Lion, and draft water from Boulder
Creek.
Hazards: Steep slopes, ravines
Description:
The area on the north side of Boulder Canyon has slopes up to 45% with moderate loads
of primarily fuel model 2. Roads are steep, but otherwise good. There are some parcels
with tree limbs touching structures. Woodpiles and other combustibles are stored against
structures. The area on the south side of Boulder Canyon has the Red Lion Restaurant
which is on city water. There are several cabins clustered around the restaurant. These are
all near the creek and have irrigated greenbelt. There are a few homes located up a steep
drainage to the south. That area has a high loading of fuel model 9. There is a 4WD road
that provides an escape to Flagstaff Mountain, but a landowner usually blocks the access.
This route, Chapman Road, is also steep and poorly maintained.
Comments & Mitigation Notes:
Cut trees away from homes and thin downhill of homes. Some homes in this area need
defensible space.
20
15. Crisman
Figure 18
Hazard Rating: Moderate
Does the neighborhood have dual access roads? No
Are there road grades > 8%? No
Are all access roads of adequate width? No
Average lot size: <1 Acre
Fuel models found in the neighborhood: 2
Water supply: Draft water from Four Mile Creek (low
flow and not always reliable)
Hazards: Low power lines.
Description:
This area has moderate loads of primarily fuel model 2. The community is at the bottom
of slopes up to 45%. Access roads are flat, but lack turnarounds, and there is an unrated
bridge that must be crossed to access several homes. Some parcels have a lot of
vegetation against structures.
Comments & Mitigation Notes:
This would be a good place to consider a dry hydrant or a cistern. Low power lines
should be marked or relocated. Some houses need defensible spaces, and all need better
address signage. Improve turnarounds.
21
16. Poorman
Figure 19
Hazard Rating: Moderate
Does the neighborhood have dual access roads? Yes
Are there road grades > 8%? Yes
Are all access roads of adequate width? Yes
Average lot size: >5 Acres
Fuel models found in the neighborhood: 1, 2, 8
Water supply: 10,000 gal. cistern on Poorman Road.
Draft pond and pump station at Four
Mile Canyon Road and Poorman Road.
Hazards: Steep slopes on the Sunshine Canyon
side.
Description:
This neighborhood has light to moderate loads of fuel models 1, 2 and 8. Slopes up top
are generally less than 20%. The lower area is steeper (up to 30% slope) and has a higher
fuel load. There are few homes here and the access is good. This community continues
outside the Four Mile FPD, where its hazard level increases due to steep slopes, more
fuels and greater structure density on the Sunshine Canyon side.
Comments & Mitigation Notes:
Some homes may need defensible space. Consider a fuel break if possible to separate
homes from the steep slopes on the Sunshine Canon side. This community would rate as
high or very high if the analysis were continued into the Sunshine FPD.
22