Waldo Canyon Fire
2014 BAER Effectiveness Monitoring
Rocky Mountain Field Institute
February 18, 2015
Rocky Mountain Field Institute
th
815 South 25 Street, Suite 101
Colorado Springs, CO 80904
Dedicated to the conservation and stewardship of public lands
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TABLE OF CONTENTS
1. Summary ....................................................................................................................................... 3
2. Background ................................................................................................................................... 4
3. Data Collection Protocols .............................................................................................................. 6
4. Fountain Creek Watershed ........................................................................................................... 9
5. Camp Creek Watershed ............................................................................................................... 11
6. Results and Discussion ................................................................................................................. 12
a.
b.
c.
d.
Upper Williams Canyon ................................................................................................... 12
Lower Williams Canyon ................................................................................................... 21
Wellington Gulch .............................................................................................................. 28
Camp Creek ..................................................................................................................... 32
7. Compilation of Monitoring and Research Activities in the Waldo Canyon Burn Scar ................... 35
8. References .................................................................................................................................... 44
9. Acknowledgements ....................................................................................................................... 44
10. Appendix A.................................................................................................................................... 45
11. Appendix B.................................................................................................................................... 48
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SUMMARY
Recently burned watersheds frequently produce increased erosion and debris flows in response to
moderate to severe storm events. The construction and installation of below-grade sediment detention
basins in ephemeral drainages can help mitigate impacts from flooding by capturing sediment and
reducing the velocity of water flows. The basins prevent gullies from forming and keep the water table
high in the alluvial valleys increasing the success of bank stabilizing, riparian vegetation recovery. The
establishment and spread of non-native species following wildfires can pose threats to long-term native
plant recovery. Post-fire native seeding can help stabilize soils, reduce erosion, and combat non-native
species invasions. In response to the Waldo Canyon Fire, USFS BAER funds were used to construct
several sediment detention basins in priority sub-watersheds within the burn scar. Reseeding efforts and
hand crew stabilization work were also implemented to stabilize hillslopes and trap sediment adjacent to
the sediment detention basins. The effectiveness of the basins in capturing sediment and minimizing
downstream erosion as well as the status of revegetation efforts were monitored during the summer of
2014 through longitudinal profile surveys, cross-section surveys, and photopoints.
The longitudinal profile surveys conducted at the Upper Williams Canyon and Wellington Gulch sites
where sediment detention basins were installed revealed minimal changes in channel gradient and a
relatively stable channel bed for the duration of the monitoring period (see Appendix B – Monitoring
Locations in Williams Canyon, Wellington Gulch, and Camp Creek Sub-Watershed). In both locations, the
sediment detention basins were functioning properly to capture sediment and reduce flow velocity. As the
basins filled throughout the monitoring period, an overall pattern of aggradation was observed below the
basins where the flood flows were dispersed across the floodplain. Minimal scour and bank erosion were
observed downstream of the basins. The longitudinal profile surveys at the Lower Williams Canyon site
were conducted where a stable alluvial fan was re-established in a side channel and the mainstem of
Williams Creek was stabilized with cross vanes. This reach revealed more pronounced changes in the
channel gradient and channel bed. The stable stream channel in this section is an intermittent “B”
channel. A consistent pattern of channel adjustment was observed along the entire reach.
The cross-section surveys conducted at the Upper Williams Canyon and Wellington Gulch sites revealed
minimal changes to stream morphology or geometry. Bank location and channel width at each monitoring
location remained relatively stable throughout the monitoring period. Cross-section surveys conducted at
the Lower Williams Canyon site revealed relatively stable channel morphology and geometry, but more
definitive locations of active bank erosion and degradation were observed. The deposition of large bed
material was observed where the tributary joined Williams Creek on the reconstructed fan. The
reconstructed fan was stabilized with log sills every 15 feet to ensure aggradation of sediment during
flooding. A marked change in bed material composition and size was observed from cross-section #1 to
cross-section #3 indicating higher flow velocities and energy from the side channel.
Repeated photographs taken within the Camp Creek drainage suggest restoration efforts of the basin
access road were successful. Native vegetation was reestablishing itself on the hillslopes and snags
installed perpendicular to the slope were holding in place, helping stabilize the soil surface and slow down
water flows. The sediment detention basin was functioning properly to capture sediment originating from
upstream reaches. The outlet sill of the sediment detention basin was also performing well with minimal
evidence of erosion downstream of the basin. Log-erosion barriers installed along the right bank of the
basin were functioning to slow down water flows and minimize further rill erosion. Native vegetation
seeded behind the log-erosion barriers was establishing itself and helping to stabilize the soil surface.
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It is recommended that future monitoring of each of the sites continue in 2015 to better assess the
effectiveness of the sediment detention basins, riparian vegetation recovery, as well as the success of
reseeding and hillslope stabilization efforts. Natural streams and drainages are dynamic systems that are
in a constant state of change. Longitudinal profile and cross-section surveys will differ from year to year
based on changes in the watershed. However, continued evidence of deposition as well as changes in
stability will help determine long-term success of post-fire BAER restoration treatments implemented in
the Waldo Canyon burn scar.
Storm Events
Cross-section and longitudinal surveys were conducted within 5 days after storm events in July, August,
and October, 2014. On July 15, approximately 0.50 inches of rain fell on the Waldo Canyon burn scar,
approximately 0.75 inches fell on July 16, and approximately 1.30 inches fell on July 19. A July 29 storm
delivered approximately 0.64 inches of rain to the area, 0.80 inches on July 30, and 0.11 inches on July
31. Finally, an October 10 storm delivered approximately 0.13 inches of rain to the burn scar.
BACKGROUND
The Waldo Canyon Fire burned 18,247 acres on the Pike National Forest between June 23 and July 10,
2012. The fire affected 4 major watersheds in and around Colorado Springs: Fountain Creek, Camp
Creek, Douglas Creek, and Monument Creek (Figure 1). Approximately 41% of the area burned (7,586
acres) was classified as low severity burn, 40% (7,286 acres) was classified as moderate severity, and
19% (3,375 acres) was classified as high severity burn. Of
the lands burned, approximately 14,422 acres (79%) were
located within the National Forest System, 3,678 acres
(20%) were on private lands, and 147 acres (<1%) were
on Department of Defense lands.
Immediately after the fire, an interagency Burned Area
Emergency Response (BAER) team examined the effects
of the fire and risk to life and property. The BAER team
coordinated emergency stabilization treatments with the
Natural Resources Conservation Service (NRCS),
Colorado Department of Transportation, El Paso County,
U.S. Geological Survey (USGS), National Weather Service
(NWS), City of Manitou Springs, and the City of Colorado
Springs along with other agencies responsible for flood
control and assistance to landowners. In 2012, immediate
BAER treatments included helicopter application of mulch,
installation of flash flood warning signs and closures,
removal of hazard trees, storm-proofing roads, and
noxious weed treatments. Other BAER mitigation and
restoration efforts include: trail stabilization, stream
channel re-shaping, hand treatments to prevent head cuts,
installation of straw wattles, installation of log erosion
Figure 1. Major watershed delineation of Camp Creek,
Douglas Creek, Fountain Creek, and West Monument
Creek (Rosgen et al., 2013).
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barriers, improving culvert run outs, stabilizing gullies below culverts, replacing culverts, and construction
of below-grade detention basins in priority sub-watersheds (Table 1).
Table 1. Summary of flood mitigation treatments in the Waldo Canyon burn scar as of May 30, 2014.
Work
U.S. Forest Service
Private Lands
Total to Date
Detention Basins Constructed
38
18
56
Feet of Stream Channel Reshaped
31,060
12,300
43,360
Miles of USFS Roads Maintained
21.0
1.06
22.06
Acres of Hand Treatments
>1,000
>500
>1,500
Linear Feet of Debris Deflectors
1,928
570
2,498
Linear Feet of Log Erosion Barriers
6,916
10,632
17,548
Culvert Installments
15
-
15
Acres of Straw Mulch
1,045
-
1,045
Acres of Wood Mulch
2,000
-
2,000
In April 2013, a post-fire Watershed Assessment for River Stability and Sediment Supply (WARSSS)
study was completed to quantify post-fire streamflow and sediment yields related to burn intensity,
location, extent, and consequence of hillslope as well as hydrologic and channel processes; 24,248 acres
encompassing 89 sub-watersheds were analyzed. Results from the WARSSS study culminated in
development of the “The Waldo Canyon Fire Master Plan for Watershed Restoration and Sediment
Reduction” (Rosgen et al., 2013), which prioritized restoration activities within the Waldo Canyon burn
scar (Table 2).
A total of 38 sediment detention basins have been constructed within the Waldo Canyon burn scar on
Forest Service managed lands. Sediment detention basins are below grade structures that function as
“borrow” pits for material used to fill active gullies, re-connect the floodplain, and prevent the water table
from lowering. Sediment detention basins capture eroded soil and debris that is displaced during storm
events. These structures are designed to fill with sediment slow flood-flows, and once full, recreate
floodplains that naturally spread water over a larger area and dispersing sediment. Restoring gullies helps
to reduce downcutting, prevent head cuts and spread floodwater flows across the floodplain. Restoration
will reduce bank erosion and improve water quality.
Basins are constructed in ephemeral drainages where a wide floodplain and/or a braided “D” channel are
the stable stream type. Basins may be up to 100 feet in length and span the entire valley bottom. Basins
consist of a log crib wall, the catchment area, and outlet sills.
In the spring of 2014, the U.S. Forest Service (USFS) partnered with the Rocky Mountain Field Institute
(RMFI) to measure the effectiveness of USFS-led BAER efforts in three sub-watersheds of the Waldo
Canyon burn scar: 1) Williams Canyon (Fountain Creek Watershed), 2) Wellington Gulch (Fountain Creek
Watershed), and 3) Camp Creek (Camp Creek Watershed). The USFS developed the Level II monitoring
protocol, established the monitoring sites, trained RMFI staff and is responsible for data review and
analysis.
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Table 2. Summary of estimated pre-and post-fire sediment yields by process (Rosgen et al., 2013).
Hillslope
Processes
Hydrologic Processes
Watershed
Water Yield
(acre-ft/yr)
Flow-Related
Sediment
(tons/yr)
PrePostFire
Fire
PreFire
PostFire
Camp Creek
2,115
3,702
71
Douglas Creek
1,511
2,156
Fountain Creek
2,500
4,822
West Monument Creek
2,747
Totals
8,873
Surface
Erosion
(tons/yr)
Roads
and
Trails
(tons/yr)
Channel
Processes
Streambank
Erosion
(tons/yr)
Total
Introduced
Sediment
(tons/yr)
6,750
11,694
16,897
4,193
751
47
7,834
4,057
236
6,108
10,401
90
25,075
7,303
619
11,318
19,241
4,035
104
7,489
2,532
429
7,183
10,143
14,715
312
57,295
18,085
2,035
31,359
51,479
Level II monitoring collects information to confirm overall effectiveness of certain regionally important
response actions in meeting BAER objectives, and utilizes more quantitative methodologies designed to
address specific issues. The monitoring plan consisted of the following objectives, which are answered
throughout this report:
Level II Monitoring Objectives
1. Monitoring questions:
a. Did the structures function as designed and help to store and spread sediment across the
floodplain?
b. Was there damage to the structures? If so, are additional treatments necessary?
c. What type of storm events did the structure receive prior to monitoring/during monitoring?
d. Are there indicators of channel downcutting? If so, are more structures needed?
2. Measurable indicators:
a. Sediment deposition
b. Percent change in vegetation cover
3. Data collection and survey techniques consistent with appropriate protocols:
a. Longitudinal-profiles
b. Cross-sections
c. Photopoints
4. Analysis, evaluation, and reporting techniques:
a. Summarize data into graphs
5. Monitoring report timeframes
DATA COLLECTION PROTOCOLS
The field surveys were conducted per the guidelines of the USFS’s “Stream Channel Reference Sites: An
Illustrated Guide to Field Technique” (Harrelson et al., 1994) and “Field Survey Procedures for
Characterization of River Morphology” (Rosgen, 1996). These measurements included collecting data for
longitudinal profile and cross-section profile surveys as well as photopoints. Descriptions of monitoring
protocols for each measurement are provided below.
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Longitudinal Profile Surveys
Longitudinal profile surveys enable evaluation of changes in slopes, streambed features, and channel
aggradation/degradation. The surveys are ideally compared on a yearly basis to note and/or compare
aggradation, degradation, head cuts, and areas of mass wasting.
At each of the three monitoring locations, permanent benchmarks were established at the upstream and
downstream ends of the reach. Each benchmark was georeferenced with GPS coordinates. A measuring
tape was then run from upstream to downstream in the center of the channel so that it intersected with the
center of the uppermost cross-section tape and lowermost cross-section tape. Measurements were taken
every 3 to 4 feet in the middle of the channel. The initial station was recorded as 0+00 and thalweg and
water depth were also recorded. Stationing along the profile tape was recorded in tenths of feet and
elevation was recorded in hundredths of feet. The location of the cross-section along the longitudinal
profile was noted. In addition, photopoints were established at each cross-section intersection as well as
the start/end of the longitudinal profile, and 4 different photos were taken (upstream, downstream, right
bank, left bank). If the entire profile could not be surveyed from the initial location of the level, a turning
point was used whereby the laser was moved, reset, and the same point was surveyed again. At the end
of each survey reach, the top of the last feature and the downstream benchmark were surveyed. Prior to
removing the tape, all data sheets were examined for quality control. Data were entered into Excel and
longitudinal profiles were plotted. Four longitudinal profile surveys were completed in Upper Williams
Canyon (FC-002) and 3 were completed in both Lower Williams Canyon (FC-002) and Wellington Gulch
(FC-010). Baseline measurements were recorded in all sub-watersheds (Table 3). All longitudinal profile
surveys (except baseline survey) were taken within 5 days of a major storm event.
Cross-Section Surveys
Cross-section surveys enable assessment of floodplain connectivity, changes in bed stability, channel
enlargement, and lateral migration. At each of the three monitoring locations (Upper Williams, Lower
Williams, Wellington Gulch), permanent benchmarks were established on either bank at the bankpin.
Each benchmark was georeferenced with GPS coordinates. A tape was stretched from left bank to right
bank facing downstream so that station 0 was directly over the left bank benchmark. The tape was taut
across the reach. The survey rod was placed on top of the left bank benchmark and was held as steady
and vertical as possible while moving the receiver up/down until the audible tone indicated a proper
reading (fast beeps: too high; slow beeps: too low; solid beep: level). Readings were made in hundredths
of feet. The rod was then moved beside the benchmark and the previous steps were repeated to
determine the elevation. Measurements were continued from right to left, surveying breaks in elevation
and prominent features within the reach. Each cross-section survey included top of benchmarks (left and
right), top of bank (left and right), edge of water (left and right), thalweg, and limits of depositional
features. Longitudinal profile intersections were also noted where the cross-section tape crossed the
longitudinal profile tape. In addition, photopoints were established for each cross-section survey and 4
different photos were taken (upstream, downstream, right bank, left bank). If the entire profile could not be
surveyed from the initial location of the level, a turning point was used whereby the laser was moved,
reset, and the same point was surveyed again. Prior to removing the tape, all data sheets were examined
for quality control. Data were entered into Excel and cross-section surveys were plotted. Baseline
measurements were recorded for all cross-section surveys in Upper and Lower Williams Canyon (FC002), but not in Wellington Gulch (FC-010). Four cross-section surveys were completed in Upper Williams
and measured 4 different times, 3 cross-section surveys were completed in Lower Williams and
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measured 4 different times, and 1 cross-section-survey was completed in Wellington Gulch and measured
3 different times (Table 3). All cross-section surveys (except baseline surveys) were completed within 5
days of a major storm event.
Table 3. Frequency of longitudinal and cross-section survey measurements in Upper Williams, Lower Williams, and
Wellington Gulch.
Sub-watershed
Upper Williams Canyon
Lower Williams Canyon
Wellington Gulch
LP
XS#1
XS#2
XS#3
XS#4
06/27/2014 (B)
06/27/2014 (B)
06/27/2014 (B)
06/27/2014 (B)
06/27/2014 (B)
07/21/2014
07/21/2014
07/21/2014
07/21/2014
07/21/2014
08/04/2014
08/04/2014
08/04/2014
08/04/2014
08/04/2014
10/21/2014
10/18/2014
10/18/2014
10/18/2014
10/18/2014
-
07/07/2014 (B)
07/07/2014 (B)
07/07/2014 (B)
-
07/28/2014
07/28/2014
07/28/2014
07/28/2014
-
08/05/2014
08/05/2014
08/05/2014
08/05/2014
-
10/18/2014
10/18/2014
10/18/2014
10/18/2014
-
07/22/2014
07/22/2014
-
-
-
08/06/2014
08/06/2014
-
-
-
10/21/2014
10/21/2014
-
-
-
Note: LP = longitudinal profile; XS = cross-section; B = baseline.
Photopoints
Photopoint monitoring is a standardized procedure, developed largely by Dr. Fred Hall of the USFS for
taking precisely replicable photographs of resources that require long-term management (Hall, 1997).
Photopoint monitoring is both a qualitative and quantitative tool that can assist resource managers in
detecting unacceptable conditions in target resources before severe or irreversible changes occur, and
allow time to implement corrective actions. The technique can also be used to assess the success or
failure of management decisions based on the use of clearly defined indicators and standards. The
photopoint monitoring technique can be used as an early warning system in conjunction with other
quantitative approaches or as an independent monitoring procedure.
At each cross-section survey in Upper Williams, Lower Williams, and Wellington Gulch, photopoints were
established as follows: from left bank looking to right bank; from right bank looking to left bank; from
above the cross-section looking downstream; and from below the cross-section looking upstream.
Additional photopoints were established at other appropriate locations where the channel could be
observed. In addition, photopoints were established for each longitudinal profile survey completed at each
of the three monitoring sites. In the Camp Creek sub-watershed (CC-014), four photopoint locations were
established - sediment detention basin, decommissioned road used to install the basin, outlet sill of the
detention basin, and log-erosion barriers installed adjacent to the basin.
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FOUNTAIN CREEK WATERSHED
The Fountain Creek Watershed (Figure 2) is located
along the central front range of Colorado. The
headwaters of Fountain Creek begin west of the City
of Colorado Springs near Woodland Park. The northcentral portion of the watershed discharges to
Monument Creek, which drains to Fountain Creek
near the downtown area of Colorado Springs.
Fountain Creek ultimately discharges to the
Arkansas River near Pueblo, Colorado. The area is
characterized by extremes in temperature and
precipitation, large elevation changes, steep
gradients, diverse ecosystems, and a multitude of
water uses. Portions of El Paso, Teller, and Pueblo
counties make up the watershed, which
encompasses the municipalities of Pueblo, Colorado
Springs, Fountain, Manitou Springs, Green Mountain
Falls, Woodland Park Palmer Lake, and Monument.
The Fountain Creek Watershed is 7,163 acres
encompassing 18 sub-watersheds. 63% of the
watershed burned during the Waldo Canyon Fire
(29% low intensity, 30% moderate intensity, and 5% Figure 2. Fountain Creek sub-watershed delineation (Rosgen et
al., 2013). Williams Canyon (FC-002) and Wellington Gulch
high intensity). Two sub-watersheds within the
(FC-010) sub-watersheds are outlined in yellow.
Fountain Creek watershed were identified for
monitoring, Williams Canyon (FC-002) and Wellington Gulch (FC-010). In June 2013, three sediment
detention basins were constructed in the lower portion of the Williams Canyon sub-watershed (FC-002) to
help mitigate sediment transport and reduce floodwater flow. Williams Canyon is a 1,234-acre watershed.
Williams Creek is an intermittent creek that also flows subterranean due to karst formations. Williams
Creek is the source water for the Manitou Springs mineral water and is considered a high value stream.
On July 1, 2013 Williams Creek flooded into the town of Manitou Springs with an 1,100 cfs, 6.5 feet max
flood depth storm flow in response to 0.62 inches of rain in about 20 minutes. Stormwater improvement
work in Manitou Springs is ongoing. All three of the basins filled with sediment and debris following the
storm event. Two of the three basins were re-excavated to protect life and property on USFS and
downstream properties. Generally, this re-excavation is not necessary to perform because the purpose of
the sediment detention basin’s design is to re-create the floodplain and disperse flows evenly. However,
due to the availability of equipment on site and the magnitude of downstream values at risk, additional
mitigation work was implemented.
The USFS selected to monitor the uppermost basin (Upper Williams Canyon monitoring site), which
includes the inlet and outlet reaches surrounding the basin. The techniques used for surveying and
monitoring are longitudinal profiles, cross-sections, and photopoints.
Approximately 1 mile south of the Upper Williams Canyon monitoring site is an unnamed tributary that
feeds Williams Creek. The USFS selected to monitor the effectiveness of BAER implementation
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procedures at this tributary (Lower Williams Canyon monitoring site) using longitudinal profiles, crosssections, and photopoints.
In September 2013, seven sediment detention basins were constructed in the upper portion of the
ephemeral Wellington Gulch sub-watershed (FC-010). Wellington Gulch is a 1,104-acre watershed that
funnels into private property and State Highway 24. State Highway 24 is critical to the 50,000 estimated
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daily commuters. The USFS selected the 4 sediment detention basin from the top to conduct monitoring
efforts using longitudinal profiles, cross-sections, and photopoints.
Summary of monitoring activities in Williams Canyon (upper and lower) and Wellington Gulch
1. Williams Canyon (Fountain Creek, sub-watershed FC-002; watershed summary in Appendix A)
a. RMFI Monitoring (map of Williams Canyon monitoring locations included in Appendix B)
i. Upper Williams Canyon
1. Cross-section survey
a. 4 transects measuring the upper-most basin including the basin
profile, inlet, outlets, and outlet sill.
2. Longitudinal profile survey
a. 1 transect measuring the basin profile, inflows, and outflows,
3. Monumented photopoints established to determine sediment deposition and
percent change in vegetative cover.
ii. Lower Williams Canyon
1. Cross-section survey
a. 3 transects measuring the outflow at the confluence of the main
channel of Williams Canyon and the un-named side tributary; This
location marks the downstream extent of heavy equipment work
done by the USFS on the main stem of Williams Canyon. Heavy
equipment did not reshape the side tributary.
2. Longitudinal profile survey
a. 1 transect measuring the transition from the un-named tributary to
the main stem of Williams Canyon.
3. Monumented photopoints established to determine sediment deposition and
percent change in vegetative cover.
2. Wellington Gulch (Fountain Creek, sub-watershed FC-010; watershed summary in Appendix A)
a. RMFI Monitoring (map of Wellington Gulch monitoring locations included in Appendix B)
i. Wellington Gulch
1. Cross-section survey
th
a. 1 transect measuring the 4 basin from the top including the basin
profile, inflows, outflows, and outlet sill.
2. Longitudinal profile survey
a. 1 transect measuring the basin profile, inflows, and outflows,
3. Monumented photopoints established to determine sediment deposition and
percent change in vegetative cover.
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CAMP CREEK WATERSHED
The Camp Creek Watershed is approximately 11.2
square miles (7,168 acres) in size (Figure 3). Camp
Creek is within the larger Upper Fountain Creek HUC10 – Fifth Level sub-watershed – 1102000302.
Camp Creek is a tributary to Fountain Creek and
flows through Queens Canyon, then becomes
unconfined near the Glen Eyrie Conference Center
on the westside of Colorado Springs. The Camp
Creek drainage corridor extends through Garden of
the Gods Park and Rock Ledge Ranch Historic Site,
then down the median of 31st Street through the
Pleasant Valley neighborhood to a confluence with
Fountain Creek near U.S. Highway 24. The upper
portion of the watershed is USFS managed lands,
the middle (Queens Canyon) is private property, and
the lower watershed is owned by the City of
Colorado Springs.
Of the total area analyzed in the BAER study
(24,248 acres), 5,526 acres encompassing 36
micro-watersheds were included in the Camp Creek
Watershed. Of the total watershed area, 78% burned Figure 3. Camp Creek sub-watershed delineation (Rosgen et
al., 2013). The Camp Creek sub-watershed (CC-014) is
(36% low intensity, 37% moderate intensity, and 5% outlined in blue.
high intensity).
In September 2013, five sediment detention basins were constructed in the Camp Creek Watershed to
help mitigate sediment transport and disperse floodwater energy. The USFS selected 4 locations within
sub-watershed CC-014 to establish monumented photopoints to monitor changes in the surrounding
landscape and vegetation. A summary of monitoring activities conducted in Camp Creek is included
below.
Summary of monitoring activities in Camp Creek
1. Camp Creek (Camp Creek, sub-watershed CC-014; watershed summary in Appendix A)
a. RMFI Monitoring (map of Camp Creek monitoring locations included in Appendix B)
i. Camp Creek
1. Monumented photopoints established in 4 locations (sediment detention
basin, decommissioned road used to construct basin, outlet sill of basin, logerosion barriers installed adjacent to basin) to determine general changes in
landscape and vegetation recovery.
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RESULTS AND DISCUSSION
Upper Williams
Longitudinal Profile
The longitudinal profile survey at the Upper Williams reach was approximately 445 feet (135.7 meters) in length (Figure 4). The average overall
slope of the reach was 9.19%. This profile started in the intermittent drainage above an empty sediment detention basin and was carried through
the basin and downstream of the basin. Where the basin had ponded water that was too deep and above the rod, measurements were not taken.
Comparison of the three post-storm event longitudinal profiles revealed a general pattern of aggradation along the entire reach, but especially
between stations 260 and 330 (the sediment detention basin). As the basin began to fill with sediment, additional aggradation can be observed
below the sediment detention basin (station 330 to 445), particularly for the last survey completed on October 10, 2014. Channel forming
processes and adjustments are observed below the sediment detention basin as a new, intermittent steam channel is established. These are
areas that will be monitored in 2015 to determine trends. Photographs taken at the start (Figure 5) and end (Figure 6) of the longitudinal profile
visually support the general pattern of aggradation observed along the reach throughout the duration of the monitoring period.
Upper Williams: Longitudinal Profile 2014
06/27/2014
100
07/21/2014
96
08/04/2014
92
10/21/2014
Elevation (ft)
88
84
80
76
72
68
64
60
56
0
20
40
60
80
100 120 140 160 180 200 220 240 260 280 300 320 340 360 380 400 420 440
Horizontal distance (ft)
Figure 4. A comparison of longitudinal profile surveys completed in Upper Williams Canyon. Cross-section intersections are indicated by the white triangles.
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Upper Williams Canyon Cross-Section #1
Cross-section #1 is located approximately 220 feet upstream of the upper-most sediment detention basin in the Williams Canyon reach. This
cross-section was established above the heavy machinery work to see what the natural channel processes may be. Cross-section #1 was
surveyed in June, July, August, and October, 2014. The June profile served as the baseline measurement. The thalweg elevation was recorded at
90.75 feet in June, 90.03 feet in July, 90.32 feet in August, and 91.48 feet in October indicating an overall pattern of aggradation of approximately
1.45 feet in this section of the reach (Figure 7). Overall the cross-section data show little change to the morphology of the stream during the study
period with regard to bank location and width of channel. Cross-section geometry remained fairly stable throughout the duration of the monitoring
period with no indication of narrowing or widening and little or no active bank erosion. Photographs taken at this cross-section visually support the
general pattern of aggradation observed at this portion of the reach throughout the monitoring period (Figure 8).
Upper Williams: Cross Section 1, 2014
106
Elevation (ft)
102
98
06/27/2014
94
07/19/2014
08/04/2014
90
10/18/2014
86
0
4
8
12
16
20
24
28
32
36
40
44
48
Horizontal distance (ft)
52
56
60
64
68
72
76
80
84
Figure 7. Summary of surveys at cross-section #1 in Upper Williams Canyon.
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Upper Williams Canyon Cross-Section #2
Cross-section #2 is located approximately 80 feet upstream of the upper-most sediment detention basin
in the Williams Canyon reach. This area was established at the beginning of heavy machinery work,
where the intermittent stream approaches the wider valley. This cross-section spanned over 200 feet to
allow surveying of both the channel and the decommissioned road utilized in the construction of the basin.
A single thread “B” channel begins approximately 33 feet from the left pin and is approximately 15 feet
wide and 8 feet deep. Cross-section #2 was surveyed in June, July, August, and October, 2014. The June
profile served as the baseline measurement. The thalweg elevation was recorded at 68.90 feet in June,
68.76 feet in July, 68.77 feet in August, and 68.92 feet in October indicating minimal aggradation or
degradation in this section of the reach (Figure 9). There appears to be some localized downcutting along
the left edge of the gully. Overall the cross-section data show little change to the morphology of the
stream during the study period with regard to bank location and width of channel. Cross-section geometry
remained fairly stable throughout the duration of the monitoring period with no indication of narrowing or
widening and minor active bank erosion. Photographs taken at this cross-section visually support the
overall stability observed at this portion of the reach throughout the monitoring period (Figure 10).
.
15
Upper Williams: Cross Section 2, 2014
06/26/2014
100
07/21/2014
95
08/04/2014
10/18/2014
Elevation (ft)
90
85
80
75
70
65
0
10
20
30
40
50
60
70
80
90
100
110
120
130
140
150
160
170
180
190
200
210
Horizontal distance (ft)
Figure 9. Summary of surveys at cross-section #2 in Upper Williams Canyon.
16
Upper Williams Canyon Cross-Section #3
Cross-section #3 is located across the upper-most sediment detention basin in the Williams Canyon
reach. This cross-section was established to monitor change in sedimentation of the basin with
corresponding storm events. This basin was quite deep and very hard to measure the complete crosssection until some aggradation had occurred. Cross-section #3 was surveyed in June, July, August, and
October, 2014. The June profile served as the baseline measurement. The thalweg elevation was
recorded at 80.28 feet in June, 82.71 feet in July, 82.81 feet in August, and 84.50 feet in October
indicating a clear pattern of aggradation of approximately 4.22 feet in this section of the reach (Figure 11).
Approximately 4.63 inches of rain fell in the area in July 2014, 2.34 inches fell in August 2014, and 2.96
inches fell in October 2014. Data suggest the sediment detention basin is functioning properly to capture
upstream sediment and slow water flows. Overall the cross-section data show little change to the
morphology of the stream during the study period with regard to bank location and width of channel.
Cross-section geometry remained fairly stable throughout the duration of the monitoring period with no
indication of narrowing or widening and minor active bank erosion. Photographs taken at this crosssection visually support the filling of the sediment detention basin and overall stability observed at this
portion of the reach throughout the monitoring period (Figure 12).
17
Upper Williams: Cross Section 3, 2014
102
06/27/2014
07/21/14
Elevation (ft)
98
08/04/2014
10/18/2014
94
90
86
82
78
0
10
20
30
40
50
60
70
80
90
Horizontal distance (ft)
100
110
120
130
140
150
Figure 11. Summary of surveys at cross-section #3 in Upper Williams Canyon.
18
Upper Williams Canyon Cross-Section #4
Cross-section #4 is located approximately 83 feet below the outlet sill of the sediment detention basin surveyed in cross-section #3. This crosssection was established in a broad “D” channel across a relatively wide channel. This cross-section is monitoring the continued deposition of flood
material and the re-establishment of a “B3” channel. Cross-section #4 was surveyed in June, July, August, and October, 2014. The June profile
served as the baseline measurement. The thalweg elevation was recorded at 94.88 feet in June, 94.15 feet in July, 94.78 feet in August, and 94.38
feet in October indicating minimal overall degradation of approximately 0.73 feet in this section of the reach (Figure 13). However, in specific
locations of the cross-section, more severe amounts of degradation are observed, particularly 30 feet from the left pin where active downcutting of
approximately 2 feet seems to be occurring within the stream channel. This is the “D” type braided stream re-establishing a single thread “B”
channel and concentrating flow and energy. Throughout the project area, it is observed that on the receding limb of the hydrograph, a single thread
channel is formed, but during the rising limb and during flood flows, the entire floodplain is accessed. The channel formation appears to increase
with time and corresponds to the detention basin upstream filling with sediment. When water is released from a sediment detention basin without
the sediment, channel and bank erosion often occurs downstream. The ongoing monitoring will help determine the long-term effects of clean water
discharge and channel stability. The minor erosion that is occurring downstream of the basin is indicative of the basin functioning properly to retain
sediment. Overall, the cross-section data show little change to the morphology of the stream during the study period with regard to bank location
and width of channel. Photographs taken at this cross-section visually support the relative stability in cross-section geometry at this portion of the
reach throughout the monitoring period (Figure 14).
Upper Williams: Cross Section 4, 2014
104
06/27/2014
07/21/2014
08/04/2014
102
10/18/2014
Elevation (ft)
100
98
96
94
92
0
10
20
30
40
50
60
Horizontal distance (ft)
70
80
90
100
Figure 13. Summary of surveys at cross-section #4 in Upper Williams Canyon.
19
Figure 14. Photos at cross-section #4 below the sediment detention basin looking downstream in Upper Williams Canyon. Photo
on left taken 07/21/2014; photo on right taken 10/18/2014. Note longitudinal profile and single thread channel forming and with
floodplain access.
Summary of Monitoring Questions for Upper Williams
•
Did the structures function as designed and help to store and spread sediment across the floodplain?
a. Data suggest the sediment detention basin is functioning properly to capture upstream sediment and slow water flows.
b. Channel forming processes and adjustments are observed below the sediment detention basin as a new, intermittent steam
channel is established. These are areas that will be monitored in 2015 to determine trends.
•
Was there damage to the structures? If so, are additional treatments necessary?
a. There were no damages to the structures and no additional treatments are necessary.
•
What type of storm events did the structure receive prior to monitoring/during monitoring?
a. Between the monitoring period of June-October 2014, this area received approximately 11.83 inches of rain.
•
Are there indicators of channel downcutting? If so, are more structures needed?
a. There is minimal indication of channel downcutting; no additional structures are needed.
20
Lower Williams
Longitudinal Profile
The longitudinal profile survey at the Lower Williams Canyon reach was approximately 220 feet (67.1 meters) in length (Figure 15) and was
measured down the center of an unnamed tributary to Williams Creek; the longitudinal profile ended at the confluence of the tributary and Williams
Creek. The average overall slope of the reach was 8.62%. Comparison of the three post-storm longitudinal profiles revealed a general and
consistent pattern of degradation along the entire reach of approximately 0.5 to 1.0 foot. Photographs taken at the start of the longitudinal profile
(Figure 16) visually support the general pattern of degradation observed along the reach throughout the duration of the monitoring period.
Lower Williams: Longitudinal Profile 2014
102
07/28/2014
08/05/2014
Elevation (ft)
98
10/18/2014
94
90
86
82
78
0
20
40
60
80
100
120
Horizontal distance (ft)
140
160
180
200
220
Figure 15. Summary of longitudinal profile surveys conducted at Lower Williams Canyon. Cross-section intersections are indicated by the white triangles.
21
Figure 16. Photos at beginning of longitudinal profile (cross-section #1) looking downstream in Lower Williams Canyon. Photo on left
taken 08/04/2014; photo on right taken 10/18/2014. Note vegetation being re-established at the edge of a new bankfull channel that
is starting to form.
Lower Williams Canyon Cross-Section #1
Cross-section #1 is located in an ephemeral drainage, approximately 185 feet upstream of the confluence of the tributary with Lower Williams
Creek. This cross-section is a confined channel upstream of the re-constructed alluvial fan. This cross-section was established to monitor the
natural recovery of an ephemeral drainage. Cross-section #1 was surveyed two times in July, once in August, and once in October, 2014. The first
July survey served as the baseline measurement. The thalweg elevation was recorded at 88.42 feet on July 7, 88.84 feet on July 28, 88.71 feet on
August 5, and 88.57 feet on October 18 indicating relative stability in stream channel elevation in this section of the reach (Figure 17). At station
25, bank erosion on the left side of the channel is resulting in an approximate 5-foot drop in elevation. Approximately 4.63 inches of rain fell in the
area in July 2014, 2.34 inches fell in August 2014, and 2.96 inches fell in October 2014. Overall, the cross-section data show little change to the
22
morphology of the stream during the study period with regard to bank location and width of channel. Photographs taken at this cross-section
visually support the bank erosion occurring on the left side of the channel and the relative stability in cross-section geometry observed at this
portion of the reach throughout the monitoring period (Figure 18).
Lower Williams: Cross Section 1, 2014
100
07/07/2014
07/28/2014
08/05/2014
10/18/2014
98
Elevation (ft)
96
94
92
90
88
86
0
5
10
15
20
25
30
Horizontal distance (ft)
35
40
45
50
Figure 17. Summary of surveys at cross-section #1 in Lower Williams Canyon.
23
Lower Williams Canyon Cross-Section #2
Cross-section #2 is located approximately 75 feet upstream of the confluence of the ephemeral tributary
and Lower Williams Creek. This is where the tributary channel widens as storm flows access the newly
reconstructed floodplain. The cross-section was established to see how well the constructed fan with log
sills receives and handles storm flows. Cross-section #2 was surveyed two times in July, once in August,
and once in October, 2014. The first July survey served as the baseline measurement. The thalweg
elevation was recorded at 95.27 feet on July 7, 94.72 feet on July 28, 94.76 feet on August 5, and 94.74
feet on October 18 indicating a general pattern of single thread channel formation (Figure 19). Between
July 6-12, approximately 0.65 inches of rain fell on the area; between July 27-August 2, approximately
1.74 inches of rain fell on the area; and between October 5-11, approximately 2.96 inches of rain fell. The
most significant adjustment occurs between the July 7 (blue line) and July 28 (magenta line)
measurements. Also worth noting is the clear change in bed material composition and size. This is a
strong indicator that the floodplain functioned well at the peak of the hydrograph and that flood flows
dispersed energy and large size material was deposited with very little downcutting occurring on the
receding limb of the hydrogaph. Overall, the cross-section data show little change to the morphology of
the stream during the study period with regard to bank location and width of channel. Photographs taken
at this cross-section visually support these observations (Figure 20).
24
Lower Williams: Cross Section 2, 2014
07/07/2014
07/28/2014
08/05/2014
10/18/2014
Elevation (ft)
100
98
96
94
0
10
20
30
40
Horizontal distance (ft)
50
60
70
80
Figure 19. Summary of surveys at cross-section #2 in Lower Williams Canyon
25
Lower Williams Canyon Cross-Section #3
Cross-section #3 is located approximately 30 feet upstream of the confluence of the tributary and Williams
Creek. Cross-section #3 was surveyed two times in July, once in August, and once in October, 2014. The
first July survey served as the baseline measurement. The thalweg elevation was recorded at 94.79 feet
on July 7, 94.21 feet on July 28, 94.65 feet on August 5, and 94.91 feet on October 18 indicating very
minimal aggradation or degradation in this section of the reach (Figure 21). Overall, the cross-section
data show little channel adjustment during the study period with regard to bank location and width of
channel. Cross-section geometry and channel morphology remained stable throughout the duration of the
monitoring period with no indication of narrowing or widening and minor active bank erosion. Photographs
taken at this cross-section clearly show a marked change in the composition of streambed materials
(Figure 22). Baseline observations indicate streambed materials comprised of very coarse gravel to small
cobbles while observations at the end of the monitoring period indicate streambed materials comprised of
large cobbles to large boulders. This is indicative of the reconstructed floodplain lowering energy and
depositing large materials at the end of the reach near the confluence with Williams Creek.
26
Lower Williams: Cross Section 3, 2014
07/07/2014
07/28/2014
08/05/2014
10/18/2014
102
100
Elevation (ft)
98
96
94
92
90
88
0
10
20
30
40
50
60
70
80
90
Horizontal distance (ft)
100
110
120
130
140
150
Figure 21. Summary of surveys taken at cross-section #3 in Lower Williams Canyon.
27
Summary of Monitoring Questions for Lower Williams
•
Did the structures function as designed and help to store and spread sediment across the floodplain?
a. Data suggest the reconstructed floodplain at the end of the monitoring reach is
functioning to dissipate energy and deposit large materials near the confluence with
Williams Creek.
•
Was there damage to the structures? If so, are additional treatments necessary?
a. There were no damages to the structures and no additional treatments are necessary.
•
What type of storm events did the structure receive prior to monitoring/during monitoring?
a. Between the monitoring period of June-October 2014, this area received approximately
11.83 inches of rain.
•
Are there indicators of channel downcutting? If so, are more structures needed?
a. There is minimal indication of channel downcutting along the reach; no additional
structures are needed.
Wellington Gulch
Longitudinal Profile
The longitudinal profile survey at the Wellington Gulch reach was approximately 300 feet (91.4 meters) in
length (Figure 23). This profile started in the ephemeral drainage above an empty sediment detention
basin and was carried through the basin and downstream of the basin. Preconstruction, this portion of
Wellington Gulch had already eroded down approximately 10 feet and a new “D” channel was reestablished. Where the basin had ponded water that was too deep and above the rod, measurements
were not taken. The average overall slope of the reach was 12.44%. Measurements were taken in July,
August, and October, 2014. Comparison of the three post-storm measurements revealed a general
pattern of degradation along first third of the reach. Photos taken at the beginning of the longitudinal
profile looking downstream reveal the occurrence of many small rills cutting shallow channels in the
streambed indicating that the flood flows are spread across the valley, the sills are functioning, and water
is not becoming concentrated and causing erosion (Figure 24). Between stations 180 and 220 (the
sediment detention basin), a pattern of aggradation is observed as the basin fills with sediment. No
additional rilling or bank erosion are observed below the sediment detention basin, indicating the basin is
functioning to trap sediment and minimize the velocity of water flow (Figure 25).
28
Wellington Gulch: Longitudinal Profile 2014
102
98
94
90
86
82
78
74
70
66
62
58
Elevation (ft)
07/22/2014
08/06/2014
10/21/2014
0
20
40
60
80
100
120
140
160
180
Horizontal distance (ft)
200
220
240
260
280
300
Figure 23. Summary of longitudinal profile surveys conducted in Wellington Gulch.
29
Wellington Gulch Cross-Section #1
th
Cross-section #1 is located across the 4 sediment detention basin in the upper Wellington Gulch reach.
This cross-section was established to determine the accumulation of sediment in the detention basin.
Cross-section #1 was surveyed July, August, and October, 2014. The thalweg elevation was recorded at
76.99 feet in July, 79.82 feet in August, and 82.35 feet in October indicating a clear pattern of sediment
deposition of approximately 5.36 feet in this section of the reach (Figure 26). Data suggest the sediment
detention basin is functioning properly to capture upstream sediment and slow water flows. The October
measurements indicate active bank erosion on the left side of the basin looking downstream. This is a
function of the method of construction. Once the basin is full, it is expected that a stable angle of reposed
will be established and contributions from the side of the basin will be reduced. Overall the cross-section
data show little change to the morphology of the stream during the study period with regard to bank
location and width of channel. Cross-section geometry remained fairly stable throughout the duration of
the monitoring period with minimal indication of narrowing or widening and minor active bank erosion.
Photographs taken at this cross-section visually support the filling of the sediment detention basin and
overall stability observed at this portion of the reach throughout the monitoring period (Figure 27).
30
Wellington Gulch: Cross Section, 2014
07/22/2014
08/06/2014
10/21/2014
100
Elevation (ft)
96
92
88
84
80
76
0
10
20
30
40
50
60
Horizontal distance (ft)
70
80
90
100
Figure 26. Summary of surveys taken at cross-section #1 in Wellington Gulch.
31
Summary of Monitoring Questions for Wellington Gulch
•
Did the structures function as designed and help to store and spread sediment across the floodplain?
a. Data suggest the sediment detention basin is functioning properly to capture upstream
sediment and slow water flows.
•
Was there damage to the structures? If so, are additional treatments necessary?
a. There were no damages to the structures and no additional treatments are necessary.
•
What type of storm events did the structure receive prior to monitoring/during monitoring?
a. Between the monitoring period of June-October 2014, this area received approximately
11.83 inches of rain.
•
Are there indicators of channel downcutting? If so, are more structures needed?
a. There is minimal indication of channel downcutting along the reach; no additional
structures are needed.
Camp Creek
Photopoint #1: Sediment Detention Basin
Photographs taken at the sediment detention basin in Camp Creek reveal the basin is functioning
properly to capture sediment-laden runoff originating upstream (Figure 28). There is also some evidence
of increased erosion at the outlet sill of the basin, which is concentrating flow into a single thread channel.
The outflows should be uniform across the sill and a weak spot was found. The sill and downstream of the
basin should be monitored for risk of increased erosion. Photos also indicate establishment of vegetation
on banks adjacent to the basin as well as on hillslopes surrounding the basin. Native species
establishment will help secure hillslopes and the banks of the basin to minimize further sediment transport
downstream.
32
Photopoint #2: Decommissioned Road
In the fall of 2013, the road used to construct the sediment detention basin was decommissioned,
including recontouring a temporary benched in road. The area was reseeded with native vegetation, and
snags found on-site were positioned along the contour of the slope to reduce water velocity, break up
concentrated flows, and induce hydraulic roughness to the burned soil surface. In some instances, rocks
were placed behind the snags to further stabilize the area and minimize downcutting. Photographs taken
at the site indicate both the snags and reseeding efforts were successful in restoring the road and
stabilizing the hillslope (Figure 29).
Figure 29. Photos at the top of the decommissioned road above the sediment detention basin in Camp Creek. Photo on left taken
07/01/2014; photo on right taken 08/06/2014. Note vegetation growth on hillslope and effectiveness of snags at slowing water flows
and stabilizing the hillslope.
Photopoint #3: Log-Erosion Barriers Adjacent to Sediment Detention Basin
During construction of the sediment detention basin, active rill erosion was occurring in an area adjacent
to the right bank of the basin. In the fall of 2013, ten log-erosion barriers measuring approximately 4 to 10
feet in length were installed perpendicular to the area of rill erosion. The area was also seeded with native
vegetation. Photos taken at the site indicate both the log-erosion barriers and reseeding efforts were
successful in stabilizing the area and preventing further erosion of the rill (Figure 30).
Figure 30. Photos at the bottom of the decommissioned road along the right bank of the sediment detention basin in Camp Creek.
Photo on left taken 07/01/2014; photo on right taken 10/21/2014. Note vegetation growth behind the log-erosion barriers and
sediment aggradation behind the lowermost log.
33
Photopoint #4: Outlet Sill of Sediment Detention Basin
The outlet sill of the detention basin was monitored to ensure its capacity to slowly discharge water
spread across the length of the sill without further contributing to downstream erosion. Photographs taken
at the site indicate no active erosion was occurring at the sill and native vegetation was establishing itself
below the sill, further stabilizing the area and allowing for a mechanism to filter and slow water flows
(Figure 31).
Figure 31. Photos taken at the outlet sill of the sediment detention basin in Camp Creek. Photo on left taken 07/01/2014; photo on
right taken 10/21/2014. Note vegetation growth behind the sill and lack of active downstream erosion.
Summary of Monitoring Questions for Camp Creek
•
Did the structures function as designed and help to store and spread sediment across the floodplain?
a. Repeated photographs show the sediment detention basin is functioning properly to
capture upstream sediment and slow water flows.
b. Log-erosion barriers and reseeding efforts were successful in stabilizing the area and
preventing further erosion of the rill.
c. Photographs taken at the site indicate both the snags and reseeding efforts were
successful in restoring the road and stabilizing the hillslope.
•
Was there damage to the structures? If so, are additional treatments necessary?
a. There is evidence of increased erosion at the outlet sill of the basin, which is
concentrating flow into a single thread channel. The sill and downstream of the basin
should be monitored for risk of increased erosion.
•
What type of storm events did the structure receive prior to monitoring/during monitoring?
a. Between the monitoring period of June-October 2014, this area received approximately
11.83 inches of rain.
•
Are there indicators of channel downcutting? If so, are more structures needed?
a. There is minimal indication of channel downcutting; no additional structures are needed.
34
COMPILATION OF MONITORING AND RESEARCH EFFORTS IN THE WALDO CANYON BURN
SCAR
Implementation of emergency stabilization treatments in the Waldo Canyon burn scar have been
numerous as well as research and monitoring efforts assessing the effectiveness of the treatments. The
U.S. Forest Service partnered with the Rocky Mountain Field Institute to compile and summarize all
monitoring and research activities occurring within the burn scar to enhance collaboration and inform
future restoration work. This document comprises an explanation and summary of research/monitoring
activities conducted, or being conducted, by various stakeholder groups involved in the recovery of the
Waldo Canyon burn scar.
CITY OF COLORADO SPRINGS – OFFICE OF EMERGENCY MANAGEMENT
The City of Colorado Springs contracts with the U.S. Geological Survey to maintain three rain gages on
the Waldo Canyon Burn Scar area. The gages are located at a Colorado Springs Utilities water storage
tank in Mountain Shadows, a location near Ormes Peak above Rampart Range Road, and approximately
3 miles upstream of Glen Eyrie in Queen’s Canyon. These rain gages are monitored on a regular basis.
In addition, flood and sediment mitigation structures were installed in 2013 on the Flying W Ranch (North
and South Douglas Creeks) and The Navigators at Glen Eyrie and Garden of the Gods Park (Camp
Creek). These structures are also monitored on a regular basis.
Precipitation amounts in 2014 were much lower on North Douglas and Camp Creek as compared to
amounts in 2013. Structures were also capturing large quantities of sediment and controlling high stream
flows. In North Douglas Creek, a new 16,000 cubic yard basin was constructed in 2014 after midSeptember 2013 storms buried Basins 1 through 3 and severely damaged Basins 4 & 5 (an estimated
60,000 cubic yards moved down the drainage). The new basin will need to be cleared in preparation for
the 2015 monsoon season. A tertiary drainage on North Douglas Creek (DC-006) that confluences with
the main channel near Basins 1 & 2 is also being monitored. Two in-channel basins and numerous sillwall structures were installed in the drainage in 2014 to slow water flows and capture sediment, but a
significant amount of sediment has staged upstream of the basins, and it is likely the area will be
inundated during the next large rain event.
In South Douglas Creek, flash flooding continued to damage the roads and terrain upstream of the Flying
W Chuckwagon area. Log erosion barriers and reseeding efforts implemented above the alluvial fan have
not been as successful in mitigating sediment movement. Once the mountain slopes upstream have
completely revegetated, the area should begin to see some stabilization. Five sediment detention basins
installed in 2013 continued to capture sediment.
A sediment detention basin was installed and the channel modified in the west channel of South Douglas
Creek in 2013. In the spring of 2014, diffusers were installed to help reduce the velocity of water flowing
down the channel. During a July 2014 rainstorm, the diffusers were overwhelmed by they stream flow and
the basin overtopped and send floodwaters downstream. The basin will need to be cleared in preparation
for the 2015 monsoon season.
The Geobrugg Nets, installed by The Navigators in 2013, performed as designed in 2014. The lower net
held sediment and will be cleared by City Public Works before the 2015 monsoon season. The
35
Navigators, working with Wilson and Company Engineering Inc., redesigned the Camp Creek channel
through Glen Eyrie. The new channel is straighter and armored with boulders and concrete. Seven small
bridges were replaced with large bridges, or eliminated, to allow the water to more readily flow and enable
the structures to withstand the pressure from high flood events. The channel is being armored all the way
to the new catchment basin in Garden of the Gods Park and should be complete in January 2015.
At the northeast corner of Garden of the Gods Park, a large sediment catchment basin was constructed in
the location of a very large sediment deposition that occurred during the September 2013 rains near 30th
Street. The 16,000 cubic yard catchment basin is designed to remove sediment and allow water to flowout; it is expected to have very little water during most of the year. Like the basins on North Douglas and
South Douglas Creeks, the Camp Creek basin is designed to be maintained by removing accumulated
sediment.
Links:
https://drive.google.com/open?id=0B_HIEohsaTRvaU5BQTgxRmtlVXc&authuser=0
https://drive.google.com/open?id=0B_HIEohsaTRvQ3hqdU8zWTZmZzg&authuser=0
Contact:
Gordon Brenner
City of Colorado Springs, Office of Emergency Management
Fire Recovery Coordinator
375 Printers Parkway
Colorado Springs, CO 80910
Phone: 719-385-5957
Email: [email protected]
COALITION FOR THE UPPER SOUTH PLATTE
The Coalition for the Upper South Platte (CUSP) is part of a larger coalition of government agencies,
communities, private landowners, contractors, consultants and other nonprofits that came together to
address post-wildfire concerns and flooding. CUSP created a story map with information from partners to
provide a visual representation of all the rehabilitation work being implemented in and around the Waldo
Canyon burn scar. The fire impact and recovery map details affected communities, sub-watersheds, and
drainages; results from the Watershed Assessment of River Stability and Sediment Supply (WARSSS)
study; community outreach activities; and fire restoration treatments (early warning rain gauges, sediment
detention basins, grade control structures, channel stabilization/restoration structures, crib walls, logerosion barriers, jute matting, wattles).
Contact:
Carol Ekarius
Executive Director
Coalition for the Upper South Platte
38000 Cherokee Avenue
P.O. Box 726
Lake George, CO 80827
Phone: 719-748-0033
Email: [email protected]
36
Link:
http://waldofire.org/map/
COLORADO SCHOOL OF MINES
The Hogue Research Team is investigating short- and long-term hydrologic response in the Waldo
Canyon Fire area and the impacts that post-fire climatology, treatment, burn severity, geophysical
parameters, and vegetation dynamics have on post-fire recovery. The group ultimately hopes to improve
insight on hazard mitigation at the urban fringe and advance management and resource decisions after
fire.
Link:
http://inside.mines.edu/~thogue/research/wildfire.html
Contact:
Terri Hogue, Ph.D.
Associate Professor
Colorado School of Mines
Department of Civil & Environmental Engineering
1500 Illinois Street
Golden, CO 80401
Phone: 303-384-2588
Email: [email protected]
COLORADO SPRINGS UTILITIES
As of December 2013, approximately 30 acres of hillslope stabilization and 104 acres of seeding have
been completed in the Northfield and Devil’s Kitchen drainages. Hillslope stabilization primarily consisted
of log-erosion barriers (LEB), which are contour felled trees bedded and staked to offer a barrier to sheet
flow erosion as well as rill formation. There is controversy in research literature around the effectiveness
of LEB treatments to trap quantities of sediment that benefit downstream water quality concerns.
Furthermore, many land managers do not promote LEB treatments because of the cost and expertise
needed to ensure proper installation. If LEB installation is not done appropriately they can concentrate
flows and therefore increase the rate of rill formation. As part of Utilities monitoring program two potential
benefits to LEB treatments will be explored. First, monitoring will be conducted to understand the rate,
density, and morphology of rills in LEB units versus untreated units. The second goal of monitoring will be
surveying vegetation recovery in an LEB unit versus untreated unit. All monitoring will take place once per
year for 3 years. Monitoring results from May 2014 indicate vegetation recovery has been faster in LEB
units than non-LEB units. In addition, rill development was not observed in LEB units while 4 rills were
observed in the non-LEB unit.
Links:
http://krcc.org/post/utilities-mitigation-work-northfield-watershed-nearly-complete
http://gazette.com/colorado-springs-utilities-happy-with-post-waldo-mitigation-work/article/1505197
37
Contact:
Kim Gortz
Program Manager, Source Water Protection
Colorado Springs Utilities
Phone: 719-668-8030
Email: [email protected]
U.S. AIR FORCE ACADEMY
Waldo Canyon fire environmental effects monitoring: Environmental effects on drainage structures and
systems resulting from the Waldo Canyon Fire on the U.S. Air Force Academy (USAFA) are being
monitored through several research studies. Diane Strohm met with a team from UC Denver along a
100’ reach of a West Monument Creek tributary, collecting baseline data on stream morphology, aquatic
organisms, pH, and pebble size. Numerous sites throughout and below the burn area will be monitored, in
addition to control plots which were unaffected by the fire.
Diane Strohm completed a contract for forestry restoration work in the Waldo Canyon Fire burn area. This
project included removing downed trees and chipping piles of woody debris to reduce potential fuel
hazard and minimize Ips beetle infestation. Attracted to stressed, dying or recently dead trees, Ips
populations can build up and spread to adjacent healthy trees. The area will be monitored again next
month and in early spring.
In addition, USAFA Lieutenant, Brett Brunner, and Stanley Rader published an article in the The
Homeland Security Review; A Journal of the Institute for Law & Public Policy, titled "Wild Fire Impact on
Stormwater Runoff - The Waldo Canyon Fire Legacy" (Volume 8, No. 1, Winter 2014, California
University of Pennsylvania). In the article, the authors summarized efforts to hydrologically model the
Camp Creek drainage basin for pre-fire and post-fire storm runoff. The authors concluded that the
estimated post-fire discharge at the mouth of Queen's Canyon for a 100-year storm today is 2.4 times
greater than the predicted storm runoff volume prior to the fire.
Contacts:
Diane Strohm
Natural Resource Manager
Colorado Fish and Wildlife Conservation Office
United States Air Force Academy
Colorado Springs, CO
Phone: 719-333-3308
Email: [email protected]
Stanley Rader
Associate Professor
Department of Civil and Environmental Engineering
United States Air Force Academy
Colorado Springs, Co
Phone: 719-333-7471
Email: [email protected]
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U.S. FOREST SERVICE
Production and aerial application of wood shreds as a post-fire hillslope erosion mitigation treatment
At the 2012 Waldo Canyon Fires in Colorado, a contractor produced and distributed nearly 11,750 tons
(10,660 metric tons) of wood shred mulch on 1,960 ac (793 ha) of steep mountainous landscape (20 to 60
percent slopes) burned at moderate and high burn severity. The contractor obtained wood shreds from
four sources (burned roadside hazard trees and green trees from a fuel break construction, a stewardship
area project, and a local timber products stock yard) and applied the mulch using up to five helicopters
equipped with cargo nets. Because wood shreds are four to six times heavier than agricultural straw,
wood shred mulch took longer to apply than agricultural straw for the same area (25 to 35 ac [10 to 14 ha]
per day for wood shreds; approximately 200 ac [81 ha] per day for straw). The additional flight time makes
mulching with wood shreds cost three to four times more than with agricultural straw ($1700 to $2200 per
ac [$4200 to $5500 per ha] for wood shreds; $500 to $700 per acre [$1200 to 1700 per ha] for straw).
However, the advantages of wood shreds—on- or near-site availability, greater stability in high winds and
on steep slopes, and lack of unwanted plant seeds from off-site—make wood shred mulch useful in areas
where agricultural straw mulch may not be desirable.
Link:
http://www.fs.fed.us/rm/pubs/rmrs_gtr307.pdf?
UNIVERSITY OF COLORADO – DENVER
Research Objectives: track changes in topography, stream channel morphology, sediment dynamics, and
ecological conditions in response to precipitation events and related post-fire flooding
Study Sites:
• Williams Canyon: 3 sites
• Camp Creek: 5 sites
Timeframe of sample collection:
• 2012 Fall
• 2013 Spring, Summer, Fall
• 2014 Spring, Summer, Fall
Data collected:
Topography
Terrestrial LiDAR images
Channel Morphology
Longitudinal profiles
Cross sections
Sediment
Pebble counts
Bulk samples
Ecology
Benthic macroinvertebrate samples
39
Precipitation
Rainfall data from 4 tipping bucket gages along Rampart
Range Road (2013 and 2014 only)
Summary of findings to date (analysis ongoing):
• Storms in 2013 produced extensive morphologic change in channels of Williams Canyon
(degradation of up to one meter), accompanied by drastic reduction of benthic communities.
• By summer 2014, channels began to reestablish natural step-pool structure, with corresponding
changes to benthic communities.
• Channel morphology and ecology were less severely impacted in Camp Creek.
Links:
•
•
Geological Society of America 2013
https://gsa.confex.com/gsa/2013AM/webprogram/Paper230047.html
•
•
American Geophysical Union 2013*
http://adsabs.harvard.edu/abs/2013AGUFMEP53A0722C
•
•
American Geophysical Union 2014*
https://agu.confex.com/agu/fm14/meetingapp.cgi#Paper/26144
•
•
American Geophysical Union 2014
https://agu.confex.com/agu/fm14/meetingapp.cgi#Paper/26116
Contact:
Anne Chin, PhD
Professor
University of Colorado – Denver
Department of Geography and Environmental Sciences
Denver, CO 80218
Phone: 303-556-2823
Email: [email protected]
Sponsors
Data collection and analysis for this project have been possible through research grants from the National
Science Foundation (EAR1254989) and the University of Colorado Denver, partnership with the U.S.
Geological Survey (that provided use of rain gauges), and generous logistical support from The
Navigators, U.S. Air Force Academy, and the U.S. Forest Service.
40
41
42
VIRGINIA TECH UNIVERSITY
A ridge in the Jetstream (upper air winds) brought hot and dry continental air from the south to the
Colorado area, and then the pattern stalled throughout most of the lifespan of the fire. Dew point
temperatures, the temperature in which the air temperature must drop to in order to reach saturation, was
in the single digits to teens while the air temperature was breaking past 100F. The winds were the main
contributor to the direction and the strength of the fire spread. 2012 was a very hot and dry summer,
followed by a very dry winter. The dry winter did not help the area preventing a massive drought in the
west-central United States. Summer 2012 set records in both heat and drought that lead up to over 10
wildfires throughout Colorado. Other parts of the United States experienced very dry and hot summers
too. For example, a derecho, a very intense line of storms that originated in Iowa on June 29, 2012,
moved very quickly to the eastern seaboard which was caused by extremely high temperatures. In the
initial days of the fire, mainly the 23rd and 24th, the fire had a broad mix of shrub-land and Evergreen
forests to help the spread of the fire. It should also be noted that due to the extreme drought conditions,
and winds, these lands were very susceptible to rapid fire spreading. As the fire spread Northwest, the
predominant fuel source were the Evergreen and Deciduous forests, which are to be considered a strong
fuel source to fuel a forest fire. It is currently unknown what actually caused the Waldo Canyon Fire,
whether it be dry thunderstorms or arson, is still under investigation. The area is slowly recovering and will
take many years to return back to before the fire. The areas that were low burned areas are starting to
see grass and yucca growths, while the more scarred areas are slower to recover.
Contact:
Mario Garza
Virginia Tech University
Geography Department
115 Major Williams Hall
Blacksburg, VA 24061
Phone: 540-231-6886
Link:
https://vtechworks.lib.vt.edu/handle/10919/50689
43
REFERENCES
Hall, F. 1997. Ground-based photographic monitoring. Natural Resources Unit, Pacific Northwest Region,
USDA Forest Service, Portland, Oregon.
Harrelson, C.C., C.L. Rawlins, and J.P. Potyondy. 1994. Stream channel reference sites: An illustrated
guide to field technique. Gen. Tech. Rep. RM-245. Fort Collins, Colorado: U.S. Department of
Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment Station. 61 p.
Rosgen, D.L., and H.L. Silvey. 1996. Applied River Morphology. Wildland Hydrology Books, Fort Collins,
Colorado.
Rosgen, D.L., B. Rosgen, S. Collins, J. Nankervis, and K. Wright. 2013. Waldo Canyon Fire Watershed
Assessment: The WARSSS Results. Wildland Hydrology, Fort Collins, Colorado.
Rosgen, D.L., B. Rosgen, S. Collins, and J. Nankervis. 2013. The Waldo Canyon Fire Master Plan for
Watershed Restoration & Sediment Reduction. Wildland Hydrology, Fort Collins, Colorado.
ACKNOWLEDGMENTS
RMFI would like to thank the U.S. Forest Service for helping develop monitoring protocols, participating in
data collection, and facilitating data processing and analysis. RMFI would also like to thank Jaxon Rickel,
RMFI Intern, and Julie Mazzola, RMFI Research Assistant, for their help in data collection.
44
APPENDIX A
Summary of Sub-Watershed Characteristics
45
46
47
APPENDIX B
Monitoring Locations in Williams Canyon, Wellington Gulch, and Camp Creek Sub-Watersheds
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