16LA-LAIR01 FIRE
June 2, 2016
Case Study:
How Fuel Treatment Areas Affect Wildland Urban Interface Fires
Saskatchewan.ca/fire
Contents
Introduction .................................................................................................................................................. 3
Fire History .................................................................................................................................................... 3
Weather Observations .................................................................................................................................. 4
Fuel Treatment Background ......................................................................................................................... 4
Wildfire Behaviour Analysis .......................................................................................................................... 5
Conclusion ..................................................................................................................................................... 8
Figure 1 - Photos taken after the fire was called out.................................................................................... 3
Figure 2 - Bird Dog photos of arrival on left and departure on right. ........................................................... 4
Figure 3 - Photos of treated area in the winter after thinning was complete and treated area after the
fire. ................................................................................................................................................................ 5
Figure 4 - Map of fire boundary .................................................................................................................... 5
Figure 5 - Map of Pegasus 12hr projection ................................................................................................... 6
Figure 6 - Scorch heights up to 86 cm within treated area........................................................................... 7
Figure 7 - Photo shows line of where treated and untreated fuels burnt .................................................... 7
Figure 8 - Untreated area on the left and treated area on the right. ........................................................... 9
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Introduction
The 16LA-LAIR01 fire was reported to the La Ronge Fire Base at 15:59 on June 2, 2016. The fire was
located on the Lac La Ronge Indian Band near Belles Point. The fire originated behind a row of houses
between Belles Point Road and Jimmy Roberts Road. The fire was mapped at 0.1 hectares, burnt in M2
boreal mixed wood green fuel and was started along the edge of a previously thinned fuel management
area.
Figure 1 - Photos taken after the fire was called out.
Fire History
The 16LA-LAIR01 Fire was reported by the public via phone to La Ronge Fire Base Supervisor John G Ross
at 15:59 on June 2 2016, he then dispatched the wildland firetruck and two Initial Attack crew members
to the fire. The La Ronge Regional Fire Department was also on site. Initial Attack Crew Member called
for air support as the fire was rank 3 and in immediate proximity to structures. Diverted from the 16LAHollow Fire at 16:04, Birddog #143 along with CL215T’s #216 and #217 were on site and completed the
first drop of foam at 16:13. The tankers dropped nine loads or 10,800 gallons of foam, with a turnaround
time of 2 min per drop, and were off the fire by 16:21. Two Initial attack members along with 4 type 2
personnel continued to work on the fire with one water pump and 15 hose lengths. At 17:17 the fire was
reported as contained to the La Ronge Fire Base. By 20:36 FSIN Crew leader Doug Ross said the fire was
contained and all fire equipment was removed. On June 3rd Initial Attack Crew Member Irvine Roberts
scanned the fire and found two hotspots. A sustained action crew worked on the two hotspots with
hand tools. The fire was scanned again and no hotspots were found. The fire was then later called out
on June 3rd. There were no spot fires observed from this fire. A fire investigation was requested and was
concluded that the fire was intentionally set yet no suspects have been found.
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Figure 2 - Bird Dog photos of arrival on left and departure on right.
Weather Observations
Recorded weather observations for the La Ronge weather station at 12:00 June 2nd 2016 were as
follows:
Temp
23
FFMC
87
RH
38
DMC
56
Wind Direction
SE
DC
ISI
180
7
Wind Speed
19
BUI
FWI
63
20
ROS M2 m/min
7
HFI (kW/m)
5341
CFB (%)
59.33
ROS C2 m/min
9
HFI (kW/m)
8314
CFB (%)
82.22
Fuel Treatment Background
Wildfire Management has had ongoing fuel management work completed within the Lac La Ronge
Indian Reserve since 2009. The area along the 16LA-LAIR01 Fire had been thinned in the winter of 2015.
This 5 hectare block was treated by the softwood being thinned out by hand crews to a crown spacing of
two meters and ladder fuels were removed up to two meters. All salvageable wood was stacked for
firewood and tops and limbs were piled and burnt on site.
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Figure 3 - Photos of treated area in the winter after thinning was complete and treated area after the fire.
Wildfire Behaviour Analysis
On June 7th Wildfire Prevention staff examined the fire area to collect information on fuel break
effectiveness. The crew members that responded to this fire were asked to provide information about
the fire behaviour and their thoughts on how the fuel management affected the fire. Initial attack
members stated that if this area was not previously thinned, the fire could have easily spread to nearby
homes and it would not have been as easy to access and suppress the fire. The fire was mapped at 0.1
hectares. With 0.07 ha of it being a surface fire that burned into the thinned area as seen in the map
below. The fire burnt along the edge of the thinned area and 15 meters into it.
Figure 4 - Map of fire boundary
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A Pegasus 1 Wildfire Projection was completed for this fire. The 12 hour projection shows the fire
burning an area up to 190 hectares, which covers many homes, a school and community center.
Figure 5 - Map of Pegasus 12hr projection
1
Pegasus is an online version of Prometheus that was developed by the Canadian Forest Service in collaboration with
Saskatchewan Ministry of Environment Wildfire Management Branch.
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Figure 6 - Scorch heights up to 86 cm within treated area
Figure 7 - Photo shows line of where treated and untreated fuels burnt
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Untreated plot
Black Spruce
Birch
Labrador Tea
Horsetail
Feather Moss
Height Class
Crown Separation
Crown Closure
Crown Base Height
4000 / ha
100 / ha
50%
50%
100%
15m
1m
70%
1m
Treated plot
Black Spruce
Birch
Labrador Tea
Horsetail
Feather Moss
Height Class
Crown Separation
Crown Closure
Crown Base Height
900 / ha
400 / ha
50%
50%
100%
15m
3m
50%
3m
A storm system was moving through the area at the time of the fire. As seen in the bird dog arrival
photo, rain showers and erratic winds had an effect on the direction of the fire. It is also noted that the
“Lake Effect” changed the wind direction between what had been observed at the La Ronge weather
station and at the fire which is 8.5km south of the weather station.
Conclusion
Although the fire behaviour was not extreme on the day of this fire, the thinned area still played a role
in the fire spread and effectiveness of containment. It was started in an untreated area and burnt along
the edge of the treated area; there is a distinct line of black where it crept along the ground in the
treated area. If this area was not previously treated the fire had potential to move closer to homes, yet
because of the thinned and pruned trees the fire was kept to a surface fire and did not advance in that
direction. The crew members that actioned this fire said that it was a lot easier to get suppression
equipment into the site and easier to maneuver around without all the understory and ladder fuel. It
was also noted that lower fire intensity and a transition to a surface fire supported the crew’s efforts to
contain the fire.
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Figure 8 - Untreated area on the left and treated area on the right.
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