Evaluating Winter Tundra Access Methods:
Research Conducted in the Mackenzie Delta
Julian Kanigan INACOverland Winter Access Workshop,
Inuvik, April 23-24, 2008
Outline1. Operational considerations
– Snow vs ice roads– Multiple seasons
2. Environmental considerations– Terrain type– Snow depths– Soil strength
Operations: packed snow road • Swimming Point – Fall 1971
Date Total Traffic
Frost depth Under-road (cm)
Frost depth Undisturbed (cm)
October 6 0 8 8
October 8 2 passes 17.5 12.5
October 16 2 passes 28 15
(Muskeg Research Institute 1972)
Operations: snow vs ice roads
• Norman Wells test road - 1973
1. Packed snow road
2. Ice-capped snow road
3. Pure ice road (no snow)
(Adam 1973)
Operations: snow vs ice roads
• Packed snow road• inadequate compaction → failed light vehicle tests
• Pure ice road • withstood rubber-tired, but not tracked traffic
• Ice-capped snow road• withstood rubber-tired and tracked traffic
Operations: snow vs ice-capped roads
• Inuvik snow road - 1974 – Top 25 cm re-packed – No changes in thaw depth or
surface elevation
• Hardness: Inuvik 1000 R Norman Wells 250 R
(Northern Engineering Services 1974, Younkin and Hettinger 1978)
Operations: Multiple Seasons
• Shingle Point -1971-72– Active layer– more severely
disturbed areas– terrain type
(Kerfoot 1972)
Environment: Terrain type
• Swimming Point Freeze-up 1971-72
– Wet lowland areas: frost penetration slower & sensitive to disturbance
• Mallik & Taglu Summer 1973
– Sedge wetlands less sensitive to disturbance than shrub uplands
(MRI 1972, 1973)
Environment: Snow depth & Soil strength
• Snow - protects vegetation and organic layer → Measure: snow depth snow density road hardness
• Soil strength - increases as ground freezes → Measure: ground hardness
ground temperature Freezing Degree Days (FDD)
Snow depth & Soil strength – Start-up Dates
Study location FDD Snow depth (cm)
Mallik & Taglu(MRI 1972) 20
Swimming Pt.(MRI 1972) 150
Review of operations in the Mackenzie Delta(Interim 1973)
20
Review of operations in northern Canada(Adam 1974, 1978)
306 10
Soil strength – Comparison of FDD in Inuvik and Tuktoyaktuk
1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007
Year
100
200
300
400
500
600
700
Fre
ezi
ng
deg
ree
da
ys t
o N
ove
mbe
r 15
th
TuktoyaktukInuvik
0
100
200
300
400
500
600
700
Snow depths – comparison between Inuvik and Tuktoyaktuk
Dat
e of
15
cm s
now
acc
umul
ation
Year (Environment Canada 2008)
10-Oct-08
21-Oct-08
1-Nov-08
12-Nov-08
23-Nov-08
4-Dec-08
15-Dec-08
26-Dec-08
6-Jan-09
17-Jan-09
2000 2001 2002 2003 2004 2005 2006 2007
Inuvik 15 cm
Tuktoyaktuk 15 cm
Snow depths – Tuktoyaktukcomparison between 15 & 20 cm
10-Oct-08
21-Oct-08
1-Nov-08
12-Nov-08
23-Nov-08
4-Dec-08
15-Dec-08
26-Dec-08
6-Jan-09
17-Jan-09
2000 2001 2002 2003 2004 2005 2006
Tuktoyaktuk 15 cm
Tuktoyaktuk 20 cm
Snow depth – Shut-down Dates
• Swimming Pt. & Parsons Lk. Winter Roads – 1973– Snow depth– air temperature < 0°C– thin snow cover, southern exposure
Snow depth – Shut-down Dates– Northern CanadaAccumulation of 10 thawing degree days (TDD)
– Mackenzie DeltaMean daily air temperature > 0°C for
3 consecutive days
Shut-down Dates – Inuvik & Tuktoyaktuk, 10 Thawing Degree Days
April-10-08
April-20-08
April-30-08
May-10-08
May-20-08
May-30-08
June-09-08
1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007
Tuktoyaktuk 10 TDD
Inuvik 10 TDD
Conclusions
• Research limitations
– Older studies, short-term, lack of baseline, lack of disturbance intensity, qualitative impact assessment
• Operational considerations– Packed snow road (Inuvik) and ice-capped snow road
(Norman Wells) supported vehicle traffic with minimal environmental disturbance
– Roads used over multiple seasons had more severe disturbances
Conclusions
• Environment
– Sedge wetlands more sensitive to disturbance during fall
– Sedge wetlands exhibited less disturbance than shrub uplands
– Snow depth and soil strength are critical factors in determining dates for tundra access
– Current permit conditions for tundra access dates are protective according to thresholds based on previous research
Conclusions
• Environmental variability
– Accumulation of FDD during fall is similar at Inuvik and Tuktoyaktuk
– Accumulation of 15 cm snow in Inuvik can occur up to 1 month earlier than in Tuktoyaktuk
– Accumulation of 10 TDD in Inuvik can occur up to 1 month earlier than in Tuktoyaktuk
Recommendations
• Any new guidelines should take into account environmental variability of the region
• New research should consider what environmental indicators to measure
• New research should evaluate the impact of new operating procedures, and validate past results
Thanks,
Questions?