Evaluating Winter Tundra Access Methods: Research Conducted in the Mackenzie Delta

1. Evaluating Winter Tundra Access Methods: Research Conducted in the Mackenzie Delta Julian Kanigan INAC Overland Winter Access Workshop, Inuvik, April 23-24, 2008

2. Outline • Operational considerations • Snow vs ice roads • Multiple seasons • Environmental considerations • Terrain type • Snow depths • Soil strength

3. Operations: packed snow road • Swimming Point – Fall 1971 (Muskeg Research Institute 1972)

4. Operations: snow vs ice roads • Norman Wells test road - 1973 Packed snow road Ice-capped snow road Pure ice road (no snow) (Adam 1973)

5. 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

6. 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)

7. Operations: Multiple Seasons • Shingle Point -1971-72 • Active layer • more severely disturbed areas • terrain type • (Kerfoot 1972)

8. 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)

9. 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)

10. Snow depth & Soil strength – Start-up Dates

11. Soil strength – Comparison of FDD in Inuvik and Tuktoyaktuk

12. Snow depths – comparison between Inuvik and Tuktoyaktuk Date of 15 cm snow accumulation Year (Environment Canada 2008)

13. Snow depths – Tuktoyaktukcomparison between 15 & 20 cm

14. Snow depth – Shut-down Dates • Swimming Pt. & Parsons Lk. Winter Roads – 1973 • Snow depth • air temperature < 0°C • thin snow cover, southern exposure

15. Snow depth – Shut-down Dates • Northern Canada Accumulation of 10 thawing degree days (TDD) • Mackenzie Delta Mean daily air temperature > 0°C for 3 consecutive days

16. Shut-down Dates – Inuvik & Tuktoyaktuk, 10 Thawing Degree Days

17. 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

18. 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

19. 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

20. 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

21. Thanks, Questions?