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

3. Operations: packed snow road Swimming Point – Fall 1971 DateTotal Traffic Frost depth Under-road (cm) Frost depth Undisturbed (cm) October 6 088 October 8 2 passes17.512.5 October 16 2 passes2815 (Muskeg Research Institute 1972)

4. 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)

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 Study locationFDDSnow 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) 30610

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 – Tuktoyaktuk comparison 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?