Research and development activities along the ITH corridor build on the rich geotechnical legacy that has been developed throughout the planning and construction of the project.
The Department of Infrastructure (INF) has undertaken and supported these projects with the purpose of:
- Assessing performance of the highway
- Providing advance alerts to potential problems
- Building expertise for future application.
Support for R&D activities is received from a variety of sources. To date, contributions from Transport Canada’s Northern Transportation Adaptation Initiative total $1,117,200. Many academics and numerous research institutions, both territorial and national, are also involved with this work. Regulatory bodies are interested in the findings of this research and, as such, have been supportive of the changes, additional requests, and permitting needed for this work.
R&D is carried out in a number of ways, from long term monitoring projects to test sections in the embankment or one time measurements. Some of the work helps us understand how the surrounding environment behaves (e.g. permafrost, hydrology), which provides context for other research and for the development of strategies to manage risk and mitigate concerns.
Climate change is having significant effects on northern environments and infrastructure. Moreover, the related increase in unanticipated climatic events (such as unseasonable temperatures or more precipitation) impacts the design, construction, and maintenance of infrastructure. R&D is critical to our ability to respond to these challenges. The ongoing monitoring, data collection and data analysis of the projects along the ITH corridor will provide valuable information towards developing resilient and sustainable northern transportation infrastructure in the presence of accelerating climate change.
Following are short descriptions of the research and development projects underway along the ITH corridor. Some of these projects have been undertaken by the INF, others are conducted in partnership, and some are carried out independent of the highway construction but serve to provide context which informs road performance, maintenance, and mitigation.
Geotextile reinforced deep fill test section
LOCATION: Kilometre 82
CONTACT: University of Manitoba
TIMELINE: Installed April 2015, extended monitoring to April 2019
FUNDING: Transport Canada
This project consists of two sections along the ITH which were constructed with the goal of monitoring the structural stability of deep fill highway embankments. One deep fill section was constructed using the methodology and materials which are standard along the ITH – this section provides a baseline. A second deep fill section was constructed using additional geotextile reinforcement. Both sections have been instrumented to allow for comparison and assessment of embankment performance. This information will subsequently inform solutions to address issues of excessive movement and instability.
Monitoring is projected to continue until April 2019, at which point the test sites will have 4 years of seasonal data, including at least 2 years of data collected during the operation of the highway and under varying climatic conditions. This data will allow for better understanding and evaluation of the performance of highway embankments in the Arctic, in particular:
• The effectiveness of wicking geosynthetic reinforcements to improve the structural stability of high embankment fills. The study will help develop the first design and construction methods for this new technology under Arctic conditions.
• The operating mechanisms of embankment lateral spreading. Identifying the roles of these mechanisms to embankment spreading will help develop mitigation measures to lateral movements of highway embankments in Arctic regions.
Challenges have been encountered with battery performance and reliability at the monitoring station. As such, researchers are currently looking at the potential for alternate power sources, including solar panels.
Alternative drainage structures test section
LOCATION: Kilometre 22.5
CONTACT: Terratech Consulting Ltd.
TIMELINE: January – February 2016
FUNDING: Transport Canada – Northern Transportation Adaptation Initiative
This project consists of three different structures installed along one section of the ITH, in order to test the applicability of innovative drainage designs. The ultimate goal of these tests is to determine if alternative drainage designs can reduce the potential disruption of the thermal regime at stream crossing sites and manage the impact of this disruption on the highway.
One crossing, 15a, was constructed using the methodology typical to the highway’s water crossings. At the second crossing, 15b, Megaflow HDPE culverts© were installed. The third crossing, 15c, utilizes a typical metal culvert but with adjusted installation, including sub-excavation to permafrost and backfill with a granular foundation. The 15c structure is set below the streambed and filled with granular material to simulate creek bottom. Both 15b and 15c used geotextile reinforced soil (GRS) backfill.
Thermistors installed prior to construction
LOCATION: Various locations from kilometre 0 – 120
CONTACT: Binay Yadav
TIMELINE: Installed April 2013
A number of thermistors are installed along the ITH corridor. Some of these were installed prior to construction in order to confirm assumptions made by the project engineers regarding ground temperature. “The collected ground temperature data was reviewed by the bridge structure foundation design lead and the geometric embankment design lead to confirm that the engineering and ground temperature assumptions used in the 100% Design Submission (September 4, 2013) were appropriate and valid based on the fall ground temperature data.” (Kiggiak-EBA memo dated November 2013).
Readings are taken in April and October, anticipated to reflect the warmest and coldest ranges for the active layer and near-surface permafrost. These ground temperature cables must be manually read, requiring a technician to visit the site with a switch box and multi-meter. Issues have been encountered with damage from wildlife, construction, or other interference.
Long-term monitoring of the thermistors is needed and is currently projected to continue until April 2019. At that point, these thermistor sites will have collected 6 years of seasonal data, including at least 2 years of collecting data during the operation of the highway and under varying climatic conditions. The data will provide a better understanding of the performance of highway embankments in the Arctic. They will allow evaluation of the relationship between infrastructure and ground temperature over time. This information will be used to inform future infrastructure projects in similar conditions of permafrost. Installation of data loggers which collect higher frequency ground temperature measurements is being considered to enhance this unique data collection network.
Bridge piling monitoring of adfreeze piles
LOCATION: At the 8 bridge locations
CONTACT: Ed Grozic
TIMELINE: Three bridges in Winter 2014, one bridge in Winter 2015 and four bridges in Winter 2016
Bridges along the ITH were designed using adfreeze piles. Stability of these piles is dependent on continuously frozen permafrost; therefore, thermistors are installed with the piles to monitor ground temperature.
Readings are used during construction to determine when the adfreeze bond between the pile and surrounding ground has been achieved. After construction, readings are used to monitor the bridge performance. Data also contributes to the overall ground temperature profile of the ITH.
Additional thermistors to be installed along ROW
LOCATION: Various locations from kilometre 0 – 120
TIMELINE: To be installed Winter 2017
FUNDING: DOT, Transport Canada – Northern Transportation Adaptation Initiative
Additional locations along the ITH right-of-way have been identified for installation of thermistors. Fifteen new sites are located along the 55 kilometres of embankment constructed in 2016 and 2017. They will provide ground temperature information which will be used to monitor temperature fluctuations in the road bed and embankment and to evaluate whether the active layer remains restricted within the embankment in areas of different thickness and terrain type. The highway design characterized four different categories of terrain according to risk; temperature data is one factor in verifying or corroborating the design assumptions.
Sentinel permafrost monitoring
LOCATION: Off the ROW, three clusters: southern (km12-14), central (km 41-43) and central north (km 79-81)
CONTACT: NTGS (Steve Kokelj)
TIMELINE: To be installed Winter 2017, with ongoing monitoring to follow
FUNDING: DOT and Transport Canada – Northern Transportation Adaptation Initiative (installation), NTGS and GSC (ongoing monitoring)
The objective of the sentinel permafrost monitoring project is to provide baseline information from different environments encountered along the ITH and to provide the foundation for a network of environmental and infrastructure related research across this region.
Proposed sites are situated in three clusters in the southern (km12-14), central (km 41-43), and central north (km 79-81) and are typically located 160-250 metres from the ROW to avoid potential roadside effects. Each cluster of sites will consist of monitoring in three main terrain types which include polygonal peatlands, fine-grained tills, and riparian areas. Long-term monitoring of the sites and data management will be through partnership between DOT, NTGS and GSC. Complementary data collection at these locations, including vegetation, snow and active layer monitoring will be organized by collaboration between these research partners. Training opportunities will be explored with Aurora College and the Natural Resources Technology Program.
Terrain, permafrost, and ecological recovery in northern borrow pits
LOCATION: PW10, 312, 174
CONTACT: NTGS (Steve Kokelj)
TIMELINE: 2017 – 2020
FUNDING: DOT, NTGS
Granular resource extraction is necessary for construction and maintenance of transportation, community and development infrastructure. All stakeholders wish to minimize environmental impacts; however borrow pits constructed in ice-rich permafrost terrain remain a developer, regulatory and community concern due to a combination of factors including terrain stability, water quality, ecological footprint and public safety.
Knowledge of the terrain and ecological conditions of historical developments is fundamental to evaluating site recovery. Monitoring the terrain and ecological conditions of a development can inform mitigation options, reduce uncertainty, or refine development practices. The large, rapidly developed borrow pits associated with the ITH provide an unprecedented opportunity to study the impacts of disturbance to ice-rich terrain and the physical and ecological process of stabilization. This project will implement field studies including installation and monitoring of ground temperatures, and a combination of ground-based and UAV survey techniques to generate information on the permafrost, terrain and ecological conditions at recent and historical borrow pits, utilize remote sensing methods to assess their footprint and change over time, and work with stakeholders to document “lessons learned”.
This project will promote dialogue between scientists, regulators, proponents, and communities contributing to improving environmental monitoring and management in the NWT.
CO2 flux monitoring and equipment testing
LOCATION: Source PW-10 and kilometre 22.5
CONTACT: Aurora Research Institute
TIMELINE: August 2016 – temporary installation
FUNDING: Independently funded, DOT provided in-kind support to access sites
Arctic tundra soils store more carbon than other terrain. Thawing will activate more soil CO2 production, whereby climate change produces a positive feedback loop. Given this context and the importance of permafrost to infrastructure stability, researchers are asking if CO2 Flux measurements at industrial sites could provide information about sub surface activity.
An August 2016 temporary installation looked at testing EodFD units. These portable, low power, inexpensive units have the potential to overcome many of the limitations of existing equipment; however, they require cold weather testing.
Three test units were deployed to kilometre 22.5 and run for 10 days, taking samples every 10 minutes. Units were placed in different conditions within the same area: at the edge of the road embankment, in disturbed but vegetated soil, and in natural, undisturbed vegetation. There were some issues powering the devices with a lack of sunlight and low temperatures, resulting in gaps in the readings.
Three additional test units were deployed to Source PW10. As with the other site, these were run for 10 days, taking samples every 10 minutes. The units were placed near the headwall of a permafrost slump: in shrubs, on the vegetated edge of the gravel pit, and in a scraped but unexcavated area. One device failed for unknown reasons and the two other devices performed similarly to those at the first location – losing power at times.
The data collected during this short trial suggested the following conclusions:
• CO2 soil flux in the Arctic is correlated with ambient temperature but lags several hours behind.
• Soil disturbances including vegetation removal and traffic over vegetation tend to lower CO2 soil flux long after activity has ceased.
• More than one soil process may be contributing to CO2 soil flux.
• Roadway embankment showed higher CO2 soil flux and was uncoupled from the adjacent undisturbed Tundra flux.
• CO2 soil flux beside an active permafrost slump was higher than at another study site but needs further study to understand how these two things may be related.
• Plant size was correlated with higher CO2 soil flux.
• CO2 soil flux may provide a simple, quick way to monitor and identify subsurface issues related to industrial activity such as road works.
LOCATION: Kilometre 82, Borrow Pits 174 and PW-10, as well as along the Dempster
CONTACT: NWT Centre for GeomaticS & Canada Centre for Remote Sensing
TIMELINE: July 31 to August 12, 2016
FUNDING: CIMP funding pending 2017-2020 60k per year
In August 2016, collaborative fieldwork between the NWT Centre for Geomatics, NWT Geological Survey, and Canada Centre for Remote Sensing tested the use of unmanned aircraft (UAS, UAV, or drones) surveys to describe permafrost thaw, landscape change and transportation infrastructure along the Dempster and Inuvik Tuktoyaktuk Highway Corridors. Preliminary results, based solely on field assessments and interpretation of the high resolution digital elevation models (DEM) derived from the photographs obtained during the surveys, indicate good data capture and effective modeling and visualization of thermokarst features, road embankments and borrow pits.
Surveys of this nature have the potential to inform planning or mitigation measures as the derivation of a fine-scaled DEM affords the inexpensive and rapid collection of data on site conditions, providing project proponents, regulators, and scientists with valuable insights on site topography, drainage, surface changes and the processes that may be modifying terrain surfaces. Furthermore, differencing successive surveys offers good potential to monitor the evolution of thawing landscapes, borrow pits and transportation infrastructure.
LOCATION: Throughout the right of way; initial test section near kilometre 1
CONTACT: DOT (Dean Ahmet)
TIMELINE: 2016 – 2017
This project will investigate various methods of seeding and re-vegetating disturbed soils and newly constructed embankment slopes to determine effectiveness in stabilization and erosion prevention. A number of factors have been considered in choosing the seeds for these applications. A small test section was attempted in 2016 and 4 samples of mulch/seed mixture are on site in preparation for further test sections in 2017.
Compilation of geotechnical data and open file report
CONTACT: NTGS, Wilfred Laurier University Department of Geography
TIMELINE: January 2017 – January 2018
This project will involve organizing, archiving, and publishing ITH geotechnical data in the NTGS open report, digital format. A student will compile metadata for all ITH boreholes following the NTGS Permafrost Database protocol, assembling all raw data in digital format and preparing an open report for review and publication. This initiative will ensure that the geotechnical legacy of the ITH planning and design will be publically available and easily accessible for future maintenance and mitigation planning, and terrain and climate change research in this region.
Winter hydrology of small streams and culvert icings
LOCATION: Various locations, TBD
CONTACT: Wilfred Laurier University (Tim Ensom)
TIMELINE: 2017 – 2019
FUNDING: DOT, applications submitted for grant funding
In permafrost environments, climate warming is extending the period of active layer freeze-back in autumn and early winter, increasing the potential for winter water flow. Recent monitoring of the ITH has revealed icings and other evidence of mid-winter flow in streams that were previously considered to be hydrologically inactive in winter. Interactions between subsurface flow, icings, and highway infrastructure are poorly understood and cannot be well predicted. The impact of such changes on natural hydrology is also poorly understood.
This research project is intended to provide northern communities and infrastructure planners with an improved understanding of the thermal regime of riparian systems in a warming climate, and to advance our predictive capacity with respect to the occurrence of icings. Research questions include:
a) What are the relations between icing formation and riparian thermal regime, spatial and temporal changes in snow cover, other meteorological events, subsurface hydrological conductivity, groundwater movement, proximity to highways, and other physical watershed parameters?
b) Are existing models of riparian thermal regime and river icings applicable to the study region, and can they be applied to predict icing occurrence?
c) What proportion of annual streamflow occurs during winter?
These questions will be addressed through reconnaissance of streams along the ITH and the monitoring of ground and water temperature, water depth in source water bodies, riparian soil moisture, and other parameters. Long-term research on the hydrology and permafrost of the study region by scientists at the Northwest Territories Geological Survey and Wilfrid Laurier University, in collaboration with others, provides context and direction for new investigations. This research program is a collaboration between the Northwest Territories Department of Transportation, Northwest Territories Geological Survey, and Wilfrid Laurier University.