The 869 km pipeline starts in Norman Wells, NWT and heads south to Zama, northern Alberta.

The 869 km pipeline starts in Norman Wells, NWT and heads south to Zama, northern Alberta.

The Norman Wells Pipeline, in operation since 1985, is the first completely buried oil pipeline in permafrost terrain in Canada. The pipeline was viewed in many ways as a pilot project from which lessons could be learnt for future pipelines in the Mackenzie Valley/Delta or elsewhere in permafrost environments. The pipeline has reached half of its originally anticipated life, and renewed exploration for hydrocarbons in the central Mackenzie may lead to an eventual extension of its lifespan. The 869 km pipeline stretches from Norman Wells, NWT to Zama, northwestern Alberta. Since start-up the Terrain Sciences Division has been involved in a Permafrost and Terrain Research and Monitoring Program along the pipeline route. The research program which arose from the Environmental Agreement between DIAND and Enbridge (the pipeline owner and operator, formely Interprovincial Pipe Line (NW) Ltd.) has involved many partners over the years, including NRC, DIAND, Ag-Can and Enbridge.

Many unique design features and mitigative measures were adopted to minimize disturbance to the thaw sensitive permafrost terrain and to ensure pipe integrity for the Norman Wells line. The small diameter pipeline operates as an ambient temperature line; oil is chilled at the surface and the average annual temperature of the oil entering the line is near -1°C. Of particular concern in the design was the potential for differential thaw settlement or frost heave across transitions from frozen to unfrozen terrain, and the stability of thawing permafrost slopes.

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Slope construction along the Norman Wells pipeline in winter 1984. Permafrost slopes that were thaw sensitive (i.e. unstable if thawed rapidly) were insulated with a layer of wood chips to prevent thaw. Special design and construction measures are required for permafrost environments. Photo shows wood chip layer being put in place.	Arctic ditcher used along the Norman Wells pipeline in winter 1984.
A series of instrumented sites were established as part of the government's research program. This cross-section, from a site located on a peat plateau south of Fort Simpson, shows the increase in thaw depth, and the associated ground surface settlement and pipe settlement that has occurred 12 years following construction.	Thaw depth and thaw settlement measurements from a study site in ice-rich silty clays at Norman Wells.
Seasonal and cumulative pipe movements are being monitored at a study site close to Norman Wells to determine pipe response to a seasonal oil chilling cycle introduced in 1993. Labels refer to distance along the 100m section of pipe under study.	Oblique view of insulated wood chip slope at kilometrepost 182 along the Norman Wells pipeline, May 1995. The area was swept by forest fire in 1994 triggering many landslides (active layer detachment type) along the creek valley, a few of which were adjacent to the pipeline right-of-way and necessitated some remedial work.
Upheaval of buried pipe, Norman Wells pipeline (Sept. 1997). The exposed pipe has since been covered by a berm.

The stability of ice-rich permafrost terrain and slopes along northern pipeline corridors, including sensitivity to climate change and forest fires, is part of GSC's pipeline research. Thaw sensitive slopes along the route were insulated with a layer of wood chips and the performance of these slopes has been a major focus of geotechnical monitoring programs. A few additional study sites examine the impact and recovery of terrain following a burn.

Most study sites have temperature cables in the "natural" terrain adjacent to the pipeline right-of-way. Long-term monitoring of these cables also provides data for permafrost and climate change impacts research.

GSC took on a pipeline safety research program, formely managed by the National Energy Board. Its goal is to develop new design standards for pipelines, both on land and offshore, to meet failure conditions caused by natural hazards. The program is improving methods for predicting the impact of upheaval buckling, ice scour, moving slopes, thawing and freezing soils on a pipeline, its coatings and well bores. The results provide a basis for establishing regulations and they help industry make desicions regarding safe and cost-effective pipeline design and maintenance strategies. The program encompasses several collaborative projects, with a broad base of industry, government and academic partners. Most projects are strongly supported by Canadian and international industry, leveraging Panel of Energy Research and Development (PERD) funds by a factor of ten.