ABSTRACT
Thompson River valley is a vital section of the strategic national transportation corridor that runs through southern British Columbia. Main rail lines of the Canadian Pacific Railway (CPR), completed in 1885, and the Canadian National Railway (CN), completed about 30 years later, are located in this corridor (Clague & Evans 2003). The study area is located between Ashcroft town and Spences Bridge (50° 10 to 50° 20 N and 121° 15 to 121° 20 W) just south of Ashcroft town. This area has a history of landsliding which has created problems for both CPR and CN. When the landslides were rapid, they blocked the river, disrupted rail traffic and caused fatalities. When they move slowly, the rails need repairing every few years. Some of the slides created short-lived upstream reservoirs. Figure 1 shows the locations and names of the landslides in Thompson River valley. Table 1 gives the areas and volumes of few of the landslides in this area.
