Geomorphological aspects of road construction in a cold environment, Finland

Traditionally, road alignments followed easy landscapes and suitable landfo rms. When traffic and the size and weight of vehicles increased and higher speeds were used, straighter roads were required; the easygoing relief coul d not always be used, and problems arose. Road contractors could save money in building and maintenance costs by considering the geomorphic facts. The examples from Finland document why road construction is very expensive in the conditions generated by severe winters. In Finland, more paved roads cr oss the Arctic Circle than in the whole of North America. This paper gives examples of geomorphic elements affecting road construction in a cold envir onment: eskers, drumlins, plains of late and postglacial glaciolacustrine a nd marine sediments, mires, steep rock cliffs, river channels and ice-dams, fluvial erosion, and palsas. Solutions to these problems include removal o f frost sensible materials and replacement by more favorable sediments. Roa d surfaces, kept snow-free in the wintertime, are subjected to deep freezin g. The maintenance of roads can be supported with some solutions that affec t snowdrift and icing problems, avoidance of geomorphic factors that cause problems, and by using natural processes to help people. Some examples of h ow road construction affects geomorphic processes and vice versa are provid ed. For example, bridges block moving river ice, and on special occasions, road banks cause icing. (C) 1999 Elsevier Science B.V. All rights reserved.