Erosion control along transportation routes in northern climates

摘要

The widespread occurrence of permafrost in northern climates dictates the use of specialized measures to protect the terrain from adverse impacts associated with the construction of transportation facilities. Through the adoption of appropriate construction techniques and by providing proper drainage and erosion control facilities within the right-of-way, serious environmental degradation can be avoided. The most appropriate type of erosion control measure is selected according to local terrain and drainage conditions, including a Soil Erosion Code (SEC). Erosion control begins with the provision of effective drainage across the right-of-way. Typical erosion control measures include the use of permanent linings such as granular blankets, rock riprap and gabions and temporary linings, such as plastic sheets and fiberglass rovings. Ditch checks, rock aprons, energy dissipators and siltation basins may be used to minimize erosion of exposed soils along the route and attendant siltation of streams. Cut slopes may be protected with insulation in ice-rich, fine-grained soils to ensure stability and prevent slump material from reaching the drainage system. Ultimately, long-term erosion protection along transportation corridors is provided through appropriate revegetation techniques, periodic surveillance and regular maintenance of drainage and erosion control facilities.