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slope road surfaces laterally either outward or inward, depending 



on traffic needs and erosion hazards. Unfortunately, traffic can 



cause some rutting in the road surface that concentrates flow along 



the road in spite of the outsl oping or ins loping. ThuS;in many situations, 



additional cross-drainage measures are needed to interrupt this flow 



and divert it laterally before it has a chance to cause erosion problems. 



D. Slope Stabilization Measures 



Slope stabilization includes revegetation and other measures to control 

 surface erosion on road cut and fill slopes and on waste and borrow 

 areas. Usually the objective is to establish a dense vegetative cover 

 to reduce forces available for erosion and increase surface protection. 



1. Apply stabilization practices immediately following construction. 

 Some stabilization practices may be desirable during construction. 

 Use practices that provide rapid benefits. 



2. Site factors governing air and soil temperature, soil moisture, 

 and fertility are important influences on revegetation success. 

 Large variations in these factors can occur throughout the length 

 of a road, particularly in low precipitation zones or in areas 

 with prolonged dry seasons. Such differences are often magnified 



in mountainous areas. It is important to tailor revegetation measures 

 to the specific site factors. Consider elevation, aspect, rain 

 shadow effects, groundwater seepage, soil and bedrock properties, 

 etc. in evaluating site differences. Include vegetation in the 

 evaluation, both as an indicator of site potential and to serve as 

 a guide for species selection. 



