Soil erosion reduces the aesthetic quality of trails, affects the longevity of trails, increases maintenance costs, degrades plant and animal habitat, and may affect public safety. Effects of erosion include:

• loss of surface soil through sheet and/or gully erosion,
• root exposure resulting in physiological stress to plants and shrubs and, in the case of trees, susceptibility to windfall,
• stream sedimentation, resulting in damage to spawning beds, increased turbidity and adverse effects on flow regime and stream flora and fauna,
• contamination of water supplies,
• failing slopes through slides and slumping.

• Locate trails in areas least sensitive to erosion. If this is not possible, use construction techniques that minimize erosion. Consider the use of bridges or trail surfacing.
  
  
• Use drainage controls on slopes. When surface runoff is low, direct it across the trail surface. When surface runoff is high, use a crowned tread with a ditch on the uphill side to lead water to grade dips, culverts or waterbars.
  
  
• Avoid steep sections susceptible to water erosion.
  
  
• Orient trails across slopes on the diagonal, or use switchbacks to climb steep slopes.
• Incorporate natural grade dips into the trail surface so that drainage is diverted at frequent intervals.
  
  
• Use steps or ladders on steep slopes, making sure drainage water is diverted from the top of steps.
  
  
• Slope the cross-section of the trail tread at approximately 2%, or 4 cm per 1 m of tread width to direct surface water off the trail.
  
  
• Use waterbars to direct water off the trail when using a cross slope on the trail tread and grade dips are not adequate to control runoff. Alternatively, construct water-bars out of stones 100 cm or greater in diameter. Place them across the trail in the same position as the log waterbar.