TEHCC Patch

A.T. Drainage

Last revised: March 08, 2007

DRAINAGE

Time + Energy + Money = Trails (A big investment!)
Water (the universal solvent) Dissolves, Destabilizes, and Erodes Soil
Water + Trails = Trail Problems

When do you know there is a Trail problem?   You must know the desired Trail experience, and you must have consensus Trail standards by which to judge the situation.  The standards may be based upon indicators such as those, below.

Problem Indicators for Water on Trails:

bulletBare Soil
bulletErosion: loose rocks, exposed roots, gullies
bulletWidening Tread
bulletMultiple Treadways
bulletWater Running Along the Trail
bulletClogged Drainage Structures (waterbars, grade dips, drainage ditches)
bulletTrampled Vegetation
bulletStanding Water
bulletMuddy or Boggy Areas

Solutions for Problems Caused by Water on Trails:

  1. Thoughtful Trail Design
    bulletmatch grades to soils and expected use
    bulletbuild in slight outslope and adequate water diversion/drainage
    bulletavoid problem areas, or build the Trail to handle them
  2. Locate the Source of the Water
  3. bulletraindrops - splash erosion
    bulletrunoff - during rain or snow melt
    bulletrunoff - from intercepted ground water
    bulletseeps
    bulletstreams
    bulletlow areas
  • Separate Water and the Trail Tread
  • bulletleaf litter on the tread to buffer/prevent splash erosion
    bulletdrainage structures to divert water
    bulletwaterbars
    bulletgrade dips
    bulletundrained flat areas
    bulletstep stones
    bulletbog bridges
    bulletdraining flat areas
    bulletdrainage ditches
    bulletculverts
    bulletturnpike
    bulletgeo-textile
  • Slow the Velocity of Water Along the Trail Tread
  • bulletsteps
    bulletcheck dams
  • Maintenance
  • Treadway Standards to Deal With Water on Trails:

    bulletTread width should be 12 to 24 inches
    bulletSoil erosion (rutting) should be less than 3 inches deep
    bulletSoil erosion (rutting) on relocated or rehabilitated sections should be less than 1 inch
    bulletExposed roots should be covered; root loops should be removed
    bulletThe trail should have one treadway for single file use
    bulletMuddy sections should not exceed five linear feet of constantly muddy soil
    bulletWater should run next to or across the tread, not down the tread
    bulletGraveled tread should be minimized
    bulletDrainage Dips should be functioning, clean and well maintained
    bulletWaterbars should be functioning, clean and well maintained
    bulletRock or log cribbing and retaining walls should be intact and serving their original purpose
    bulletCulverts should be functioning, clean, well maintained and safe
    bulletSteps should be sound, flat, well maintained and safe

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