Drainage Ditches

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Drainage Ditches

• Photo Montage
• Douglas Daley
• FEG 437

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Forest Road Reclamation?
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Erosion Controlled
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Camp 3 logging road.  Faults uncovered sediment
on sides of road, no rock, no waterbars
Campaign to Restore Jackson State Redwood Forest
visited the "Camp 3" Timber Harvest Plan (THP)
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Camp 3 logging road.  Faults large sediment pile
in drainage path from road
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Camp 3 logging road.  Faults inslope drainage
ditch without waterbar, no rock.
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The angle of a back slope, shaped during
construction, is determined by the natural angle
of repose for the soil type. (Redrawn and adapted
from Hartung and Kress 1977, p. 11)
http//www.na.fs.fed.us/spfo/pubs/stewardship/acce
ssroads/construction.htm
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• Effective road drainage is vital to road safety.
• When road drainage systems do not function well,
  problems occur, for example
• too much water ponding on the surface,
  encroaching into driving lanes and endangering
  traffic safety
• cold weather icing problems
• erosion of drainage ditches
• frost heaving of pavement slabs
• risk of structural damage or failure of bridge
  decks
• damage to the aquatic environment from
  contaminants washing off the road and
• high costs of maintenance.
• Designing a good road drainage system depends on
  understanding the hydraulic operation of the
  system as a whole, including the role played by
  paved surfaces, gutters, median drains and
  various types of drainage inlets.
• Over-designed elements can accelerate runoff,
  washing contaminants from the road surface and
  contributing to high and fast flows in drainage
  ditches susceptible to erosion

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Lacking a Context Sensitive Approach

• Common, but lacking aesthetic

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Imperfections of a Concrete Lined Ditch
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Vectors and Trash
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Maintenance

• Ditches need to be cleaned out to maintain
  capacity

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Channel Protection
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Sedimentation
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