Forest Road Deactivation Practices
in the Pacific Northwest
10 - Cross-Ditch (Pullback)	Description, Expectations

Description

Cross-ditches in pullback are used to restore hillslope drainage to historic (pre-construction), natural flow patterns. Cross-ditches are located at gully channels, natural depressions and swales which have evidence of stream flow and seepage above the road. The size, depth and shape of a crossditch depends on hillslope and gully contours, but it should always mimic natural ground profiles and contours. In this picture, note the recontoured slopes. If sediment transport is a concern, then more armour is needed at the bottom of the cross-ditch.

Expectations

1. Decompact, remove and outslope the road surface in the vicinity of the cross-ditch.
2. Remove all fill from gully. The order of pullback placement must be planned.
3. Re-establish watercourse to native ground if possible.
4. Reslope gully sidewalls to natural stable angles.
5. Place rock in base of re-established gully if natural gully channel is erodible. Key in the lowest row of rocks for toe support.
6. Never direct water onto unstable slopes/unprotected erodible soil. "Cross-ditches in Pullback" Practices aim to mimic natural hillslope contours and drainage paths wherever possible.

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Introduction  1   Water Management  2   Waterbars & Ditchblocks  3   Safety and Road Surface  4   Revegetation  5   Sediment Control  6   Erosion Protection  7   Dewatering Streams  8   Cross-Ditches (Road Intact)  9   Cross-Ditches in Pullback  10   Partial Sidecast Pullback  11   Full Sidecast Pullback  12

13  Blanket Drains   14  Trench Drains   15  French Drains   16  Fords   17  Cross-Ditching Practices   18  Cross-Ditching in Pullback   19  Partial Pullback Practices   20  Full Pullback Practices   21  Wood Culvert Removal   22  Metal Culvert Removal   23  Stream Diversion Dams   24  Pre-Work Checklist

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