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The Trail Companion
Summer 2000
Handbook for Forest and Ranch Roads
A guide for planning, designing,
constructing, reconstructing, maintaining and closing
wildland roads.
Prepared by William E. Weaver, Ph.D. and Danny K.
Hagans, Pacific Watershed Associates for the Mendocino
County Resource Conservation District, June 1994. $20.
(Available from the Mendocino County Resource Conservation
District, 405 Orchard Ave., Ukiah, CA 95482 (707)
468-9223.)
Reviewed by Geoffrey
Skinner
While a handbook on roads may seem out of place on the
trail building reference shelf, this guide is loaded with
useful information easily adapted to the world of trails.
Bern Smith, former Trail Center President and Crew Leader,
recommended this book to me and I recently ordered a copy
from the Mendocino RCD. The authors emphasize low-impact
construction, particularly as it applies to streams and
watersheds. Anyone who hikes, bikes or rides has probably
encountered poorly designed and constructed roads which
have eroded or collapsed into watercourses, whether in the
National Forests or in the old ranches which make up many
of our regional parks. Unfortunately, the poorly designed
trail will cause the same damage-trails can be regarded as
very small roads, with all same issues of drainage and
proper design. As anyone who has worked on trails knows,
water can be a great force for destruction, particularly in
heavy water years such 1997/1998. The better our
understanding of why roads (and trails) fail, the better we
can avoid making the same mistakes in future
construction.
Although much of the
language will be familiar to anyone who has built trails,
the many technical terms could make the handbook a
difficult read for the layperson. Fortunately, the authors
provide a fairly comprehensive glossary and numerous
illustrations.
- From the Introduction:
- If you work in a wildland area, own forest or ranch
land, or are concerned about our natural resources, this
book is for you. It contains guidelines for developing
and maintaining a single forest or ranch road or an
entire wildland road-access system. It describes how to
plan and design a stable road or road network in
mountainous lands or gentle valley bottoms, and avoid
many of the common pitfalls and environmental/pollution
problems for which rural and forest roads are noted.
Nearly everything discussed in this manual is aimed at
producing efficient, low-cost, low-impact roads that have
a minimal effect on the streams of a watershed.
- From Chapter VI: Construction, Compacted
cut-and-fill and benching construction:
- Multi-benching construction employs a technique
called "bottom-up compaction" which adds stability to
fill material placed along the outside of the road prism.
Multi-benching is not often used, but it is a good way to
develop a stable footing with a minimum of sidecasting
[dumping excess material over the side of the
bench].
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| Fig. 55. Multi-bench road
construction. |
First a bench is cut at the proposed base of the fill,
about 30 feet below the elevation of the proposed road
grade (its exact location depends on the slope of the
hillside and the width of the final road). It may be
necessary to excavate and endhaul material from this first
cut so it is not sidecast downslope. Next, the operator
moves slightly upslope to create another bench, casting the
spoil material onto the first bench downslope where it is
then compacted. After the second bench is completed, the
process is repeated upslope to the final road elevation.
The result is a fill that is keyed into the hillslope on
multiple, small benches, with little sidecast.
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