Forest Road Engineering Guidebook - Ministry of Forests

Forest Road Engineering Guidebook
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Refer to the Ministry of Forests package of road layout and design forms that
incorporate the above statutory content requirements. This information can
be found at an appropriate Ministry of Forests website.
Additional guidelines for preparing and implementing measures to maintain
slope stability are available in several Forest Regions.
Criteria for measures to maintain slope stability
If a proposed road will cross areas with a moderate or high likelihood of
landslides as determined by a TSFA, the person required to prepare a road
layout and design must ensure that it includes measures to maintain slope
stability that satisfy either Criterion 1 (hazard-based) OR Criterion 2
(risk-based). These criteria are explained below, and are consistent with the
requirements of Section 6 (1)(n)(i) and (ii) of the Forest Road Regulation.
Criterion 1
Code Requirement: In this criterion, the selected measure is the least
likely measure to result in a landslide, and a
qualified registered professional provides a statement
to this effect. (See Section 6 (1)(n)(i) of the Forest
Road Regulation.)
Criterion 1 is considered to be hazard-based (hazard being the likelihood of
landslide occurrence). It requires consideration of a limited number of road
construction techniques that are likely to result in the lowest likelihood of
landslide occurrence. Meeting this criterion would be justified in areas where
the likelihood of landslide occurrence is high, and where any measure other
than the “least likely measure to result in a landslide” would be unacceptable
to a district manager.
A measure that would satisfy the above criterion is any prescription or recommendation
for a road construction technique that will result in at least a
low likelihood of a landslide occurring. A qualified registered professional
must provide a statement to this effect to accompany the prescriptions or recommendations.
No other road construction techniques other than the ones
that provide for at least a low likelihood of landslide occurrence should be
considered. There are usually only a few methods of road construction that
fit this criterion, and most involve higher road costs. Obviously, the selected
measure should be considered in the context of conventional practices for
forest roads.
Examples of least likely measures to result in a landslide include any road
construction technique that has a low or very low likelihood of landslide
occurrence, such as: