Impacts of Roads
What impacts does a road have on society? On the environment? What are the benefits and the consequences? In this section, you are given the opportunity to delve more deeply into these questions where there is no “clear-cut” answer.
What do we see?
"The
real voyage of discovery consists not in seeing new landscapes, but in having
new eyes." Marcel Proust
Often when we look at a landscape, our unique
perspective can act as a filter for how we interpret what we see. As you look
at the three photographs presented in the text box below, allow your initial
thoughts to surface about the image—these may be along the lines of where, why,
when or who built the road. Continue to look at the pictures. What other thoughts
surface?
Image 1: Image 2:
Image 3:
What these images might show…
1.In the first image, the high density of roads creates a patchy forest, leading to fragmented habitat. This can have a particularly large impact on animals such as bears who require large areas of habitat, and caribou who have summer and winter migration routes.
2.The second image illustrates a road crossing a stream. During construction, sediment can be released into streams, which can alter the water flow and cause water pollution. The use of culverts may also impede fish migration.
3. The third image shows a road being constructed in the winter. One can see large cleared areas on either side of the road. Buffers can be home to new plant species in the spring, some of which could be invasive and reduce the ability of native plants to grow in the areas, potentially impacting wildlife who rely on those plants.
These are just some of the potential impacts of roads.
View the maps for a “bigger
picture” of road development.
View the following Maps by selecting “Map” at the top of the page, under “Impacts”.
A map of roads in
A map of roads in FML01: View a road density map for Tembec’s FML- entitled “Infrastructure” (pdf).
Reflection:
What has been your experience of the environmental or social impacts of roads?
A Comprehensive List of the Impacts of
Roads
Research increasingly indicates that impacts of roads varies according to the type of road, how the road is used, the density of the road network and the tolerance of plant and animal species to impacts such as landscape patchiness or increased hunting access. While there is no definitive answer as to how roads impact the environment, it is becoming increasingly clear that the impact of roads often extends far beyond the edge of the road itself.
The following table provides a list of potential environmental and social impacts of roads. Not all impacts are negative, and some will impact certain areas more than others.
|
Environmental Impacts |
Category |
Impact |
|
Air quality |
·
Dust
during construction which can affect plant growth ·
Air
emissions from vehicle traffic may impact growth of organisms and quality of
habitat in region |
|
|
Water quality |
·
Water
runoff carrying sediments, salt and oil from road maintenance, and pollutants
from vehicles, makes its way into soil and waterways. ·
Bridges
and culverts can harm wetlands and fish habitat, block migration pathways and
pollute water. |
|
|
Soil |
·
Soil
compaction ·
Increased
erosion and sedimentation; altered natural streamflow
patterns |
|
|
Vegetation |
·
Invasive
species are able to enter new areas more easily, competing with native plant species ·
Logging
trucks sometimes transport root disease ·
Removal
of original vegetation cover ·
Barrier
to dispersal of organisms |
|
|
Wildlife |
·
Disruption
of wildlife home range ·
Increased
road-kill reduces wildlife populations ·
Increased
hunting access (including illegal hunting) also reduces wildlife populations ·
Traffic
noise may impact the ability of song birds to reproduce, thereby decreasing
population densities |
|
|
Landscape |
·
Habitat
is broken into smaller pieces which is harmful to animals that need large, uniterrupted landscapes (like bears) ·
Some
species may grow more easily along the edges of roads; some may be pest
species ·
Disruption
of hydrologic processes ·
Changes
in landscape may occur beyond the edge of the road |
|
|
|
Access |
·
Access
to mining, hunting, forest harvesting and off-road vehicles increases |
|
Social Impacts |
Tourism |
·
Loss
of tourism opportunities in remote, roadless areas ·
Increased
tourism and sport activities in previously inaccessible areas |
|
Noise pollution |
·
Noise
from traffic and construction |
The above table
was compiled using the following information sources:
Saunders, Sari.,
Spellerberg, Ian. (1998) Ecological effects of roads and traffic: a literature
review. Global Ecology and Biogeography Letters 7, 317-333.
Trombulak, Stephen C. and Frissell,
Christopher A. (2000) Review of Ecological Effects of Roads on Terrestrial and
Aquatic Communities. Conservation Biology. 14, 1
18-30.
More information can be found
at the following websites…
1. Wildlands League developed a webtour showing the impacts of unplanned development, and includes a section on road development.
“We have created a series of hypothetical illustrations that illustrate what happens when a series of individual development decisions are taken in a previously intact wild area…”
http://www.wildlandsleague.org/bigwild/conventionaldevelopment.html
On the same Wildlands League website, another list of the impacts of roads is provided. http://www.wildlandsleague.org/roadimpact.html
2.
CPAWS -
http://www.cpawsmb.org/take-action/parkwatch-bulletin-jan2004.html