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Forest Roads And Their Effect On Water

Quality Essay, Research Paper


Forest Roads And Their Effect On Water Quality


Roads are often necessary to perform certain tasks in the forests. When roads


are made, they often pose the problem of erosion, and damage to nearby


water sources. The two articles I read on this topic were both from the


August 1999 issue of the Journal of Forestry. Both discuss the different


techniques and methods for trying to limit the amount of silt that contaminates


roads due to disturbance.


The first article, ?What We Know- and don?t know- about Water Quality at


Stream Crossings,? discusses the different methods used to cross streams, and


which method causes the most long term, and short term damage to water


supplies. Forest road crossings have become a concern, because they are


places where disturbance, and water run off cause silt to get into streams and


water sources. The three main methods discussed in detail in this article for


crossing a stream are: fording, using culverts, and either a temporary or


permanent bridge.


The most impactive method, according to this article was the practice of river


fording. This method causes inordinate amounts of downstream silt because


every time a vehicle fords a crossing, some contaminates are added to the


water, in addition to the silt on the stream bottom that is disturbed and


washed downstream.


In terms of impact, putting culverts in a stream causes about the same initial


impact, as creating a ford, but subsequent impact is less, because cars are no


longer forced to drive through the water. Culverts can cause problems too,


because of the potential for them to plug up, causing washout, and silt


deposits.


The

third, and most preferable method, according to this article, is the


construction of bridges (either permanent, or temporary).


By doing this, virtually all contaminants remain free of stream water, because


the actual stream does not have to be disturbed.


The second article summarized, ?Forest Roads: Where Soil and Water Don?t


Mix? shared similar opinions on most points. This Article brought up


several additional and perhaps more idealistic points. According to this


article, most resource damage in an area is done in the first two years after a


road is constructed. During construction, this article points out that it is wise


to limit the number of stream crossings to a minimum.


When crossings are necessary, though, this article suggested the use of


sediment ponds, and not allowing water to build up it?s mass and momentum.


When momentum is built up, water will erode more of the earth, causing


more sediment build- up in streams.


Personally, I did not really realize that there was even an issue of too much


sediment in streams due to forest roads, and stream crossings. It was


amazing to learn of all the dangers to the environment caused by yet another


type of pollution. This problem might not cause the immediate and drasti


problems that other environmental issues might, but eventually, because of


our interactions with the forest and it?s waterways, we might alter the


ecosystems in ways that we can?t even fathom.


1. Egan, Andrew F. ?Forest Roads: Where Soil and Water Don?t Mix.?


Journal of Forestry. 97. August 1999. 18-21.


2. Taylor, Steven E., Et Al. ?What We Know- and Don?t Know- about Water


Quality at Stream Crossing.? Journal of Forestry.97. August 1999. 12-16.

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