Monday, May 1, 2000

May BMP Q&A

By: Jake Donellan, BMP Forester (Ret.), Texas Forest Service

Q: A buddy of mine recently completed the BMP training course. He told me that I should not only put water control structures on haul roads but that I should also put them on skid trails. Is this really necessary, especially when I know that a site prep crew and planting crew will be on that site within a couple of months.

A: I am glad to hear that your buddy remembered that point from the BMP training course he attended. The answer to this question is, YES. Waterbars may be needed to stabilize skid trails but I wouldn’t necessarily suggest them on active haul roads.

On haul roads, rolling dips (Pages 45-46 in the Blue Book) may be a better alternative than waterbars. Rolling dips are basically extended or stretched-out water bars that are easier for trucks to drive over. On roads where there is a lot of traffic, rolling dips will definitely last longer than waterbars.

Skid trails typically don’t receive as much traffic as haul roads. Therefore, waterbars can be very effective if placed and constructed properly. Your initial thought may be that skid trails aren’t really that important. You may think that most skid trails will probably heal up before any erosion takes place. In some cases this may be correct. Often times, this is not the case.

Many times you expect a site prep crew to come in soon after a harvest. It seems senseless to put in waterbars on skid trails when a site prep crew might knock them down. It doesn’t always happen that way. For one reason or another that crew may be delayed for months or even a year. During that delay the site is exposed and a large amount of erosion and/or soil movement could occur.

About 90% of all sedimentation from a logging site comes from the road system. The road system is not limited to haul roads; it also includes skid trails. It may not be necessary to build waterbars on every skid trail. Your experience, based on topography and soil type, will tell you when it is necessary to stabilize skid trails.

Often times it may not be practical to build a waterbar on a skid trail. It can be extremely difficult, especially with all the stumps and roots in a skid trail. Placing slash in the skid trails may be a good alternative to building waterbars. These slash piles act similarly to a waterbar by redirecting and slowing the speed of the water moving downhill.

If you feel that a skid trail has the potential to wash out or erode, chances are it will. Therefore it is important then that you take the appropriate measures to stabilize that trail. An environmentalist considers a cup of dirt entering a stream from a logging site as a significant impact on water quality. While that is extreme, if we can keep a cup of dirt on that skid trail by placing waterbars and slash piles, then that is one less cup of dirt entering that stream on your logging site. That is also less ammunition environmentalists have to force you into government regulation.

Any questions or comments can be directed to me.

* This article was published in the May 2000 issue of the Texas Logger

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