December BMP Q&A

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

Q:   I am about to begin harvesting on a tract which shares a border with one of our National Forests and is also bordered by a major river; Are there any special BMPs that I should be aware of before I begin cutting? Specifically do I need to leave a buffer strip on the border with the National Forest or a wider SMZ on the major river?

A:   I recently received a phone call asking this very question from an interested individual. It is important to remember that the primary function of any BMP is to protect and minimize impacts to water quality from forestry operations. This question reveals that often times there can be confusion between what exactly are BMPs and what are policies/requirements that some companies, consulting foresters, and even landowners want met during operations.

For example, a timber company may require that an aesthetic buffer strip be left on any adjacent boundaries to the National Forestland. While this may be a requirement by the timber company, it is not related to the protection of water quality and thus it is not a BMP guideline or recommendation. It would certainly be prudent (especially if you wanted to continue your employment with this company) to leave the buffer strip, but during a BMP implementation evaluation, there would be no consideration given as to whether or not you followed company guidelines. The only consideration would be did the operators follow the guidelines set forth in the “Bluebook” and did the BMPs that were implemented effectively minimize and protect water quality on the site.

The second part of the question deals with the width of the SMZ on a major river. There is no special classification for rivers whether they be considered major or minor, they are all classified as perennial streams. There are however, several factors that need to be addressed before an answer about SMZ width can be determined. It is a known that the SMZ should meet the minimum width of 50 feet on each side of the river. There are two separate directives in the “Bluebook” that address the need to determine if the SMZ should be wider:

BMP Guidelines, Section 9.23, Pg. 28

"The width of an SMZ should be a site-specific determination made by foresters or other qualified professionals. Soil types, slope gradient, vegetative cover, volume of flow, and stream classification should be taken into consideration when designing each SMZ."

Recommended Specifications, Section 9.11, Pp. 58-59

"The width of the SMZ should be adjusted for slope, soils, and cover type and especially when protecting municipal water supplies"

Both of these directives indicate that a wider SMZ is certainly a possibility. Both of the directives also point to site conditions that should help you to determine if a wider SMZ is needed. According to the SMZ width chart on page 59 of the “Bluebook,” a 100 feet wide buffer is necessary if the river is a municipal water supply, i.e. water is being treated and used as the water supply for a community. I would suggest that some evaluation is needed of the soils and slope to fully answer this question. However based on the information that this is a “major river,” it probably has a large volume of flow. I would make a recommendation that the SMZ width be increased past the minimum width of 50 feet and I would further use the site’s soil and slope conditions to determine how much wider.

For more information regarding BMPs consult the Texas Forestry Best Management Practices book (a.k.a. the “Bluebook”), contact your local Texas Forest office, or you can contact me.

* This article was published in the December 2007 issue of the Texas Logger