Wednesday, September 1, 2010

September BMP Q&A

By: Chris Duncan, BMP Forester (Ret.), Texas Forest Service

Q:   I ‘m getting ready to move onto a fairly large tract for a timber harvest.  This particular tract doesn’t have much in the way of an established road system, so I will be constructing most of the roads for the harvest.  The landowner wants me to make part of the road system a permanent road which he will be able to use for access to his tract in the future.  I anticipate that I will need to have at least 1 and maybe 2 material borrow sites to complete this permanent road as the landowner has requested.  What I would like to know if there any guidelines for road material sites that pertain to best management practices?

A:   This is a very good question.  We have written several articles in the past about road BMPs, but have not mentioned a whole lot about what should be done if there is a need to “borrow” materials from the site.  Deposits of surfacing, fill, and site stabilization materials located on the tract are an extremely important resource for forest management activities.  Excavation of these deposits represents a potential for nonpoint source pollution.  Proper planning, layout, maintenance, and reclamation are critical to ensure maximum utilization of materials while minimizing soil movement and impacts to water quality.

Carefully assess the tracts natural drainage patterns, soil types, slopes, and any adjacent streamside management zones (SMZ) to determine the best location, size, and shape of the needed material site.  Deposits covering large areas should be divided and worked in stages, maintaining a minimum size working area and accomplishing partial or complete reclamation of the disturbed area before moving on.  Avoid leaving large areas disturbed for extended periods, active or not.  Road material sites should not be located within an SMZ.  They should be located a minimum of 50 feet from the SMZ edge, but if they must be closer than 50 feet make sure to plan for control measures that will protect water quality.

While material sites are active; use settling basins, waterbars and/or terraces to slow runoff and disperse surface flow.  When extended periods of inactivity are expected, use temporary erosion control measures such as silt fences or straw bales to control surface runoff.  When possible, do site work during dry weather to eliminate excessive runoff and accelerated erosion of freshly disturbed areas.

Upon completion of pit operations and depletion of the deposit; redeposit and shape the overburden in a uniform layer over the pit area.  Make sure the pit has adequate drainage to prevent soil movement and stream sedimentation.  Finally, reclaim the site to aid the future use of the area and implement control measures to minimize surface runoff for each case.  Consider the area's slope, soil erosiveness, and capability to naturally revegetate and then fertilize and reseed all disturbed areas as needed.

For more information on forest road material site BMPs and other BMPs visit the Texas Forest Service webpage at http://texasforestservice.tamu.edu/water, contact me at (903) 297-3910.

* This article was published in the September 2010 issue of the Texas Logger