Road systems on the nation’s public lands are vital links; providing access to perform management prescriptions, fire management, and recreation opportunities. Sediment movement downslope of forest road systems is a concern because these sediments have the potential to reach stream systems. Filter strips and stream side management zones (SMZs) are recommended and implemented to minimize sediment delivery to stream systems. However, the effectiveness of these practices in controlling sediment movement and minimizing sediment plume development has seldom been assessed. This study was undertaken to assess sediment travel distances downslope of forest roads and characterize the factors influencing these distances. A total of 235 forest road turn-outs (lead-off ditches) were randomly selected on National Forests in Alabama and Georgia. Visible sediment plume lengths were measured for each selected site. Additional parameters quantified include downslope gradient, road section length, road width, and road gradient. The objective of this paper is to report the findings of the study assessing sediment plume development from forest road turn-outs. This paper also examines how the study results relate to suggested BMPs for forest operations below forest road turn-outs in Alabama and Georgia.
Grace, Johnny M., III. 2004. NPS pollution related to forest management activities in southern states. Proceedins of 2004 ASAE / CSAE Annual International Meeting; Paper No. 04-5019. 1-4 August 2004; Ottawa, ON, Canada. American Society of Agricultural Engineers, St. Joseph, MI. 17 p.