Research

Erosion of Unpaved Forest Roads

High-traffic, near-stream (HTNS) unpaved forest roads associated with timber production are some of the largest sources of excess, human-caused fine sediment in nearby streams. This fine-grained sediment generated by and transported from HTNS forest roads can adversely affect water quality and aquatic resources in nearby watersheds.

The Road Prescription-Scale Effectiveness Monitoring Project (RPSEMP) aims to study the erosion of unpaved forest roads in western Washington and the best ways to mitigate such erosion. This project is funded by the Cooperative Monitoring, Evaluation, and Research (CMER) Committee within the Washington Department of Natural Resources (WADNR) Adaptive Management Program. 

The project design includes the collection of extensive field data in western Washington, as well as the development of a process-based model. RPSEMP is a collaborative effort among members of WADNR, Rayonier, the United States Forest Service (USFS), and the Watershed Dynamics Research Group at the University of Washington. The project consists of three main parts: the major experiment; the parameterization experiments; and the modeling. 

The major experiment is designed to measure annual sediment load and quantify how forest road best management practices (BMP) that are put in place affect that sediment load. Sediment and flow data are being collected at each of the 78 field sites (80-meter segments of road) installed in western Washington. At a few subsets of these sites, traffic and rainfall data are also being collected. The parameterization experiments are designed to help answer six critical questions posed in our study design that are not necessarily answerable by the major experiment alone. The modeling component of this project is designed to develop a process-based model of forest road erosion that incorporates the effects of traffic and BMP. The model is being developed using Landlab, a Python-based Earth surface processes modeling toolkit.

As a Ph.D. student at UW (September 2016 – June 2024), I was extensively involved in the development and implementation of multiple parameterization experiments, specifically those related to the hydraulics of roadside ditch lines and the micro-topographical changes of the road surface over time. As a postdoctoral scholar at UW (June 2024 – present), my main involvement is in the model development.