Ground truthing streamflow duration classification

Principal Investigator: Dr. Ashley Coble, NCASI

Supported by: Western Trade Association Member Companies

Project Summary: Forested stream definitions are a primary determinant of the degree of protection surface waters receive during forest management by determining allocation of buffers and their widths. As state and federal regulators consider levels of protection to achieve water quality objectives, proposed changes are expected to focus on protections of the smallest forested streams (Kampf et al. 2021), which often do not require forested buffers. A key challenge in ensuring protections is determining streamflow regime (duration). Defining these streams, while challenging, is a current focus of research, development of remote sensing tools, and citizen science initiatives.

Federal researchers are actively developing tools to improve streamflow designations, but the majority of data-informing modeling efforts in the western U.S. are derived from federal land. Federal and privately managed forestland often differentiate by biophysical factors such as elevation and gradient, which are identified as important determinates of streamflow duration (Jaeger et al. 2018). Privately managed forests may become regulated on the results of these models, in which private land is underrepresented.

This project will support a field team to verify streamflow regime across private forested lands. Data will be collected following USGS protocols using high-resolution GPS devices and will work to inform USGS and USFS modeling efforts on streamflow duration during summer low flow.

Contact Dr. Ashley Coble at acoble@ncasi.org