Principal Investigator: Daniel Jones, U.S. Geological Survey, Eastern Geographic Science Center

The Science Issue and Relevance
Effective watershed and stream management plans require a detailed understanding of the location and structure of erosional and depositional features along channel reaches. A comprehensive accounting of these features can be used to reduce costs and promote the effectiveness of targeted conservation and management efforts. While field surveys provide the best accounting of these features, they are often impractical due to high monetary costs and lengthy time commitments. With the increasing availability of high-resolution topographic data collection technologies such as light detection and ranging (lidar), there is a need to develop and evaluate processing techniques that extract important geomorphic features across a range of topographic and land use settings. As part of the USGS Best Management Practices Designed to Improve Developing Landscapes project (https://egsc.usgs.gov/bmp.html) researchers have been exploring new techniques for extracting high-resolution drainage networks and other geomorphic features from lidar data. This work has potential implications for stormwater and watershed management strategies that could have broad reaching importance. The methods and products from this work will help in the identification of new areas in need of conservation (e.g., new riparian areas, endemic habitats, etc.).

Methodology for Addressing the Issue
Comprehensive channel head and drainage network field surveys are coupled with timely lidar acquisitions to document the occurrence and location of channel heads in watersheds spanning a range of land uses. Lidar-derived channel networks are compared against field survey data to assess accuracy in predicting channel head occurrence and their locations. Terrestrial lidar-based morphometric surveys are used to evaluate channel head morphology and assess which characteristics are apparent or lost in the airborne lidar. Notes and locations of erosional and depositional features are used to assess the variables influencing channel and geomorphic feature detection methods.


Future Steps
Future developments will extend the work into new watersheds to gain further understanding of how the methods perform in a range of topographic and land use settings.

Key Words: Lidar, channel networks, geomorphic feature extraction, Best Management Practices, channel delineation


Contact Information:
Daniel Jones
204-620-7822
dkjones@usgs.gov