The Chattahoochee River National Recreation Area (CRNRA) has challenges protecting the health of the river as a result of runoff from land development, wastewater overflow, and impacts from the regulated water discharges of Buford Dam. To help better manage the river, the National Park Service needed to continuously document the streambank and channel conditions on all 48 miles of the river associated with the CRNRA.
To accomplish this, Trutta Environmental Solutions was contracted to assess the habitat type (riffle, shoal, run, pool), condition of the left and right streambank, and water depth on 48 continuous miles of the Chattahoochee River. Additionally, a recreational use suitability model that included wading and boating types was developed, requiring the additional parameter of channel roughness to be classified. To accomplish this, a longitudinal HDSS survey was conducted to collect a broad suite of video, sonar and GPS data. A standard set of classification criteria was applied to the field data to determine streambank and channel conditions and to develop the suitability model for recreational use. A StreamView video for the entire stream, a database including GIS layers for the three parameters of depth, habitat type, and streambank condition, a recreational use suitability model, and a list of the 20 worst stream segments were provided. Additionally, the classification and development of GIS layers for the recreational use suitability model were included.
The High Definition Stream Survey (HDSS) approach was created to rapidly gather continuous, meter-resolution GIS data in a single pass for a broad range of stream corridor metrics by integrating GPS, video, depth, side scan sonar, and other sensors. Once the data are collected, the videos are combined into four simultaneous views of the river. Each second of video is linked to a specific GPS point which allows for the identification, selection, and prioritization of streambanks for restoration. The results can also be used to monitor restoration results, determine the extent and distribution of instream habitat, define the geomorphic condition for the stream, identify infrastructure impacts, and provide a powerful “virtual tour” experience.