USING CONSUMER CAMERAS AND TERRESTRIAL PHOTOGRAMMETRY TO EVALUATE EFFECTS OF ANTHROPOGENIC STREAM MODIFICATION: UNCOMPAHGRE RIVER, COLORADO, USA

The quality of consumer cameras has increased dramatically in the last few years, making the art and science of photography a realistic option for low-budget operations. In addition, the flexibility of software packages has evolved outside of traditional aerial photogrammetry making terrestrial photogrammetry an accurate and affordable method of analysis. Within geomorphology, this allows high-resolution data to be collected more frequently on the ground under certain terrains. Photos were collected at various sites at various scales using wildlife monitoring time-lapse capsules as well as a consumer grade DSLR.

This study was designed to monitor areas of deposition and erosion within the stream channel to quantify sediment movement and determine areas of local erosion and deposition within a natural stream environment and a human-modified stream environment. The Uncompahgre River on the northern side of Ouray, CO has been modified into a recreation area with artificial meanders by confining a braided stream using riprap to prevent channel erosion. Sediment is dredged annually from point bars within the modified area and is removed from the river system. A variety of geometrical measurements indicate that the non-modified downstream portion is characteristic of a glacial stream, while the human-modified portion is characteristic of a meandering stream. Cross-sections reveal varying geometries within the modified channel and varying quantities of erosion over a 7-month time period.