New Mexico Geological Society Annual Spring Meeting — Abstracts

The many flood control and water resource management dams on the Rio Grande have greatly impacted the river, influencing its sediment transport capacity as well as the patterns of erosion and sediment deposition. This has a large effect on river morphology and the availability of habitat for endangered species such as the silvery minnow. This study aims to identify sediment sources and estimate the flux of sediment delivered to the Middle Rio Grande. To do this, we applied the BQART model to each arroyo watershed that flows into the Rio Grande, beginning with the Cochiti Reach. This empirical model predicts the long-term fluvial suspended sediment flux from river basins based on basin area (A), relief (R), river discharge (Q), temperature (T), and geological/human factors (B). To check the accuracy of this model in a semi-arid ephemeral stream context, we will compare the estimated values to the sediment quantities measured at downstream gauging stations. Quantifying sediment sources and load will help improve our understanding of the effects of sediment transport on river morphology, ultimately providing insight into ecosystem management strategies for preserving habitat for endangered species.