New Mexico Geological Society Annual Spring Meeting — Abstracts

Extreme runoff events across the southwestern U.S. deliver large sediment loads that can cover infrastructure and alter the landscape. Predicting how this sediment moves during these flash floods can reduce uncertainty in sediment predictions and better support planning for infrastructure, reservoir management, and flood risk, thereby helping communities prepare for extreme sediment events. This prediction can prove difficult because water levels rise quickly and unpredictably, making it hard to collect data from this environment.

This study aims to address a gap in model validation by testing the AdH model, along with the sediment transport library (SEDLIB), using detailed field data from the Arroyo de los Pinos (ADLP). This ephemeral stream flows into the Rio Grande in central New Mexico. The ADLP has collected continuous bedload and hydrologic data since 2018, which enables thorough model testing. While models like AdH, in theory, can predict sediment transport, they are usually used for large coastal rivers and aren’t often utilized in dry, sand-rich gravel-bed channels. The main goals of this study are to assess whether AdH, when configured for dry, sand-rich gravel-bed channels, can accurately predict bedload transport during monsoon flash floods and to establish standards for sediment transport modeling throughout the Southwest.