Sediment Transport Dynamics in a Complex Fluviokarst System, South-central Kentucky

Sediment transport dynamics in a complex fluviokarst system, south-central Kentucky Background and Objectives Sediment is known to be the most common contaminant of rivers and streams, but it also plays a major role in the transport, deposition, and resuspension of other contaminants. These same processes of sediment and contaminant flux are at work in fluviokarst settings, where groundwater and surface water are intricately connected. Understanding sediment transport in fluviokarst settings is vital for assessing aquifer vulnerability; however, prior studies rely on measurements of suspended load and calculations based on fluid dynamics rather than measuring both suspended load and bedload to quantify flux. The need for improved understanding of sediment flux is increased by the predicted local and regional impacts of climate change. Although the mean annual precipitation is predicted to remain relatively similar to current values in Kentucky, storms will be less frequent and much more intense. These changes can result in a dramatic increase of sediment production and discharge due to increased surface runoff and sediment mobilization. Focused on Sal Hollow, an isolated fluviokarst system in Mammoth Cave National Park, and using high-resolution continuous monitoring of suspended load and bedload, this project aims to quantify current sediment transport dynamics and identify the primary drivers of sediment flux. Understanding current sediment dynamics in the region will help mitigate future threats such as degradation to water quality and downstream ecosystems, and flood risk.