Drainage Scale Dependency of River Sensitivity to Environmental Change: Tools for Planning Under Uncertainty

EPA Grant Number: F13B20350
Title: Drainage Scale Dependency of River Sensitivity to Environmental Change: Tools for Planning Under Uncertainty
Investigators: Sholtes, Joel
Institution: Colorado State University
EPA Project Officer: Lee, Sonja
Project Period: August 1, 2014 through August 1, 2016
Project Amount: $84,000
RFA: STAR Graduate Fellowships (2013) RFA Text |  Recipients Lists
Research Category: Academic Fellowships , Fellowship - Hydrology

Objective:

At the most general level, this research explores river responses to changes in the drivers of flow and sediment supply. Findings will help understand how scale influences this response or sensitivity; that is, where within a watershed are streams and rivers most sensitive to environmental change?

Approach:

To study river sensitivity to change, the project first considers qualitative and semiquantitative river response models, which indicate the direction of channel response as a function of changes in the drivers of flow and sediment, as well as the current flow and sediment regime. It uses a sediment continuity model implemented at various points within case study watersheds to characterize the sensitivity of the sediment balance to changes in flow regime and sediment supply. The flow regimes and sediment loads to these models (e.g., increase flow variability or curtail flood peaks) will be perturbed to analyze how sensitive the sediment balance is at various points within a watershed. This work will be conducted in both snowmelt-driven and convective precipitation-driven watersheds.

Expected Results:

EPA has called for a “strategic” and “systems” approach to identify priority watersheds for protection and restoration, highlighting a lack of understanding of the geography of sensitive and resilient zones within a watershed as a key research gap. This research will produce a framework that addresses the research and decision tool needs by identifying the magnitude and scaling behavior of geomorphic sensitivity to environ- mental change within a watershed and by creating a methodology that can be used in other settings to identify river sensitivity to environmental change.

Potential to Further Environmental/Human Health Protection

This work will help managers target limited watershed protection and restoration resources. As a general tool, the model can be applied at various points within a watershed representing similar geomorphic settings. This framework also can help managers identify which river settings and drainage scales may not meet their designated uses in the future due to habitat alteration and sedimentation caused by environmental change.

Supplemental Keywords:

environmental change, rivers, sediment

Progress and Final Reports:

  • 2015
  • Final