Watershed Nutrient Pollution Dynamics Under Extreme Events in the Cape Fear River Watershed, North Carolina
Abstract
Ongoing climate change brings more frequent and intense rain events, and more pronounced droughts, with distinct consequences for water quantity and quality that put aquatic systems and people at risk. Large storms flood communities, disrupt water distribution and treatment infrastructure, and broadcast pollutants over extensive areas. Dry periods reduce available water supplies, concentrate pollutants in stream, and are associated with harmful algal blooms. Developing adaptive programs and policies to protect water quality will require a better understanding of the relative risk from both point and non-point sources under a variety of conditions. We examine these issues in the ~9,700 mi2 Cape Fear River Watershed in North Carolina. The Cape Fear River was recently ranked among the ten most endangered rivers in the United States and >2 million people depend on this river system for drinking water. The watershed has undergone recent rapid urbanization as well as agricultural intensification, including expansion of concentrated animal feeding operations. To identify and track nutrient pollution hotspots, we developed a Soil And Water Assessment Tool model incorporating contemporary land use and land cover, reservoir and floodplain wetland functions, point and non-point sources (e.g., fertilizer and manure applications). We examined water quality under observed weather conditions 1979-2019, capturing multiple hurricanes and drought events, including four 500-year hurricane events that occurred 2016-2019. Results highlight regions that merit further evaluation for strategies to avoid or mitigate damage to vulnerable human communities and natural systems.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2021
- Bibcode:
- 2021AGUFM.H15I1150S