The Composition and Distribution of Stream Restoration Activity: An Analysis of Implemenation Rates at Multiple Scales
Open Access
- Author:
- Welch, Amy P
- Graduate Program:
- Geography
- Degree:
- Doctor of Philosophy
- Document Type:
- Dissertation
- Date of Defense:
- February 13, 2019
- Committee Members:
- Brent Yarnal, Dissertation Advisor/Co-Advisor
Cynthia Ann Brewer, Committee Chair/Co-Chair
Denice Heller Wardrop, Committee Member
Erica A H Smithwick, Committee Member
Elizabeth Weeks Boyer, Outside Member - Keywords:
- water quality
stream restoration
nonpoint source pollution
Chesapeake Bay
restoration project database
restoration ecology
stormwater management
best managment practices
Clean Water Act Section 319 - Abstract:
- Nonpoint source (NPS) pollution is both diverse and diffuse, making it difficult to mitigate and a significant threat to waterways. As the estuary with the highest land-to-water ratio in the world, the Chesapeake Bay is particularly vulnerable to this threat. Pennsylvania is the most significant contributor of NPS pollution to the Bay meaning that the state’s mitigation activities play a critical role in Bay restoration efforts. Although understanding the scope, nature and location of these activities are crucial to comprehending their success today and planning more effective mitigation actions in the future, there has not been a recent or comprehensive assessment of them in Pennsylvania. This dissertation addresses this gap by creating a more thorough inventory of stream restoration activity across the state than any previously conducted. It examines the composition and spatial distribution of restoration activity at multiple scales relative to critical pollution sources and water quality management priorities. It also explores the relationship between rates of project implementation and important social and environmental characteristics that may influence project implementation and effectiveness. Results of the spatial analysis indicate that Pennsylvania’s restoration activity is occurring at higher rates in the Chesapeake Bay watershed than in the state’s two other major watersheds and that clusters of activity are aligned with high priority sources of nonpoint source pollution, namely agriculture and urban stormwater runoff. Results from regression analyses show that implementation rates correlate with both social and environmental characteristics, most notably that high levels of activity are strongly associated with areas with higher household incomes and with the proportion of land in the riparian zone that is a source for NPS pollution rather than a sink. These results can help inform future efforts to prioritize the type and location of stream restoration activity, particularly when decision makers and managers are constrained by time and resource.