From streams to seas: Using community-based science to track the source and fate of marine debris from a mixed-use watershed

Abstract
Marine debris (MD) has profound negative impacts on vital coastal ecosystems, including the Delaware River. Yet, few studies have investigated MD delivery to rivers, despite their substantial role in transporting MD to the ocean. Watersheds provide an opportunity to examine causal factors that deliver MD to the coast and allow local stakeholders to understand the interconnectedness between clean water issues and thriving communities.

We will monitor MD delivery to and from the Tookany/Tacony-Frankford (TTF) Watershed, a direct tributary of the Delaware River, by: 1) surveying MD in riparian buffers of headwater tributaries; 2) coring riparian buffers and ponded areas to determine microplastic (MP) retention rates; and 3) comparing MD loading across political boundaries (suburban vs. Philadelphia) and to the Delaware River. MD loads will be calculated with mass-balance analyses of MD along the mainstem before and after storm events and GoPro camera deployment during storm events at two USGS gauging stations in the watershed.

We will examine the role of restoration efforts, such as the efficacy of vegetated riparian buffers in trapping MD to evaluate litter prevention strategies. This research will be collaboratively conducted with TTF Watershed Partnership, a vibrant organization focused on restoration, stewardship, and advocacy throughout this ~78-km2 suburban-urban ecosystem.

We will engage an existing network of volunteers, incorporate community events and outreach with local schools to support data collection. These citizen science components will increase societal engagement around MD. The project will provide funding for two MS students, four undergraduate students, and will engage additional undergraduate/graduate students in our courses.

Finally, the project will result in two scientific publications; a protocol for monitoring MD in the TTF watershed; and actionable steps for engaging communities along the watershed to reduce MD to the vital Delaware River watershed ecosystem.