Total maximum daily load (TMDL) goals to reduce sediment and nutrient pollution drive much of the stormwater management activity throughout the Chesapeake Bay watershed, resulting in urban and agricultural best management practices (BMPs) implemented to target these pollutants. These BMPs, however, may provide ancillary benefits beyond sediment and nutrient reduction.
The Center for Watershed Protection (CWP) led a project to examine BMP co-benefits for reducing stressors to stream health additional to sediment and nutrients. The study built on prior work conducted by the USGS to identify key stressors to biotic stream health. These include toxics, flow, salinity, pesticides, and geomorphology/habitat.
A literature review and synthesis were conducted on a subset of BMPs implemented throughout the Bay watershed to assess the capacity for each BMP to improve each stressor. Results indicated a variety of BMPs are effective at reducing the stressors pesticides and other toxics via sedimentation and infiltration mechanisms. These include urban wet ponds & wetlands, bio-infiltration, vegetated buffers and agricultural wetlands. The geomorphology/habitat stressor can be improved through direct modification (e.g., stream restoration) or via reduced sediment loading to the stream. Flow was found to be a key factor in long-term success of geomorphology improvements, with wet ponds & wetlands, bio-infiltration and tree planting the most effective for mitigating flow stressors. All structural BMPs considered showed limited capacity to mitigate salinity. Combinations of BMPs are likely required to effectively mitigate the multiple stressors driving poor stream health.
This study provided a comprehensive understanding of the effect of BMPs on stressors to stream health and enables realistic expectations of co-benefits. This study also identified research gaps and serves as a guide for improving future monitoring efforts.
- Upon completion of this course, attendees should be able to:
- Analyze the relationship between specific BMPs and their effectiveness in mitigating different stressors affecting stream health
- Evaluate co-benefits of BMP’s
- Explain existing research gaps and apply a roadmap for enhancing monitoring efforts
Travis Ostrom, PE, PhDWater Resources EngineerCenter for Watershed Protection
Travis is a Water Resources Engineer with the Center for Watershed Protection (CWP), where he focusses on stormwater management. Travis holds a Ph.D. in civil and environmental engineering from the University of Maryland and is a registered professional engineer (P.E.) in Virginia and Maryland. He has broad knowledge in civil and environmental engineering with experience in the U.S and abroad, including as a Peace Corps volunteer in Honduras. Travis has also taught undergraduate environmental engineering courses as a Lecturer at the University of Maryland. His research expertise is in best management practices for urban stormwater treatment.
Lisa Fraley-McNealSenior Watershed and Stormwater Research SpecialistCenter for Watershed Protection
Lisa Fraley-McNeal is a Senior Watershed and Stormwater Research Specialist at the Center for Watershed Protection with over 17 years of experience. Her areas of expertise include GIS and field methods for watershed assessment, watershed planning, stream restoration, Chesapeake Bay TMDL crediting, and applied research on topics related to watershed and stormwater management. She served as one of the Sediment and Stream Corridor Restoration Coordinators for the Chesapeake Bay Program and helped with development of the Stream Restoration Expert Panel Recommendations and subsequent workgroup updates. She has a B.S. degree in Geography and Environmental Systems, with a writing minor and cartography certificate from the University of Maryland, Baltimore County. Lisa also has a M.S. degree from the University of Maryland, Baltimore County in Marine and Estuarine Environmental Science and is currently working on her graduate GIS Certification at NC State Universit