Bioretention Design Webinar

This two-day virtual training covers advanced bioretention design for stormwater management based on the Iowa Stormwater Management Manual. Participants will learn about bioretention cells, bioswales, and tree trenches from experienced Iowa practitioners, including critical design elements, pretreatment strategies, enhanced pollutant removal techniques, and vegetation selection. The workshop explores proven inspection and maintenance approaches to ensure long-term performance and visual appeal, with real-world case studies demonstrating lessons learned and how field experience has informed current best practices.

Learning Objectives

By the end of this workshop, participants will be able to:

• Identify bioretention options in the Iowa Stormwater Management Manual and their applications in urban areas
• Apply simple to multiple cell bioretention cell, tree filter box, and bioswale designs including pretreatment options and design review checklists
• Incorporate enhanced pollutant removal practices to meet local water quality protection goals
• Select appropriate vegetation including layout and establishment considerations
• Apply lessons learned from Iowa case studies including recommendations for inspection and maintenance to ensure long-term performance

Professional Development Hours

Attendees will earn 6 PDHs for completing the full two-day workshop (3 PDHs per day). Single-day registration is also available.

Day 1: May 6, 2026

8:30-8:40 | Welcome and Opening Remarks
Pat Sauer, ISWEP

8:40-9:30 | Bioretention Options, Function, and Applications
Ann Seda, IDALS Urban Conservationist

9:30-10:30 | Bioretention Cell Design: Single Cells, Multiple Cells, Detention, and Hydrologic Considerations
Craig Clarkson, PE, Sherwood Engineers

10:30-10:45 | Break

10:45-11:15 | Tree Filter Boxes and Bioswales
Aaron Gwinnup, PE, RDG

11:15-11:45 | Pretreatment Options
Aaron Gwinnup, PE, RDG

11:45-12:00 | Day 1 Wrap Up and Discussion
Pat Sauer, ISWEP

Day 2: May 7, 2026

8:30-9:00 | Subsurface Drainage: Is It Always Needed? Lessons from Minnesota Research
Loulou Dickey, PhD, ISWEP and Aaron Gwinnup, PE, RDG

9:00-10:00 | Enhanced Pollutant Removal: Nitrogen, Organic Contaminants, and Media Selection
Aaron Gwinnup, PE, RDG; Greg LeFevre, PhD, University of Iowa; Loulou Dickey, PhD, ISWEP

10:00-10:15 | Break

10:15-10:45 | Vegetation Selection, Layout, and Establishment
Jennifer Welch, Polk SWCD

10:45-11:15 | Installation Case Studies and Lessons Learned
Aaron Gwinnup, PE, RDG

11:15-11:55 | Short and Long-Term Inspection and Maintenance
Pat Sauer, ISWEP

11:55-12:00 | Wrap-Up and Closing Comments
Pat Sauer, ISWEP

Registration

ISWEP members receive a discount on registration. If you need your discount code, email iswepadmin@iowastormwater.org.

Register here!

Questions?

Contact iswepadmin@iowastormwater.org for more information about this workshop.