Assessing and Improving Pollution Prevention by Swales Status: CompleteReport Date: 08/18/2014 Summary: Roadside drainage ditches, or swales, were found to enable stormwater infiltration significantly more efficiently than anticipated based on published values for Minnesota soil types, although infiltration rates varied by large amounts within a swale. A follow-up project will develop a tool to calculate real-world infiltration rates in swales, which MnDOT hopes will be used in determining stormwater management credits. That may reduce the need for other stormwater management practices, potentially saving significant construction and right of way acquisition costs. Final Deliverables: Report #2014-30 Research Summary Related Materials: How Roadside Drainage Ditches Reduce Pollution - (Blog Post) Related Research: Iron-Enhanced Swale Ditch Checks for Phosphorus Removal
