Stormwater Management Regulations
Duke University, Stormwater Impact Analysis
McAdams has provided stormwater master plan services to Duke University since 2005. The overall Duke University Stormwater Impact Analysis (SIA) was created to give the University an overall analysis model for the main Durham campus. All site plans and projects at Duke are subject to the City of Durham’s local stormwater management regulations. Since 2005, the City’s stormwater regulations have changed numerous times for both peak flow rate detention and water quality, requiring overall updates and changes to the study by McAdams. The campus is broken down into 78 sub-basins for analysis of peak flow rate detention in the 1-year, 2-year, and 10-year storm events for all analysis points in and around the campus. The SIA also covers water quality for nitrogen, phosphorous and total suspended solids. The SIA covers the campus areas in the Cape Fear River Basin, Neuse River Basin, and also the Duke Marine Lab in Beaufort, NC. Each site plan that the University develops, whether a McAdams project or not, must be analyzed in the SIA as part of the site plan permitting process with the City of Durham. The SIA tracks all changes in impervious area and all stormwater runoff for both peak flow rate detention and nutrient export. The study incorporates all stormwater elements of the campus including the Stream and Wetland Assessment Management Park (SWAMP), the Water Harvesting Pond (provides peak flow rate detention and water quality “credits”), multiple cisterns and multiple detention facilities.
The University has also used the SIA for many other projects including analysis of all known impervious areas for the City’s stormwater utility payment, analysis of existing water harvesting systems, analysis of the Duke Water Harvesting Pond (146 million gallons of harvested stormwater annually), feasibility studies for stream mitigation sections, and use in analysis and modeling of individual storm drain conveyance systems.
The Duke University SIA is an ongoing “on-call” project with McAdams and will serve the University for many years to come with its ever evolving comprehensive scope.