Modeling the Effects of Green Stormwater Infrastructure Implementation on Urban Hydrology and Urban Heat Islands in Illinois

Our research indicates that the Community Earth System Model’s (CESM) hydrologic modeling capabilities regarding runoff are spatially “robust”, or perform acceptably well under a range of possible conditions. When averaged annually, CESM’s projections correlated well with a groundtruthed observational dataset, University of New Hampshire-Global Runoff Data Centre (UNHGRDC), and a reanalysis dataset from NASA, Modern-Era Retrospective analysis for Research and Applications, Version 2 (MERRA-2), but there are still prominent areas where CESM is not as strong in accurately predicting runoff compared to UNHGRDC and MERRA-2. After this validation was completed, we moved to bridging the local-scale U.S. Environmental Protection Agency Stormwater Management Model (EPA-SWMM) to the global scale CESM to respresent and parameterize widespread green stormwater infrastructure (GSI) implementation. We identified three relevant parameters and their corresponding calibrated values that could be used as inputs into the land component of CESM: saturated hydraulic conductivity, maximum ponded depth, and porosity. We have developed a parameterization implementing these values into the top 6 layers of the urban land model component of CESM, representing the depth of a rain garden, and are preparing simulations. Our ongoing work focuses on simulating GSI in CESM in 30 U.S. cities with combined sewer overflow issues; three of these cities are located in Illinois.

  • PI: Lei Zhao
  • PI Institution: University of Illinois
  • March 1, 2020 – December 31, 2021