Optimization of Green Infrastructure Practices

Project Title: A framework for optimization of green infrastructure practices selection and placement to attain runoff and water quality goals in urban watershed

Principal Investigator(s): Dr. Jingqiu Chen, Purdue University, Department of Agricultural &
Biological Engineering

Project Staff/Co-Investigator(s): Dr. Bernard A. Engel, Purdue University, Associate Dean and
Director for Agricultural Research and Graduate Education, and Department of Agricultural and
Biological Engineering; Dr. Margaret W. Gitau, Purdue University, Department of Agricultural and
Biological Engineering

Dates: March 1, 2020 – February 28, 2021

Total Federal Funds:  Total Non-Federal Funds:

Project Reports
Project Factsheet

Dr. Gary Lamberti

Combined sewer overflows (CSO) are considered as threats to human health and the environment. Untreated wastewater and stormwater released by CSO into surface waters is typical in many urban areas in Indiana, which poses a strong need for wastewater improvements in the state of Indiana. Green infrastructure (GI) practices are on-site stormwater management approaches that increase infiltration and storage, delay runoff peaks, reduce runoff rates and volumes, and control the movement of pollutants. Computer-based hydrological models can perform temporal and spatial simulations of the effects of hydrologic processes and management activities on hydrology and water quality. The Long-Term Hydrologic Impact Assessment (L-THIA) model is a user-oriented tool that requires only data on hydrologic soil groups, land use, and long-term precipitation (typically 30 years or more) to estimate surface runoff changes. The L-THIA-Low Impact Development (L-THIA-LID) model integrates GI practices into a L-THIA model and has been successfully used to assess the impacts of GI practices on surface hydrology and water quality. Prior study by the investigators regarding the evaluation of the effectiveness of GI practices on improving hydrology and water quality and their associated costs provided valuable information for decision makers such as urban planners, watershed managers, and city sanitary managers when creating development/re- development strategies. This proposal outlined an optimization work that would facilitate achieving optimal benefits considering budget and environmental objectives. The optimization outcomes of this proposed work on GI practices selection and placement would be useful for urban watershed to attain runoff and water quality reduction goals, which is also increasingly needed by many urban areas in Indiana.