2014 Progress Report: Performance and Effectiveness of Urban Green Infrastructure: Maximizing Benefits at the Subwatershed Scale through Measurement, Modeling, and Community-Based Implementation

EPA Grant Number: R835555
Title: Performance and Effectiveness of Urban Green Infrastructure: Maximizing Benefits at the Subwatershed Scale through Measurement, Modeling, and Community-Based Implementation
Investigators: McGarity, Arthur E , Hobbs, Benjamin F. , Rosan, Christina , Welty, Claire , Heckert, Megan , Szalay, Shandor
Current Investigators: McGarity, Arthur E , Hobbs, Benjamin F. , Rosan, Christina , Welty, Claire , Heckert, Megan
Institution: Swarthmore College , AKRF, Inc. , The Johns Hopkins University , Temple University , University of Maryland - Baltimore County
Current Institution: Swarthmore College , Temple University , The Johns Hopkins University , University of Maryland - Baltimore County
EPA Project Officer: Packard, Benjamin H
Project Period: October 1, 2013 through September 30, 2017 (Extended to September 30, 2018)
Project Period Covered by this Report: October 1, 2013 through September 30,2014
Project Amount: $1,000,000
RFA: Performance and Effectiveness of Green Infrastructure Stormwater Management Approaches in the Urban Context: A Philadelphia Case Study (2012) RFA Text |  Recipients Lists
Research Category: Watersheds , Water


The project objectives are as follows:

  1. Evaluate selected green infrastructure (GI) demonstration projects in the Philadelphia combined sewer overflow (CSO) area.
  2. Develop methodology for creating zones of green infrastructure (ZGIs).
  3. Develop quantitative GI benefit-investment functions for each zone.
  4. Incorporate benefit functions into tools for use by municipal officials and community stakeholders.
  5. Incorporate STEM learning at multiple levels.

Progress Summary:

Task 1. Subsurface modeling and monitoring; outputs – refined methodologies for performance assessment of GI practices at the site and watershed levels; outcomes: increased national capability for assessing and implementing GI practices.

  1. QAPP Report QA/QC for field monitoring approved by EPA.
  2. Four sites selected for subsurface monitoring below installed GI practices.
  3. Selected the ~21 sq. km Wingohocking watershed in N. Philadelphia for application of the Parflow coupled groundwater-surface water model.
  4. A model drainage test gridded at 20 m x 20 m in the horizontal and 1 m in the vertical was conducted to ensure that the model drained properly upon input from precipitation. 
  5. Instrument testing:  three TS1 tensiometers manufactured by UMS were purchased for testing, a Campbell-Scientific data logger was rented, and procedures and materials/ supplies required for deploying pressure transducers in small piezometers were determined.
  6. Well installation: bids from four well drillers were obtained in spring of 2014; coordination with Villanova’s STAR project on permissions issue; handheld drilling apparatus owned by UMBC has meanwhile been used to drill a test well by hand in the Maryland Piedmont to a depth of 14 ft. with a well screen of 1 ft. in the Maryland Piedmont to determine the quantitative requirements for optimal placement of well points in the vertical so as to be able to discern vertical hydraulic gradients with Hobo pressure transducers.

Task 2. Philadelphia Community Engagement through Research Partnerships; outputs – refined methodologies for evaluation of cost effective GI implementation strategies using a bottom-up modeling process; outcomes – enhanced prospects for widespread successful implementation of green infrastructure.

  1. The GreenPhilly Community Advisory Board was formed consisting of representatives from Community Development Corporations (CDCs), environmental and other non-profits, and Philadelphia City Agencies and two workshops were held, introducing the research goals and discussing benefit metrics to include in our green infrastructure model.
  2. STEM education included involvement of undergraduate research assistants to conduct literature reviews and teaching an Urban Environment class at Temple University on the theme of green infrastructure.

Task 3. Develop benefit functions for Direct Benefits and Co-Benefits of Green Stormwater Infrastructure; outputs – refined methodologies for accurate life-cycle assessment of GI practices employing multiple benefit metrics including direct benefits and co-benefits; outcomes – increase national capabilities for implementing GI practices at the subwatershed level.

  1. Successful coupling of Penn State’s Borg optimization engine to EPA’s Storm Water Management Model (SWMM) simulation model and generation of benefit functions for a realistic example watershed used in the SWMM Applications Guide.
  2. Geospatial Statistics to Estimate Co-Benefits - literature review of impacts of parks, gardens, greenspaces, and green infrastructure on surrounding communities; determined a methodology for assessing impacts on property values; obtained a database of all residential real estate transactions in Philadelphia between 2000 and 2013 for use in modeling impacts on property values.

Task 4. Develop a Stochastic and Multi-Stage StormWISE Model; outputs – refined methodologies for incorporation of uncertainties and an adaptive management process in modeling GI investment strategies; outcomes – increased national capabilities for cost-effective and adaptive implementation of GI practices for urban stormwater management at the subwatershed scale.

  1. A web version of the StormWISE model was developed and demonstrated for use in seeking guidance on future model development from the research team and the Community Advisory Board.
  2. A modeling subgroup consisting of project investigators at Swarthmore and Johns Hopkins was formed to develop extensions to the StormWISE model to enable modeling of uncertainties in GSI performance and cost parameters and to incorporate multiple stages enabling modeling of adaptive decision making to reduce risks through learning over time.

Future Activities:

  1. Sensor installation and monitoring activities will begin at our selected GSI sites in Philadelphia.
  2. Community engagement activities will proceed by creating two or more smaller advisory groups focusing on (1) issues relating to the equitable distribution of GSI co-benefits and (2) technical issues relating to modeling of GSI benefits and costs.
  3. Further development of the concept of geographic ZGIs will proceed, moving from prototype models to models implemented in the Philadelphia CSO area.
  4. Build upon the theoretical framework developed during Year 1 to begin implementation of StormWISE model extensions to the Philadelphia CSO area.

Journal Articles:

No journal articles submitted with this report: View all 56 publications for this project

Supplemental Keywords:

green infrastructure, modeling, stormwater management, urban, watershed

Relevant Websites:

GreenPhilly Research Group Exit

Progress and Final Reports:

Original Abstract
  • 2015 Progress Report
  • 2016 Progress Report
  • 2017 Progress Report
  • Final Report