2016 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
Institution: Swarthmore College , University of Maryland - Baltimore County , The Johns Hopkins University , Temple University
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, 2015 through September 30,2016
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


Project objectives are to: (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; and (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. Watershed-scale hydrologic modeling – ParFlow.CLM model applied with 40 m x 40 m horizontal by 1 m vertical gridding to the 21 sq km Philadelphia combined sewershed serving the watershed formerly drained by the buried Wingohocking creek.
  2. Site-scale hydrologic modeling – Parflow.CLM model applied with 1.5 m gridding in the horizontal by variable vertical gridding as small as 10 cm near the land surface at two sites in the Wingohocking sewershed that have been selected for installation of monitoring instruments: Wakefield Park and Waterview Recreation Center.
  3. Tensiometer deployment and initial data collection – to measure unsaturated zone tension (suction) head in the vicinity of our monitoring sites in the Wingohocking.
  4. Well drilling and piezometer installation – to install pressure transducers below the water table in the saturated zone is progressing with finalization of piezometer nest design and sensor selection, permissions being obtained, competitive quotes being received from drilling contractors, and coordination with the Philadelphia Water Department.
  5. STEM Education – One University of Maryland Baltimore County (UMBC) Masters student is conducting the hydrologic modeling with ParFlow and will use the results in his thesis. One Ph.D. student at UMBC also is learning hydrological modeling with Parflow and is involved in modeling one of our monitoring sites.
  6. Task 1 publications and presentations – three completed and three in preparation.

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. GreenPhilly Advisory Research Board – several large workshops and small-group meetings held with our project team’s partners leading to two new partnerships with neighborhood community organizations enabling us to further our goal of incorporating the community benefits of GI into our bottom-up modeling framework.
  2. Analytical tools for eliciting and quantifying community benefits from stakeholders – development of a subjective scale for quantifying GI aesthetic and amenity values using visual tools showing images before and after implementation of GI.
  3. STEM education of Temple University undergraduates – 1 summer research course credit plus a full course in the Urban Environment program on urban GI with guest speakers, field trips, and a group policy paper on green infrastructure resulting in one full-time job after graduation, one summer internship with the U.S. Forest Service, and one presentation at an international conference.
  4. Task 2 publications and presentations – two completed and seven in preparation.

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. Simulation with Multiobjective Evolutionary Optimization for runoff reduction benefits of GI – further progress in driving EPA’s Storm Water Management Model Engine hydrologic model with the MOEA engine Borg (Penn State, Cornell), incorporating latest features of both models applied to a prototype watershed and preparing to apply to Philadelphia’s Wingohocking sewershed.
  2. Cost model development – consulting engineers AKRF, Inc., incorporating experience in GI design in Philadelphia CSO area to create statistical regression models for different GI typologies encompassing the range of GI practices installed in Philadelphia.
  3. Geospatial statistics to estimate co-benefits – extending analyses with new data on real estate transactions from 2013 and 2014 and actively developing a need-based index to measure equity as an outcome and operationalize it in the StormWISE model.
  4. STEM education of Swarthmore College undergraduates – four summer research interns hired to work directly on this project plus six case study projects in an engineering course on optimization modeling, with two of these leading to employment after graduation.
  5. Task 3 publications and presentations – one completed and one in preparation.

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. GI benefits quantification and prioritization – incorporation of results from Task 2 into the StormWISE model to generate trade-off analyses for multiple objectives, including maximization of physical water quality benefits in the city’s waterways related to CSO reductions as well as localized community benefits realized in the neighborhoods where the GI practices are deployed.
  2. Web version of StormWISE – evaluation of alternative platforms and selection of a Python-based platform to support interaction with stakeholders, incorporating results from Task 2, and interactive geographic displays facilitating exploration of multiobjective GI benefit and decision spaces.
  3. Stochastic and multi-stage extensions to the StormWISE model – four theoretical models have been developed for modeling the adaptive management process based on the concept of learning, which is realized by updating stochastic coefficients in StormWISE to indicate ways that GI implementation strategies can be improved over time.  These models can be used to specify an optimal investment strategy to pursue in the present while accounting for the potential of adaptive management to adjust strategies so as to achieve improved outcomes in the future by incorporating knowledge gained through early deployments of GI.
  4. STEM education with Johns Hopkins University graduate students – one Ph.D. student’s dissertation research relates directly to Tasks 2 and 4, and several groups of graduate students have participated in mock exercises to help evaluate tools for quantification of community benefits of GI.
  5. =Task 4 publications and presentations – two completed.

Future Activities:

  1. Completion of sensor installation and continuation of data collection from field sites in Philadelphia along with continued hydrologic modeling and comparisons with monitored data and improvements in StormWISE model capabilities to model subwatershed runoff reduction resulting from GI.
  2. Community engagement activities associated with Task 2 will proceed by creating partnerships in additional Philadelphia neighborhoods and further development of tools to quantify and prioritize community benefits and work on an equity index for urban GI will continue.
  3. Statistical, simulation, and evolutionary optimization modeling will be combined to create benefit functions incorporating community input and further developments in our equity index, moving from prototype models to models implemented in the Philadelphia CSO area.
  4. Building on tools developed during years 1 and 2 for quantifying and prioritizing GI benefits and costs, StormWISE extensions will be implemented in the Philadelphia CSO area, including an interactive user interface to improve its ability to inform stakeholders about GI benefits, costs, and necessary tradeoffs, and inclusion of theoretical developments related to the two-stage stochastic model for integrating adaptive management into the modeling framework.

Journal Articles on this Report : 1 Displayed | Download in RIS Format

Other project views: All 56 publications 5 publications in selected types All 5 journal articles
Type Citation Project Document Sources
Journal Article Heckert M, Rosan CD. Developing a green infrastructure equity index to promote equity planning. Urban Forestry & Urban Greening 2016;19:263-270.
abstract available   full text available
R835555 (2016)
R835555 (2017)
R835555 (Final)
  • Full-text: ScienceDirect-Full Text HTML
  • Abstract: ScienceDirect-Abstract
  • Other: ScienceDirect-Full Text PDF
  • Supplemental Keywords:

    Green infrastructure community benefits

    Relevant Websites:

    GreenPhilly Research Group Exit

    Progress and Final Reports:

    Original Abstract
  • 2014 Progress Report
  • 2015 Progress Report
  • 2017 Progress Report
  • Final Report