Leveraging Ecosystem Services in Stormwater Management
Research to assist communities with greenspace placement to maximize benefits
Technical BRIEF
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INNOVATIVE RESEARCH FOR A SUSTAINABLE FUTURE
Stormwater Runoff
Many cities need major upgrades to their water
infrastructure, which can be expensive and disruptive to
communities. Impervious surfaces, coupled with outdated
and failing infrastructure, can degrade water quality and
exceed the designed capacity of some stormwater
systems—particularly in combined sewer systems that
collect stormwater runoff, domestic sewage, and
industrial wastewater in one pipe. This can result in
flooding and introduce chemical and microbial pollutants
into surface water and groundwater, causing
environmental and human health concerns.
Greenspace and Stormwater Management
Urban stormwater management is the control of runoff
associated with storm events. One way to manage runoff
is to incorporate green infrastructure practices with
existing traditional gray infrastructure (e.g., storm drains
and pipes) to keep stormwater runoff within the designed
capacity. Green infrastructure leverages the natural
processes of soil and vegetation to slow, capture, and/or
infiltrate stormwater by restoring natural water cycle
processes and keeping it out of collection systems (Fig. 1).
An often-proposed solution for implementing these
practices is to provide greenspace, such as community
parks or gardens, or street trees. Urban greenspace,
regardless of its original purpose, can be factored into
stormwater management plans to help control runoff and
can also provide additional benefits known as ecosystem
services.
Ecosystem Services
Ecosystem services are benefits people receive from
nature that are important to environmental and human
health. They produce the many life-sustaining benefits we
receive from nature—e.g., clean air and water, fertile soil
for crop production, pollination, and flood control. For
example, greenspace with trees can help alleviate air
pollution and noise caused by traffic—air pollutants
adhere to leaf surfaces, which removes them from the air,
and helps block sounds coming from vehicles.
Simultaneously, such greenspace can provide stormwater
Figure 1. An example of a rain garden in St. Louis, MO
(photo from MSD; https://www.projectclearstl.org/get-
the-rain-oiit/ramscaping/)
management benefits because it intercepts rainfall, which
slows the water's movement and allows it to infiltrate
into the soil, thereby promoting the natural water cycle.
Research to Help Communities
Understanding scientifically-verified benefits from
greenspace can aid decision makers, planners, and
residents with how best to incorporate these spaces in
their communities. EPA scientists are developing an
ecosystem services framework and decision-support tools
to assist in choosing where to place greenspace and
demonstrate potential performance. The goal is to help
communities incorporate green infrastructure into their
planning and maximize potential benefits of greenspace.
In the context of stormwater management, the research
is designed to assist stakeholders, decision makers, and
community planners with the following:
•	Prioritize placement of green infrastructure and
greenspace.
•	Incorporate social, economic, and environmental
issues into planning.
•	Involve stakeholders to incorporate diverse
perspectives on community needs and demonstrate
decision outcomes.
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U.S. Environmental Protection Agency | Office of Research and Development
EPA/600/F-19/106 | July 2019

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Ecosystem Services Framework
The ecosystem services framework being developed (Fig.
2) is designed to assist communities in locating
greenspace based on their social, economic, and
environmental needs and concerns. The framework
includes the following to help with placing greenspace
and demonstrating potential performance:
1)	Identifying social, economic, and environmental
concerns and identifying their spatial distribution;
stakeholder involvement is critical at this stage.
2)	Identifying location(s) suitable for installing green
infrastructure or greenspace.
3)	Selecting measurable ecosystem services shown to
address identified needs and concerns.
4)	Determining areas of existing stormwater needs and
other overlapping concerns, and considering
available space, existing land use, etc.
5)	Identifying greenspace types suitable for locations
and capable of providing desired benefits.
6)	Installing greenspace at the location(s) identified.
7)	Measuring and monitoring the system using
indicators to quantify the progress.
Decision-Support Tool
The decision-support tool being developed is built on a
planning support system designed to structure and use
geographic information and computer-based models for
professional planning tasks. It provides a platform for
identifying community problems, conducting suitability
analyses for green infrastructure installation, assessing
ecosystem services, and providing insight into green
infrastructure or greenspace implementation. The basic
functions of the tool include data storage and retrieval,
scenario generation (e.g., installing green infrastructure at
different locations), modeling and visualization, and
feedback into models to support decision-making.
Often used in conjunction with scenario planning
methods, the ability of the decision-support to conduct
what-if scenarios is particularly useful when merged with
the ecosystem services framework. The tool can be used
to assist in developing, assessing, visualizing, and
comparing these scenarios, thereby building consensus
among stakeholders to help them make informed
decisions. For example, a what-if scenario could predict
changes in stormwater discharge based on a 30%
coverage of rain barrels versus a 20% bioswale coverage
at the neighborhood-scale. Because the components
(e.g., framework and models) of the tool can be selected
according to the needs of the ecosystem services
framework, the planning process can provide estimated
Case Study
EPA is collaborating with The City of St. Louis to test the
framework and decision-support tool in St. Louis,
Missouri. The case study is being done to demonstrate
how communities can incorporate social, economic, and
environmental issues and community needs to find the
best placement for urban greenspace using publicly-
available data.
Contacts
Technical Contacts
Matt Hopton, hopton.matthew@epa.gov
Fushcia-Ann Hoover
Xin Fu
Communications Contact
Michelle Latham, latham.michelle@epa.gov
Additional Information
•	Development of a scenario-based stormwater
management planning support system for reducing
combined sewer overflows. Journal of Environmental
Management, 236:571-580 (2019).
•	A runoff trading system to meet watershed-level
stormwater reduction goals with parcel-level green
infrastructure installation. Science of the Total
Environment, 689:1149-1159 (2019).
•	Developing a framework for stormwater management:
leveraging ancillary benefits from urban greenspace.
Urban Ecosystems, doi:10.1007/sll252-019-00890-6
10.1007/sll252-019-00890-6 (2019).
•	Stormwater Management and Green Infrastructure
Research: epa.gov/water-research/stormwater-
management-and-green-infrastructure-research
Landuse
Zoning
Vacant Lots
PM2.5
Emissions
Soil Type
Figure 2. Multiple variables (e.g., land use, vacant lots,
emissions, soils) are examined spatially to identify
locations for maximizing greenspace benefits.
discharge reductions while addressing a community's
socio-economic needs.
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Environmental Protection Agency | Office of Research and Development
EPA/600/F-19/106 | July 2019

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