The Tools in Our Green Infrastructure Toolkit

By Michaela Burns 

Almost everyone has a story to share about storms.  Maybe it rained so hard one day that you stayed inside curled up by the fireplace. Maybe it caused a power outage that left you and your family playing board games by flashlight. When I think about storms, I always think about the clogged drains that kept brown stormwater filled with trash on the sidewalks of Manhattan. My childhood friends and I would make a game of dancing over these large puddles. As an adult it became something I warily sidestepped to protect my shoes.

That water is called stormwater runoff, which is rain water that picks up chemicals, metals, and other debris as it travels to the sewers. Hundreds of cities in the U.S. like New York and Chicago use a combined sewer system to move stormwater runoff and wastewater away from urban centers and to treatment plants. During heavy storms, excess water overflows the system and sewage is sent straight to nearby water sources. These overflows are called combined sewer overflows (CSOs) and they are a major water pollution concern for cities. In New York, for example, more than 27 billion gallons of sewage and polluted stormwater contaminates the Hudson River each year.rain drops with info on each tool

EPA supports the use of green infrastructure (e.g. green roofs, permeable parking lots, rain gardens) because it can help reduce the amount of stormwater contaminating our water sources and prevent erosion and flooding that can damage infrastructure and the environment. EPA researchers have developed different green infrastructure models and tools to help communities with stormwater management. An upcoming EPA webinar will present a modeling toolkit consisting of five such resources and additional communication material that can be used to help implement certain green infrastructure practices. The models and tools in this toolkit include:

  • Green Infrastructure Wizard (GIWIZ) – GIWIZ is a web application that provides communities with information on EPA green infrastructure tools and resources.
  • Watershed Management Optimization Support Tool (WMOST) – WMOST is a software application that allows water resource managers and planners to screen a wide range of management practices for cost-effectiveness and economic sustainability.
  • Visualizing Ecosystem Land Management (VELMA) Assessments– VELMA is a computer software model that regional planners and land managers can use to determine which green infrastructure practice would be most effective for improving water quality in streams, estuaries, and groundwater.
  • Storm Water Management Model (SWMM)-The SWMM is a simulation model that communities can use for stormwater runoff reduction planning, analysis, and the design of combined sewers and other drainage systems.
  • The National Stormwater Calculator (SWC) – The SWC is a desktop application that estimates the annual amount of rainwater and frequency of runoff from a specific site anywhere in the United States (including Puerto Rico). Users can use SWC to learn about the ways that green infrastructure technology like rain gardens can prevent water pollution in their neighborhoods.

Register now for this webinar on Wednesday, October 26th at 2:00 pm ET to learn from EPA researchers how these tools can help you incorporate green infrastructure into your community. Or discover the green infrastructure modeling toolkit on your own time.

About the Author: Michaela Burns is an Oak Ridge Associated Universities contractor and writer for the science communication team in EPA’s Office of Research and Development.

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