Calculating the Future with Green Infrastructure

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EPA Administrator Gina McCarthy speaking at the National Council for Science and the Environment. Photo credit: John Mcshane


In his State of the Union address, President Obama said “the nation that goes all-in on innovation today will own the global economy tomorrow.” He made the point that science and research are critical to keeping that competitive edge—but also to protecting our public health and our environment. I couldn’t agree more.

Science has always been at the heart of our mission at EPA. In the State of the Union address, President Obama doubled down on his commitment to using science to address a changing climate and carry out his Climate Action Plan—which aims to curb carbon pollution, build climate resilience in our towns and cities, and lead the world to a sustainable, clean energy future.

EPA science is critical to each part of the plan—and one of those ways is through our newly updated National Stormwater Calculator to help build climate resilience in our towns and cities.

The Calculator is a desktop application that estimates the annual amount of stormwater runoff from a specific location, based on local soil conditions, slope, and land cover. The new climate change update gives us the added ability to look at how runoff may change in the future based on historical weather data and different future climate change scenarios.

Here’s why that’s important. A lot of places in our communities, like a person’s home, have solid surfaces such as a concrete patio or a driveway. Stormwater running off those places picks up contaminants like pesticides and road salt on its way to the storm drain. With a greater frequency of extreme weather events, that pollution eventually reaches our lakes, rivers, and beaches.

But using the Calculator, local leaders and the general public can enter the address of a location and choose different scenarios and learn how adding green infrastructure elements—like rain barrels and rain gardens—can reduce the polluted runoff.

The updated Calculator (or phase II of the National Stormwater Calculator and Climate Assessment Tool package) takes it one step further by allowing users to select climate scenarios that incorporate changes in seasonal precipitation levels, the effects of more frequent high-intensity storms, and changes in evaporation rates. Once a climate scenario is chosen, the Calculator presents data on how well the selected green infrastructure element could handle runoff in future years.

When I travel around the country, I hear from mayors and local officials all the time about the hardships felt throughout their neighborhoods when it comes to poor water quality and water infrastructure badly in need of renewal. The updated Stormwater Calculator is a tool in those mayors’ hands give them the chance to find out what solutions best fit individual properties in their city—without breaking the bank. Towns and cities can harness the benefits of green infrastructure, combined with other elements of Presidents Obama’s Climate Action Plan, to help prepare for climate impacts and built a cleaner, healthier future.

From protecting our water to combating climate change, the environmental protection challenges we face are steep, and now more than ever we have to continue to rely on science as our guide. As President Obama said in his State of the Union address, in the future when our kids “look us in the eye and ask if we did all we could to leave them a safer, more stable world”… we all want to be able to say “yes, we did.

Sound science, like the science that goes into the Stormwater Calculator, will help get us there.

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