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Addressing America’s Largest Growing Source of Water Pollution: Stormwater Runoff

Mike M. McMahon | May 31, 2016
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On May 11, more than 100 thought leaders and policymakers gathered in downtown Chicago at the Great Water Cities 2016 Summit to discuss the largest growing source of water pollution in the United States—stormwater runoff. The summit, hosted by the Water Environment Federation (WEF), built on the findings in the report Rainfall to Results: The Future of Stormwater, which was published by WEF’s Stormwater Institute in late 2015. During the summit, participants discussed the dire need for infrastructure improvements as well as creative ways to fund such projects in the face of limited public dollars. 

Stormwater Runoff: What is it, and why does it matter?

When rain falls on undeveloped landscapes, it typically soaks into the soil or is returned to the atmosphere by plants or evaporation. However, in most urban areas, when rain falls on our impervious roofs, streets, and parking lots, as much as 55 percent of the water is unable to soak into the ground, according to the U.S. Environmental Protection Agency (EPA). This stormwater, known as “runoff,” often collects trash, bacteria, heavy metals, pesticides, animal waste, and other pollutants as it flows through the urban landscape.

Many cities in the United States utilize a combined sewer system, which collects untreated runoff, domestic sewage, and industrial wastewater into one sewage pipe. Under normal conditions, this water is channeled to sewage treatment plants to be treated and discharged to nearby bodies of water. However, when the volume of this water exceeds the capacity of the system (e.g. during heavy rainfall), it is discharged directly, with little or no treatment.

In the report Rainfall to Results, WEF’s Stormwater Institute highlights the difficulties associated with stormwater management: “The… nature of stormwater makes responsibility for its treatment and control hard to assign. Stormwater discharge, volume, and quantity are intimately tied to land use. Human actions—from industrial processing and largescale construction down to mowing lawn or picking up after pets—all affect stormwater quality.”

The Need for Increased Investment

Much of the infrastructure used to manage stormwater in the United States is antiquated, requiring an estimated $67-77 trillion in improvements, according to Prisca Weems, Stormwater Manager for the City of New Orleans. Such a large investment is unprecedented, given that combined federal, state, and local government spending on water utility infrastructure over the last 35 years has only totaled $3 trillion, according to the U.S. Congressional Budget Office. To deal with the water quality and quantity effects of runoff, many communities are seeking to upgrade their “gray” infrastructure (conventional gutters, storm sewers, tunnels, pipes, mechanical devices, etc.) while also investing in “green” infrastructure. Green infrastructure mimics nature by capturing rainwater so it can be reused, temporarily retained, or allowed to seep into the soil, rather than flowing into sewer systems. Examples of green infrastructure include rain gardens, pervious pavement, planted trenches, green roofs, and storage containers such as rain barrels.

While some communities and utility companies are implementing creative solutions to stormwater management, experts at the Great Water Cities Summit stressed the lack of funding for such costly overhauls. “In the transportation industry, 85 percent of the money for highways comes from the federal government, and in the water business it’s about 3 percent…The bottom line is there’s very little money for this stuff… and there’s a lack of political will in many areas of the country to raise rates,” explained Howard Neukrug, former CEO of Philadelphia Water and Senior Fellow at U.S. Water Alliance.

“We need to work across wastewater and stormwater and figure out what our biggest priorities and risks are. Every possible partner that’s out there needs to be brought together to see how we can leverage resources and find common ground. Because there is no more money. The money you see is the money we have. We’ve got to figure out how to work together. Otherwise, we’ll still be talking about these same issues 30 years from now,” Neukrug said.

Karen Sands, Director of Planning, Research, and Sustainability at the Milwaukee Metropolitan Sewerage District, echoed the challenges concerning funding projects in her region: “If we’re going to meet our goals, we need to increase spending by 18 times… [We have a goal] of installing 740 million gallons of green infrastructure capacity by the year 2035. At that rate, we need to add 36 million gallons per year. Over the past 10 or 12 years, we’ve only added 21 million gallons altogether. So we have to ramp up significantly.” 

The largest source of federal funding for stormwater management comes from EPA’s Clean Water State Revolving Fund (CWSRF). The CWSRF provides low-interest loans to states for water infrastructure projects and asks states to contribute an additional 20 percent to match the federal grant amount. 

“There are definitely federal funds available, but it might not be a lot. The [CWSRF’s] contribution annually is about $8 billion,” explained Andrew Sawyers, Director of EPA’s Office of Wastewater Management. Despite the relatively small pool of federal dollars, the low interest rate associated with CWSRF funds is attractive to project implementers. “The average interest rate on a [CWSRF] loan last year was 1.8 percent, while the average market interest rate was about 4.2 percent. That’s a pretty significant spread,” Sawyers said.

Public-Private Partnerships

Given the need for costly industry improvements and limited public funding, many summit participants pointed to public-private partnerships as a possible way to fill the shortfall.  

Former Virginia Secretary of Natural Resources Preston Bryant pointed to The Clean Water Partnership between Prince George’s County, Maryland and Corvias Solutions as an example of a successful public-private project. The 30-year partnership seeks to retrofit up to 4,000 acres of impervious surfaces using green infrastructure. Corvias is responsible for both the initial development and the long-term maintenance for the project in addition to driving economic development by using local, small, and minority businesses for at least 30 to 40 percent of the total project scope.

“Risk sharing is at the heart of any public-private partnership, and stormwater is the next frontier,” Bryant said. “Municipalities and states are begging for private capital to be brought to the table to help narrow the funding gap. The public-private partnership approach might not close the funding gap, but it can certainly help to narrow it.”

Public-private partnerships have also been successful in Northwestern’s backyard of Chicago, Illinois. David St. Pierre, Executive Director of the Metropolitan Water Reclamation District of Greater Chicago explained: “The nice thing about private sector programs is that they allow the public sector to cost share with each community… Public-private partnerships really make the investment a possibility. They actually solve some huge problems in the Chicago region that people thought couldn’t be solved in 100 years. And I now believe many can be solved in a 5-10 year timeframe.”

Engaging with the Community

Stormwater runoff and infrastructure improvements often affect neighborhoods, businesses, and communities in a noticeable way. This reality provides opportunities, as well as challenges, for those seeking to implement change.

St. Pierre described the obstacles his organization faces: “When I think about an urban space like Chicago, one of the most difficult challenges you face is people. At this summit, we talk all about engineering and what green infrastructure can do. But a lot of what you have to overcome in an urban environment is how people think about water.”

“Some people say they don’t want green infrastructure projects because they think it will mess up the aesthetics of the community,” explained Korey Gray, Business Development Officer of DC Water, a water utility in the Washington, DC area. “At DC Water, we’ve got engineers who can tell you the best way to do things. But the bigger part is connecting with the public and getting them to buy into what we’re trying to do—be it local ratepayers, local government, federal government, or regional partners. Having everyone at the table and getting that initial buy-in makes the program that much stronger.”

In addition to involving community members in the decision-making process, expert panelists and policymakers stressed the need to bring demonstrable value to communities through stormwater development. “People will accept paying a higher water bill if they know they’re getting something in return,” Gray said. “That’s why we better be prepared to give local residents employment opportunities. We better be prepared to give an opportunity to local businesses to work with us on these projects to spur economic growth.”

St. Pierre described the value that Space to Grow, a program that converts Chicago schoolyards into vibrant outdoor spaces that incorporate green infrastructure, has brought to communities. “We take asphalt campuses, and we turn them into stormwater amenities that provide tremendous benefits to these neighborhoods. Now you have a community that takes ownership of those properties. It brings those communities back to life and also serves as an education center that gets people to think about water differently… You can use water to really create community,” St. Pierre said. 

 A New Direction for the Industry

Stormwater management impacts public health, employment, the wellbeing of the environment, and the vibrancy of our neighborhoods and communities. As policymakers and thought leaders discern creative solutions amid an uncertain future, new opportunities for community engagement are emerging. “Our industry is moving towards becoming real environmental protectors,” said Neukrug, former CEO of Philadelphia Water. “We’re looking in a new direction.”


The Water Environment Federation (WEF) is a not-for-profit technical and educational organization of 33,000 individual members and 75 affiliated Member Associations representing water quality professionals around the world. Since 1928, WEF and its members have protected public health and the environment. As a global water sector leader, WEF’s mission is to connect water professionals; enrich the expertise of water professionals; increase the awareness of the impact and value of water; and provide a platform for water sector innovation.

Photo credit: Minnesota Pollution Control Agency