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Friends of the Waters: The Ripple Effect

Originally published: 
April, 2017

In the late '90s, a friendship emerged between two students that continues to benefit regional waterways in Michigan and Wisconsin. Since their grad school days at SEAS, Elizabeth (Worzalla) Riggs (MS, ’99) and Cheryl Nenn (MS, ’99) have shared insights, resources, and advice to support each other’s conservation efforts.

As an example of networking, their story is excellent. But for these two friends of the waters, it may be nothing less than the “ripple effect” of alumnae helping each other.


Elizabeth Riggs, MS '99

Shortly after earning her master’s at SEAS, Riggs joined the Huron River Watershed Council (HRWC) in Ann Arbor, where she currently works with three other SEAS alumni, including Executive Director Laura Rubin (MS, ’95).

As HRWC Deputy Director, Riggs manages RiverUp!, a public-private revitalization of the Huron River focused on projects and partnerships that improve river ecology, recreation access, and placemaking initiatives, including the Huron River National Water Trail. Riggs notes that as plans for the water trail were getting underway in 2011, she reached out to Nenn—who was involved in the development of the Milwaukee Urban Water Trail in 2006. 



Cheryl Nenn, MS '99

 Navigating the currents of her own career through the Peace Corps, US Forest Service, and a stint as a Forest Restoration Project Manager for the City of New York, Nenn says she “finally landed” at Milwaukee Riverkeeper in 2003, a fact that delights Riggs, a Milwaukee native. As Riverkeeper, Nenn’s job is to identify sources of pollution to Milwaukee’s waterways, respond to citizen concerns, and to work with a variety of partners to find solutions.

“There’s always going to be a need for advocates to protect waterways because pressure on the polluters is weak to non-existent,” Nenn adds, “We really need people to be voices for the rivers.”

For her outstanding work as one of those “voices for the rivers,” Milwaukee’s Mayor Tom Barrett proclaimed March 24, 2017 as “Cheryl Nenn Day” during the city’s Water Week.



Clearing the waters

In the past few years, Nenn and Riggs each tackled the issue of coal tar sealant—a substance used to seal cracks in asphalt, and is also sprayed to form a protective layer on large expanses such as parking lots and playgrounds.

Riggs explains that the problem with the sealants—made from byproducts of the oil and gas production process—is that they contain high levels of polycyclic aromatic hydrocarbons (PAHs), known human carcinogens that are also toxic to fish and other aquatic life. PAHs from the sealant are released into the air through volatilization, while run-off moves loose particles into soils, storm-water catch basins, streams, lakes, and rivers.

“The issue was under our radar until we were approached by one of the Great Lakes groups,” says Riggs, “They asked us to promote community awareness about the issue, but as a science-based organization, we needed evidence that this problem was impacting the Huron River watershed.”

Over the next two years, HRWC monitored the levels of PAHs in its waterways, and collected information from the U.S. Geological Survey (USGS), the lead agency studying the issue.

“We came to see that coal tar sealants were a big problem,” says Riggs, “and that beyond the community education we could do, there was also a policy aspect to it, so we began advocating for a ban with our local units of government.” Riggs notes that U-M was “ahead of the game” in using alternative sealants on its campuses a number of years before.

Despite pushback from the sealant industry—whose representatives flew in to attend committee meetings—the City of Ann Arbor passed an ordinance banning the use of High-PAH sealants, including coal tar, in June 2016. “We’re on the radar nationally with groups like Coal Tar Free America,” says Riggs.

Riggs shared HRWC’s research and strategies with Nenn, whose organization was working on a similar ban. Though they also faced lobbying attempts to thwart the amendment, the City of Milwaukee banned the sale and use of coal tar sealants with high levels of PAHs in February 2017.

On the day the amendment was approved, Nenn was quick to email Riggs with the news. She wrote: “Despite a last minute attempt from the industry, we got this passed today! Props to A2 for being a good role model! Go Blue!”

Riggs notes that complete bans on sealants with high PAH levels, including coal tar, are gaining traction nationwide, adding that Austin, Texas was the first jurisdiction in the US to prohibit use of the substance in 2006. 


Where the waters meet: science, communication, and policy

Though proposed budget cuts to the EPA foretells rough seas for environmentalists, they hope that progress on a local scale—such as the achievements of Riggs and Nenn—may one day turn the tide. 

“We need to work with our cities, villages, townships, and counties to educate and encourage people to do something differently,” says Riggs, “The bottom line is that we should not take our environmental protections for granted, nor take our point of view for granted. We must look at the evidence-based science, and communicate it clearly and in meaningful ways to people who aren't actively involved in the cause.” 

Riggs recently brought that message further afield. Eager to discuss issues of importance to Michigan, Riggs joined conservationists from across the nation at the Clean Water Network’s “Fly In” March 2017 event in Washington, D.C.—where they met with senior officials in the EPA and Army Corps of Engineers. 

Nenn agrees that communication, both locally and nationally, is key in shifting hearts and minds—as well as policy. 

“I find myself going to a lot more common council meetings, community meetings, public hearings, and legislative hearings then I ever thought I would,” says Nenn, “I’ve had to become good at talking with the press and lobbying for good policy, while at the same time trying to stay on top of emerging science. 

“One of the things that I have really appreciated from my SEAS education,” Nenn adds, “is the diversity of training that we received. Even though I concentrated in natural resource ecology and management, I use my policy and environmental law training on a weekly, if not daily, basis.” 

To that end, Nenn advises current science-focused students to take advantage of policy and law classes, and conversely, that “policy wonks” make sure they have a solid understanding of the science. 

Another piece of advice surfaces from the success stories of Riggs and Nenn: Keep your networks strong, and your friendships flowing. 

Learn more about the projects and initiatives of the Huron River Watershed Council and Milwaukee Riverkeeper.