Roger Williams Park stormwater project a model for other communities

PROVIDENCE — A woman called Brian Byrnes the other day to compliment him on the new patio in Roger Williams Park where she had set up a table and chairs for a Friday food-truck night at the Carousel Village.

It took a minute for Byrnes, the deputy superintendent of the Providence Parks and Recreation Department, to realize that she was talking about the permeable pavers in one of the many new projects in the park designed to capture and filter contaminated stormwater.

“All she needed was a firepit,” Byrnes said with a laugh.

The woman, for good reason, mistook the water treatment project for a garden to lounge in and enjoy a meal. With its curving berms and native plants, it’s designed to look as natural as possible while still doing a critical job for the park.

The project next to Willow Lake and 41 others like it were built over the past two years as part of a larger effort to clean up the park’s waters. All of them adhere to a similar design philosophy that is becoming more common in public works projects across the nation. It embraces eco-friendly elements and frowns upon the use of concrete that is the hallmark of traditional stormwater infrastructure.

The work in Roger Williams Park is already attracting attention as a model for other communities. With the help of federal funds, the parks department has partnered with the Audubon Society of Rhode Island, The Nature Conservancy, the University of Rhode Island and the University of New Hampshire to turn it into a stormwater innovation center.

Roger Williams Park totals 435 acres but nearly a quarter of it is covered by water. Eight interconnected lakes make up 100 acres of the park. When he was asked why improving the water quality is so important, Byrnes talked about getting more people out kayaking on the lakes or fishing in the waters. They should not have to worry about toxic algae blooms or silted-up coves in a park that, he emphasized, was designed to be an oasis for the city’s residents.

“We want more people to be able to use it,” Byrnes said as he gave a tour of the stormwater projects on a recent morning.

The efforts have a larger impact, too. Controlling and treating stormwater is critical to everything from protecting precious drinking-water supplies around Rhode Island to keeping the state’s beloved beaches and commercially important shellfish beds open in the summer.

Stormwater is one of the biggest threats to water quality in bays, rivers and streams. When it runs off roads and other impermeable surfaces, it can carry oils, chemicals and heavy metals into waterways. And when it runs off lawns and gardens, it can pick up nutrients from fertilizers and animal waste and spur unwanted algae growth that can reduce dissolved oxygen levels in water and, in some cases, cause fish kills such as the infamous one in Greenwich Bay in 2003.

There is a growing urgency to tackle the problem because climate change is not only increasing the amount of rain that falls on Rhode Island on an annual basis but also ramping up the frequency of extreme precipitation events that can overwhelm decades-old catch basins and pipe systems designed to handle stormwater.

“These projects that help capture and filter stormwater and help reduce pollution ... are even more important now as we confront climate change,” said Janet Coit, director of the Rhode Island Department of Environmental Management.

The largest infrastructure scheme in Rhode Island history — the ongoing construction of tunnel networks under Providence and East Providence at a cost of $1.5 billion to store untreated stormwater and sewage during heavy rainfalls — is aimed at addressing the problem in the Providence River and Narragansett Bay.

But smaller projects that cost far less money and don’t require huge amounts of concrete also can be effective. Known as “green infrastructure,” they incorporate natural elements to collect stormwater, screen out sediments and then channel it to a place where the water and any contaminants can percolate harmlessly into the ground.

They include things like rain gardens that fill up with water during heavy rains and then eventually dry out, swales that direct water down a rocky path that allows it to filter underground or manmade pools that let water slowly flow out after contaminants and sediments settle.

Such projects aren’t uncommon in Rhode Island. There are a range of them at Providence College. A decade ago, the Rhode Island Public Transit Authority installed a permeable parking lot in Elmwood that was the largest in New England at the time. An artificial wetlands was built in Middletown to control runoff into Bailey Brook, which feeds into drinking water reservoirs for Aquidneck Island.

But the large number and variety in Roger Williams Park makes it ideal as a demonstration site, said Ryan Kopp, the inaugural coordinator of the stormwater innovation center. The park’s old Seal House, which has fallen into disuse, is set to be renovated as a place for school groups, planners and anyone else who’s interested to see real-time monitoring of the water quality in the park and learn about green infrastructure. Information signs have been set up around the park and “picture posts” were installed for people to shoot photos of the new projects during storms to show how they’re faring.

“Everybody is learning through this whole process here,” Kopp said during the tour with Byrnes.

Providence was required to make the improvements in Roger Williams Park because of a consent agreement it signed with the DEM in 2017. But Byrnes said the parks department had been working for years before the agreement to do what it could to clean up the waterways in Roger Williams Park.

The first major green infrastructure project in the park dates to the early 2000s with the closure of Roosevelt Road, the removal of much of the roadway and its transformation into a walking path flanked by rain gardens that leads to the Carousel Village and Japanese Garden. The parks department followed up in 2012 with a river-rock bioswale next to Polo Lake.

If anything, Byrnes said, the agreement with the DEM was welcomed by parks staff because it guaranteed a good chunk of money would be channeled into fixing the water-quality problems in the park. That has largely been the case. The city spent $1.5 million on all the projects in the park.

But more needs to be done to make deeper changes. The lakes in the park are part of a larger watershed that flows into the Pawtuxet River and on into Narragansett Bay. To the north of the park are Tongue, Spectacle and Mashapaug ponds, which are surrounded by development and whose waters are polluted. The ponds are all connected and, from Mashapaug, eventually empty into the park through a pipe under Route 95 that follows the historic course of a bygone stream.

“These impaired waterways here are being fed by those impaired waterways,” Byrnes said.

So taking care of the sources of contamination in the park can only go so far. The city is in talks with the state Department of Transportation, which owns the outlet pipe from Mashapaug Pond, to build a filtration system that would address the contamination coming from outside the park.

Providence Mayor Jorge Elorza looks at the ongoing improvements in Roger Williams Park through a social-equity lens. For the people of South Providence, the park may be their only access to green space in the city. The same can be said for other parks elsewhere in the city.

“As a matter of racial justice and social justice, this is a priority for us,” he said. “To many of our residents, the parks are their backyards.”