Feature Article - November 2019
Find a printable version here

A Path Toward Conservation

The Environmental Benefits of Trails & Greenways

By Chris Gelbach


While the economic and transportation benefits of trails and greenways are well-established, the ecological benefits can be great too. Making the most of these opportunities requires a focus on a wide range of environmental topics during trail planning, construction and ongoing maintenance.

Greenways Defined

To understand both the positive and negative environmental impacts of trails and greenways, it's important to understand the distinction between the two. "A greenway to me is really the corridor of land," said Chuck Flink, a landscape architect and president of Greenways Inc., a greenway and open space consulting firm based in Durham, N.C. "The corridor could be pretty wide or pretty skinny. It's the land and, in some cases, the water. The trail is the tread—the pathway that we use."

According to Flink, separating the two provides the opportunity to talk about the environmental impact of the pathway or tread. "To me, there's no negative impact of a greenway on the environment because the greenway is the environment," Flink said.

The environmental impact of the trail itself needs to be considered throughout the process. "On occasion, there are sensitive landscapes that need to go through environmental assessments," said Liz Thorstensen, vice president of trail development for the Rails-to-Trails Conservancy. "But I would say that on the whole, for the rail-trail movement and the rail-width trail movement, oftentimes those projects are cleaning up almost blighted space."

Trail Planning

That said, Flink sees some projects go to extraordinary lengths to disturb environmentally sensitive areas as little as possible. He noted the example of the Violet Crown Trail which runs through Austin, Texas, and that will ultimately be a 30-mile trail through Central Texas. During planning for that project, a team from the Ladybird Johnson Wildflower Center walked abreast along the proposed pathway to make sure the route didn't disrupt any environmentally sensitive areas.

In some areas, the trail itself may not be an issue, but the construction can be disruptive to local habitats. Flink noted the example of California condor nests in the wall of the South Rim of the Grand Canyon that prevented construction on the Grand Canyon Greenway trail during that nesting season.

According to Jeffrey Ciabotti, Mid-Atlantic deputy planning director and trails practice lead for Toole Design, a leading multimodal transportation design and planning firm, trail considerations in environmentally sensitive areas can also include things like lighting. "You want to make sure that you've got darkened areas for nocturnal animals and specialized lighting that orients down so you're not creating light pollution that disturbs local habitats," Ciabotti said.

Other considerations include designing trails in areas with sensitive vegetation to include barriers that protect the underbrush and discourage trail users from wandering off the path. "Making sure you understand that area of development is really the most important factor to consider when you're putting in a project like this," Ciabotti said. "Making sure that you're creating a buffer zone between the trail and the essential parts of the vulnerable area is one of the first things you should be looking at."

Carefully designed trail corridors can not only conserve existing habitats, but also improve them. Thorstensen mentioned the example of considering the loss of pollinators across the country and planting vegetation along the trail corridor that encourages pollinators.

One example of a greenway that goes far beyond this effort is the Prairie Corridor in the Lincoln, Neb., region. The project is both a tallgrass prairie restoration project that has preserved more than 5,000 acres of land so far for new prairie habitat, and the home of what will be a 14.5-mile trail that will connect to a larger 134-mile regional trail when complete.

Design elements like underpasses for small mammals and elevated boardwalks to preserve wetlands can also help alleviate habitat depletion. But the fact is that the land conservation and habitat preservation provided by trails can also be a boon for edge species such as deer, raccoons and rabbits. In fact, Flink noted that when Grand Forks, N.D., proposed a greenway for flood mitigation and recreation after a flood in 1997, it also planned for potential overpopulation of some of these species.

"A big concern they had was that edge species wildlife would take over if they didn't manage it," Flink said. "They actually have an edge species wildlife plan and work with those species of wildlife."

A Connection to Water

In that greenway and others, a growing understanding of the increasing threat of flooding is spurring attempts to combat it in communities nationwide through sustainable design—and greenways and trails are often part of the equation.

A prototypical example is the Lafitte Greenway in New Orleans, which was proposed after Hurricane Katrina. Its design includes elements to store and retain stormwater, decrease flooding, mitigate urban runoff to improve water quality, increase trees and vegetation, and build habitat for beneficial fish, amphibians and birds. "It's a good example of how a community learns from a disaster, and how a trail can be part of the solution through thoughtful design and green infrastructure," Ciabotti said.

Another example is a project in the planning stages that Ciabotti is involved with now in Virginia Beach, Va., that will convert an often-flooded golf course in the middle of the city into stormwater mitigation with a loop trail around it. "I think we're going to see more and more projects like that as water becomes an issue throughout the country."

At the same time, situating trails along river pathways remains a common, enduring and appealing approach. The Anacostia RiverWalk Trail, for instance, offers roughly 16 miles of separated, multiuse trails along or connecting to the Anacostia River in D.C. and Maryland, with eventual plans for the trail to extend roughly 25 miles.

Over time, efforts to improve water quality in the river have included restoring five streams that flow into the Anacostia, along with investment in a $2.7 billion sewer tunnel system and greening program. These and other efforts have helped turn the once heavily polluted river into one that is close to being fully fishable and swimmable, with improved water quality, wildlife repopulation and more accessible shorelines.

Green Commuting

Projects like the Anacostia RiverWalk Trail also provide tremendous new commuting opportunities to cyclists that can help combat global warming and improve air quality.

"If you can design trails with transportation in mind, you can significantly reduce the amount of traffic on the road in many cases and certainly improve air quality," Ciabotti said.

Maximizing the transportation potential of a trail can involve efforts to not only connect communities through low-stress car-free routes, but also connections with local schools, universities, parks and other key destinations.

One example achieving this is the Razorback Regional Greenway in Arkansas, a 36-mile shared-use trail that connects six downtowns, three hospitals, 23 schools, the University of Arkansas, several major corporate headquarters, arts venues, parks, shopping areas and more.

In creating the design, Flink noted that an overland route was required for one portion that turned a three-lane road into a two-lane road with a buffered bike lane. "We connected it to three public schools where everybody was driving their kids to school," he said. "Today, we have these walking school buses and kids are bicycling to school for the first time and it's quite a phenomenon … Parents now take turns walking 30, 40 students to and from class. It's really great."

Flink also noted that connecting schools and the communities they serve can have a particularly strong impact on air quality through mode shift away from an endless line of idling vehicles. "The worst air quality we find in communities is often around schools at drop-off and pick-up times," he said.

Environmental Education

Connecting schools in this manner through a trail also creates opportunities for outdoor education. It can also include amenities such as outdoor classrooms on trails such as the Razorback Regional Greenway and the Ann Springs Close Greenway in Fort Mills, S.C. At the latter, the local schools touch the greenway, and teachers regularly take students out to outdoor classrooms built into the greenway.

"They're like mini outdoor auditoriums," Flink said. "They have seating that's done in a very beautiful, tasteful, natural way. There's a focal point in the space where the teacher's going to be, and it allows them to have the eyes of the kids on them and they can conduct their class right there."

Some trails are providing both cultural and environmental opportunities to students and other users alike. The Indianapolis Cultural Trail includes five acres of garden beds in addition to 25,000 square feet of rain gardens adjacent to the trail that filter 4 million gallons of water a year and help protect the White River watershed. The project also features seven public art projects along the 8-mile path.

In Idaho, the Trail of the Coeur d'Alenes provides a solution to environmental problems created by the state's mining industry. The 73-mile asphalt trail and its gravel barriers help isolate the contaminants from mining, and today visitors can enjoy 20 developed trailheads, 17 scenic waysides with picnic tables and benches, and potential views of animals such as moose, osprey, eagles, herons, otters and beavers. It also serves as a living example of what is possible with environmental restoration, while reminding visitors of the challenges that remain.

"They've used it as a sort of an educational piece to get people to understand how the land got contaminated and what the process was for cleaning it up and maintaining it over time because it's a very visual real-world example of how that happens," Ciabotti said.

The Ecotourism Imperative

In addition to the environmental and educational benefits that it can provide, a smartly planned trail can also bring trail users closer to nature through a variety of ecotourism opportunities. According to Ciabotti, this can include elements such as incorporating birding, spur trails for hiking, fishing platforms, community gardening areas and more.

Austin's Violet Crown is an example of a trail that exploits several interesting natural attractions, following some of the most beloved areas of Barton Creek, including several swimming holes, climbing walls and trailheads. Once the full 30-mile trail is complete, it will stretch from Zilker Park (home of Barton Springs Pool and events such as the Austin City Limits Music Festival) through the Lady Bird Johnson Wildflower Center and into the rolling countryside of Hays County.

"Think about your project in the beginning and what type of other individual ecotourism benefits you could have," Ciabotti said. "There's reams of economic benefit studies we've got on thousands of trails throughout the U.S., and you can use the ecotourism dollars to help manage your corridor."

To seize the full potential of ecotourism, communities along the trail also must be ready to take care of ecotourism visitors with services such as lodging, bike rentals and restaurants. "They need to make sure that they're prepared to take care of the folks that are using it so that they'll come to their communities, spend some money … and capture the economic benefit as much as possible to help subsidize trail enhancements, amenities along the corridor, further trail development and ongoing trail maintenance," Ciabotti said.

In addition to these ecotourism opportunities, the growing focus on connections in trail networks is helping people use trails to access more natural spaces. The Virginia Creeper Trail provides a notable example given its location near the Appalachian Trail, the Jefferson and Cherokee National Forest and many other natural recreation areas. "The Virginia Creeper acts as a conduit for the public to access some of those areas, and they've done a really nice job with it," Ciabotti said.

The 34-mile trail gives people opportunities to bike, walk, horseback ride and cross-country ski, while meandering through open farmlands, forests, Christmas tree farms, streams, small towns, one of Virginia's largest trout streams and other scenic areas.

This kind of thoughtful design can make the most of local landscapes to create a vibrant experience for trail users. "I try to emphasize in the design variety, rhythm and syncopation," Flink said.

Flink recommends going out and really assessing the land with a focus not on being expedient in trail design, but instead with intentional thinking about the kind of experience you want people to have when they use the greenway. "What is the story you're trying to tell? What are the landscape features you're trying to highlight?" he said.

Making New Connections

In dense urban environments, there's often a balance to be realized between this impulse and the necessity to seize limited opportunities to create new trails and connections to existing networks. "It's more about being opportunistic about reutilizing all different kinds of rights of way in terms of rail-trails, power line corridors, stream corridors," Thorstensen said. "It's much more about how you can maximize connections in an ever-urbanizing world."

And in making those connections, it's also critical to make connections in terms of both public and private partnerships to support the ongoing maintenance and development of the trail—because it's not something that most parks departments can take on successfully alone.

"You're never going to have enough resources to do what you need to do in terms of keeping up with the demand for trails because that's going to just exponentially grow over time," Ciabotti said. "The more people use them, the more they're going to want more."

As massive trail networks continue to be built in urban areas—including examples such as the Circuit Trails in Philadelphia and BeltLine in Atlanta—these amenities will likely over time become more expected by younger workers.

And whether it's by creating newly restored natural areas out of brownfield sites or by connecting people to existing natural gems, these trails figure to play an important role in natural recreation and consciousness moving forward.

Even now, Ciabotti is seeing universal demand for environmental improvement in projects such as the current planning for the Joe Louis Greenway in Detroit, a proposed 31.5-mile trail looping around the city and including the Detroit Riverfront. Every community surveyed has made its priorities clear. "All across the board, these communities want this project to help them replant trees, to preserve green space, to give kids access to more green space and to help them make a connection to it that they currently don't have," Ciabotti said.

Through smart planning, design, implementation and maintenance, recreation managers can play a role in this effort. As communities seek connections with the environment, with other communities and with healthy recreational opportunities, trails provide one of the clearest paths to achieving those goals. RM