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Planes, Trains, and Bicycles

More than a recreational venue, the BWI Trail circles Baltimore-Washington International Airport to link neighborhoods, communities, and several modes of transportation

After motoring south on I-83 into Baltimore, I exited at North Avenue just north of downtown to catch the city’s light rail system. Carrying my bike, I hopped on the articulated trolley powered from overhead lines. We cruised down the middle of streets in urban neighborhoods and then through downtown, with the Inner Harbor on one side and Camden Yards and M&T Bank Stadium on the other. Then the train traversed through suburban areas, after which I got off at the BWI Business District Station at Baltimore-Washington International (BWI) Airport and found my way to the BWI Trail across the road.

This is what I came for. I took the train to an airport to experience the full extent of a novel intermodal transportation network highlighted by a trail looping around the airport. I would cycle the BWI Trail not only to see its engineering features but to take in some scenery and get a workout as well.

The 12.5-mile-long BWI Trail gives BWI Airport the distinction as the only major commercial airport in the country with a trail encircling its property. It connects bicyclists, walkers, and runners to community resources, public transportation, and area neighborhoods and businesses. The trail links five modes of transportation: rail, light rail, highways, aviation, and bicycle-pedestrian.

As the first transportation enhancement project to receive Federal Highway Administration funding under the Intermodal Surface Transportation Act of 1991, the trail has been built and maintained through a public-private cooperative effort. This includes the Anne Arundel County Department of Recreation and Parks, Maryland Aviation Administration, Maryland State Highway Administration, BWI Airport Neighbors Committee, Maryland Department of Natural Resources, and Mass Transit Administration.

It all originated when then-County Executive James Lighthizer and Director of Recreation and Parks Joe McCann of Anne Arundel County had a vision for community trails and greenways. In 1985, the county began a five-phase construction plan for a public path, and Lighthizer proposed the BWI Trail as part of his vision for a greenway network connecting nearby Annapolis to Baltimore. When he became Maryland’s secretary of transportation in 1991, he told his engineering staff at the Maryland Aviation Administration (MAA) to start work on the project.

But engineers at airports typically have more pressing issues than building narrow pathways for runners and cyclists. Not having experience with trails, MAA staff members contacted Dave Dionne, superintendent of the nearby Baltimore & Annapolis Trail, to learn about building a trail. “They originally were reluctant, but they quickly realized the trail would become a huge public relations benefit for the airport,” Dionne recalls. Airports have to deal with neighborhood issues like noise, stormwater runoff, and traffic, especially expanding ones in established neighborhoods, like BWI.

At the same time, in 1991, Lynn Bezilla, then-director of planning and environmental services for the MAA, stepped forward to spearhead development and construction of the trail. Bezilla recalls, “The first thing I did was to get a consultant who knew something about bike trails. I found Human & Rohde, who designed the Baltimore & Annapolis Trail. They worked the trail project with me from start to finish.” Based in Towson, Maryland, Human & Rohde is a landscape architecture firm specializing in reforestation, wetland delineation, and environmental work, in addition to trail design. “The next thing I did was to form a working group with the Maryland State Highway Administration (SHA) and the Anne Arundel County Department of Recreation and Parks.”

Unusual Cooperation
As owner and operator of BWI Airport, MAA had overall responsibility for the project and provided most of the land. SHA was responsible for the design, and the county was responsible for maintenance and operation once the trail was completed. As Bezilla reports, “All three agencies worked together through the process, and we all think this is one thing that made the BWI Trail project noteworthy; two state agencies and a county agency actually cooperated and got something done!”

In the beginning, Bezilla says, “I wasn’t thrilled when I was given this project to say the least. My job was building runways and terminals, not bike trails. However, I now look back on it as one of the most rewarding projects I ever worked on. The community loves it and uses it intensively.” He has since moved on and now serves as a senior associate of airport planning and development for KCI Technologies, an engineering firm headquartered in Hunt Valley, Maryland.

As associate landscape architect at Human & Rohde, Sally Malena headed the actual design of the trail. For the first step, Malena says, “We started looking at what land was in public ownership and then started walking around the airport and trying to find the best alignment, staying on public land.” MAA already owned most of the land around the airport, and SHA owned some as well. Anne Arundel County park land fell within it, along with Baltimore Gas & Electric power lines. “Once we identified land we could possibly be on, then we mapped and walked what would be the most fun and interesting for somebody to walk or bike on.”

Engineers entered the picture at this point. “We walked the trail initially with the state highway administration engineers and showed where we wanted the alignment to go and how wide. We gave them the standards and parameters on trails,” Malena relates. She also imparted a mindset that differs from the usual engineering approach to transportation design. “We worked with the engineers to get them to appreciate the fact you don’t necessarily want to go from point A to B by the most direct route. We want to meander a little bit. It’s not a roadway. We want this to be a fun experience.”

In fleshing out the overall design of the trail, SHA handled most of the engineering work in-house. Steve Ches, a senior engineer in SHA’s Office of Highway Development in Baltimore, started working on the project in 1993 as project manager. As the civil engineer recalls, “I thought it would be like a break, but it wasn’t really. It was a challenging project.”

Ches explains, “The most challenging part we had was keeping it on MAA property while trying to maintain specific grades for bike trail systems to meet ADA (Americans With Disabilities Act) compliance and things like that.” They designed the paved surface to handle a loaded utility vehicle, like a pickup truck for maintenance purposes, and it consisted of six inches of graded aggregate base and two inches of hot mix asphalt. Ches adds, “I wasn’t used to working with hiking or biking trails. I was used to working on road design, anywhere from interstates to Maryland state routes. This didn’t require a high degree of engineering as far as a roadway project would, but it did require followthrough with the environmental constraints we had to deal with.”

Malena reveals, “We had to have water quality, so we provided bioretention facilities along the trail. We had some major bridges and a major ramp going over a bridge and then down to grade. Safety factors were a big consideration because you had these major roadways going into BWI, and how do you get people around those safely? Also, we had a lot of wetlands. We had to build a lot of boardwalks.” As I tooled along, I saw where the trail hugs roads occasionally, goes over several roads, and follows existing ones over several bridges, giving it a good variety from a cyclist’s perspective.

Bridging Major Roadways
SHA built three major structures to accommodate the trail, including bridges over I-195 and Aviation Boulevard on the north side of the airport and a ramp down from the existing Stoney Run Road bridge on the west side. SHA’s bridge design division handled these and hired two consulting engineering firms for the detailed design. Alli Chaharbaghi, a team leader and project engineer in SHA’s Baltimore office, and his fellow engineers worked with them to make sure the bridges met state and federal standards.

Johnson, Mirmiran & Thompson designed the Stoney Run bridge ramp, which ramped up from grade level to an existing bridge. Chaharbaghi, a civil engineer with a specialty in structural engineering, recalls, “That was pretty interesting because we had to cut a portion of that existing bridge to get the ramp bridge connected to it. We had to intersect the bridge right in the middle.”

Greiner Engineers (now URS-Greiner) designed the I-195 and Aviation Boulevard bridges as prefabricated concrete structures. Chaharbaghi says this was a new experience for his division. “Usually, we do steel bridges, but these were concrete beams.”

 

Structural work also included 11 boardwalks over wetlands and small streams. Ches says, “There were some major challenges to the boardwalks regarding the construction. We had to deal with side fencing for safety. We looked at several other trail systems to get some ideas, but these were uniquely designed.” SHA’s bridge division designed these also, working again with Greiner Engineers. This, too, provided a new experience for Chaharbaghi and his fellow engineers, he says, “We hardly do any kind of timber bridges around here. Wood is much cheaper than concrete. We didn’t want to use concrete for such small structures. We couldn’t fill the area because of the environmental impact, and we didn’t want to put foundations in there. We just drove timber piles so we didn’t disturb the ground.”

As for the bioretention facilities, Ches says, “We had to address stormwater, and we did that with filtration trenches.” These collect stormwater that runs off and filter it, allowing it to gradually seep into the groundwater. Along the trail, I spotted these occasional long, narrow rock piles paralleling the pathway just a few feet off it.

The first section of the BWI Trail, 4.4-miles long, opened in July 1994 on the east side of the airport. Phase Two opened in 1995 along the south side, and this includes the Thomas A. Dixon, Jr. Aircraft Observation Area with paved parking, a playground, restrooms, and bike racks. As I came through here, I stopped and watched a plane come in to land. Many families were playing and picnicking here, and it makes a popular starting point for bicycling and running the trail.

Natural Step to Come Full Circle
“It became so popular so quickly,” Dave Dionne says of the BWI Trail. Original plans called for it to extend just along the east side of the airport. “It became natural to go ahead and ring the airport, so you could see all the various runways that had nice views from the higher elevations. You could watch the life of the airport, planes coming and going and taking off. It’s really pretty fascinating.” In 1999, the BWI Trail was completed.

The BWI Trail makes roughly a square pattern around the airport, with a spur off the southeast corner going to the Cromwell Light Rail Station and a spur off the northeast corner to the Linthicum Light Rail Station. The Light Rail system connects the area with downtown Baltimore and suburbs north of it. A short spur off the northwest corner goes to the BWI Amtrak MARC Station -- MARC (Maryland Rail Commuter) runs trains between Washington, D.C.; Baltimore; Martinsburg, West Virginia; and Frederick and Perryville, Maryland.

The spur off the southeast corner also connects to the Baltimore & Annapolis Trail, a popular rails-to-trails conversion that connects Baltimore's southern suburbs with Annapolis. The 13.3-mile-long linear park links towns, schools, and shopping centers.

Using the intermodal connections, Dionne says visitors can fly into the airport and spend the day cycling, as the facility sports bike racks, lockers, and bike rentals at the general aviation airport. Bike lockers also await at each light rail station and the Amtrak/MARC station.

Not as many people use the BWI Trail for riding to transportation connections as officials had hoped, but something else has filled the void. More than 15,000 people work at the airport at places like Northrup Grumman, which has a huge radar production and testing complex there, and car rental companies and other airport support functions. Many employees bike to work or use the trail on their lunch hour.

Lynn Bezilla says besides providing the obvious recreational and transportation benefits, the trail has improved airport security as well. “Anne Arundel County Department of Recreation and Parks patrols the trail with regular officers, and they also have a trained volunteer force. The volunteers are radio-equipped and can call for an officer if they see anything fishy going on. And just having more people around discourages people who might be up to some mischief.”

Safety around the airport complex is also improved with the aircraft observation area. People typically stop in their cars around airports to watch aircraft land and take off anyway. Having a designated area for doing that keeps them off roads and prevents traffic problems.

With my trail tour complete, I later picked up the light rail train at the BWI Airport Station at the at the terminal for my trip home. It nearly filled as we went along and picked people up at the various stops. Judging by this turnout and the fact many people were using the trail, the multimodal transportation system works, with the BWI Trail connecting all the dots. And the engineers who designed it see the benefits as well and appreciate the trail. In summing up the experience, Alli Chaharbaghi says, “I really enjoyed it. It’s a nice trail, and I see a lot of people using it. That’s rewarding.”


For more information on the BWI Trail, visit www.bwiairport.com/around_town/the_bwitrail


Progressive Engineer
Editor: Tom Gibson
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