Posts about Greenbelt

The problem: the county can't simultaneously develop 27 centers

One issue is that the current vision is too broad. The 2002 General Plan designates 27 growth centers. 15 are at each of the county's Metro stations, and another 3 are at the Bowie, Seabrook and Riverdale MARC stations. 9 other centers are far from existing or planned rail transit, in places like National Harbor, Konterra and Westphalia.

This isn't serving the county well, says M-NCPPC planner-coordinator Sonja Ewing. Virtually all of the centers remain undeveloped, and none have reached their housing and employment density targets.

Each center fits into one of 3 vague categories, "Metropolitan," "Regional," and "Community," but those often lead to competing and disjointed planning efforts. This time around, M-NCPPC proposes to adopt a more descriptive system with 8 categories. Each one comes with its own particular desired land use mix, desired types of housing, height limits, maximum floor-area ratios, and density limits.

M-NCPPC will also designate 2 or 3 of the "urban center" locations as "Priority Improvement Districts" (PIDs), where the county would provide marketing, infrastructure investments and financial incentives to encourage private development.

Planners pick 3 "high performers" and 3 "game changers"

After analyzing and scoring all 27 areas, Planners chose 6 potential downtown sites, all of which are at Metro stations. They say 3 of them, Prince George's Plaza, College Park, and New Carrollton, are "high performers" best poised for the PID designation because of the existing level of activity there.

The other 3, which they dubbed "game changers," need an additional push to make them viable downtowns. These sites are Greenbelt, which could be the FBI's future home, Largo Town Center, where the county wants to see a regional medical center, and Branch Avenue, where WMATA has expressed interest in a public-private partnership to build around the station.

The audience appeared to favor College Park as the best "high performer" due to the presence of the University of Maryland. There was also clear consensus that New Carrollton made sense as a downtown since it is already a major regional multimodal transportation hub. Largo Town Center was the most-favored "game changer" location.

I left the town hall meeting with several questions, which I hope can receive some attention as we move through the Plan Prince George's 2035 process. In the next part, I'll look at those questions.

Before the roundabout was built on Cherrywood Lane, there wasn't even a stop sign, so anyone leaving the Metro had to wait for an opening in traffic. This led to significant backups of almost a half-mile, especially in the evening rush hour. Since the roundabout opened, I've never experienced a backup of more than 5 cars.

One of the tradeoffs, though, is that the roundabout required losing a section of the bike lanes on Cherrywood Lane, a key part of Greenbelt's bike network. Westbound cyclists are headed downhill, so it's fairly easy to merge into traffic. But eastbound cyclists are climbing a hill, and it can be daunting to merge into the faster traffic.

That's where one of Greenbelt's innovations comes in: a bypass. Where the bike lane ends before the roundabout, cyclists ascend a ramp to a widened sidewalk, then return to the bike lane on the other side.

Unfortunately, the bypass isn't well marked and is easy to miss. Cyclists headed to the Metro should merge into traffic instead, but that's not clear when the bypass begins due to a lack of signage at the decision point.

As the bike lane narrows, a sign directs cyclists to move onto the sidewalk, though it seems like it's really meant for drivers. A pavement marking or even a sign that says "use path" with an upward right arrow, like this one in Atlanta, would be clearer.

Another problem is that pedestrians don't realize that the sidewalk here doubles as a bikeway. Not expecting to see cyclists passing them, they walk in the middle, creating an opportunity for collisions.

Some paint could help this situation as well. In Atlanta, the city striped a bikeway on a short segment of sidewalk to direct bicyclists away from a short gap in the 5th Street bike lane.

For westbound cyclists, there is no bypass. The bike lane abruptly ends at a concrete splitter island, and riders are expected to merge into the car lane to go through the roundabout. The city did install an orange flexpost to improve visibility, but there's no direction for cyclists or drivers, creating a safety hazard.

While there are raised crosswalks on the western and northern sides of the roundabout, improving pedestrian safety and slowing traffic, the city didn't build one on the eastern leg. Drivers won't slow down, making it harder for cyclists to merge into traffic. On top of that, the lack of a crosswalk means cyclists using the bypass have one fewer crossing to the Metro.

Even without the changes I'm suggesting, the roundabout is a huge improvement over the previous intersection. Greenbelt's staff should be commended for designing fixes for the intersection. But this great project could be even better.

The Planning Department says that they will study the roundabout to determine whether further changes are necessary. Hopefully, some of these improvements will make the cut.

Purple Line open houses: The Maryland MTA is holding 5 open houses to inform residents about the Purple Line, now looking a lot more likely to actually become a reality. They're tonight (Tuesday) in Silver Spring, Thursday 5/9 in Riverdale, Saturday 5/11 in Langley Park, Tuesday 5/14 in Bethesda, and Wednesday 5/15 at Woodridge Elementary School in Hyattsville. Each is 5-8 pm, except the Saturday one which is 11-2.

Bike to school: If you have children in school and don't bike to school regularly, tomorrow is a great time to try. 17 DC schools are participating, and for the dozen on those which are on Capitol Hill, families can congregate in Lincoln Park for an event featuring Ray LaHood, then form bike trains to the schools. Sandra Moscoso has more on Greater Greater Education.

Walk Route 1: CSG's next walking tour looks at Route 1 in Fairfax, the oft-forgotten highway where big box sprawl has the potential to become eco-friendly, walkable communities. Volunteers will help groups take the bus from Huntington Metro for those arriving by transit. RSVP before it's full!

Height "master plan" meetings: The National Capital Planning Commission and DC Office of Planning are working together on a study that might recommend changes to the federal height limit, or might not. Regardless, the issue is sure to be completely noncontroversial, since as we know nobody ever wants to argue about the height limit. (Kidding.) The first public involvement is next week, with a meeting Monday, May 13, 6:30-8:30 pm at the Petworth Library, and then Saturday, May 18, 10:30-12:30 at the MLK Library by Gallery Place Metro.

Learn about, push for BRT: There's a big hearing on Montgomery County's BRT plans on Thursday, May 16, 6-9 pm in Silver Spring. Can you testify? Also, Montgomery transportation planner Larry Cole will talk about BRT as well as MARC expansion at ACT's monthly meeting Tuesday, May 14, 7:30 pm in Silver Spring.

What's up with Pennsylvania and Potomac? The second public meeting on the intersection at Potomac Avenue Metro is Thursday, May 16, 6:30-8:30 pm at Payne Elementary. Have DDOT and its consultants listened made the early designs even better to walk and bike, or have they gotten worse? We'll find out!

Bike to work: Just a little over a week after Bike to School Day (but much farther down our chronological calendar) is Bike to Work Day on Friday, May 17. Pledge to ride, stop by one of the pit stops around the region, join one of the commuter convoys along popular routes, and support almost all of the event sponsors.

Talk Smart Growth with David Grosso: Ward 3 Vision, the smart growth resident group in upper Northwest DC, is having a meet and greet on Tuesday, May 21, 6:30 pm at Guapo's by the Tenleytown Metro. At-large councilmember David Grosso will be there to hear from you about your vision for a more walkable and vibrant Ward 3 and all of DC.

Roosevelt Ride: Ride around Greenbelt, the New Deal planned community, in your best New Deal-era attire, followed by a picnic. You can also get a free tour of the Greenbelt Museum, which shows how families lived in what was built as working-class housing in 1937. That's Sunday, May 26; the ride starts at 11, the picnic after, and the tours at 1.

Have an event we should consider including on the ? Send them to events@ggwash.org. Please include a URL to a webpage that has the information about your event as well, so that we can link directly to your event.

We received an email from the PR firm Edelman about a new website they are launching on behalf of Walton. The site, called "A Welcome Home for the FBI," argues that "Westphalia Town Center would provide a secure, state-of-the-art campus for the FBI within a vibrant community where FBI employees and their families can live, work and play," and that "Westphalia Town Center would be a win-win-win for FBI employees and their families, as well as Prince George's County residents and businesses."

There's even a map, captioned, "Westphalia Town Center provides many convenient transportation options." Does it, now?

While Westphalia is located next to the Capital Beltway and Pennsylvania Avenue and adjacent to Joint Base Andrews, it's not on or near a Metro line, MARC train, or the planned Purple Line. I've placed a star around potential spots for the FBI that are on Metro: Greenbelt, Franconia-Springfield (Fairfax's proposal), and two suggestions from Greater Greater Washington contributors, Morgan Boulevard and Suitland.

(This map actually shows Metro in entirely the wrong place. Notice how the Orange and Blue Lines appear under the Potomac around where Smithsonian station would be. The Red Line crosses into Maryland east of DC's the northern point, not west. This map doesn't show the Blue Line out to the Beltway at all, and the southern Green Line actually runs along Suitland Parkway.

It clearly looks as though this map originally had no Metro at all, and the designers hastily slapped the Metro lines on without sizing and positioning them right. Perhaps this illustrates how much Westphalia really thinks about transit.)

Walton is so eager for the FBI that they recently offered to fund a bus line to Branch Avenue Metro. Unfortunately, a bus is unlikely to draw nearly the percentage of FBI workers that a Metro site would. The county has explored ways to extend the Green Line to Westphalia, but no serious planning has been done for it and nobody, including Walton, has any idea of how to pay for it.

As a greenfield, largely undeveloped site, Westphalia will require lots of new, expensive infrastructure whose long-term costs will get pushed onto the public. That spending will ultimately weaken pressure to build in existing communities where there's already underused transportation infrastructure, at the Metro stations. Those communities, however, don't have PR firms to push the government to put jobs there.

Putting the FBI in Prince George's County is the right move. The east side of the region has not gotten its share of federal or private jobs, forcing people to travel long distances from east to west. The FBI wants a large security fortress, which is incompatible with potential locations in central DC.

An site that is short walk from one of Prince George's 15 Metro stations, however, could house a large high-security complex and also catalyze walkable transit-oriented development closer to the station. This would maximize the value we get from our existing regional transportation network. With so many available Metro-accessible sites in Prince George's, Westphalia is not a good spot for the FBI.

Ivy Lane is a short street between Kenilworth Avenue and Cherrywood Lane, near the Greenbelt Metro station. It passes through a suburban office park, but because it connects Old Greenbelt with the Metro and Greenbelt West, it is very popular with cyclists.

As I crested the hill on Ivy, I began to pick up speed. About this time, a platoon of cars released by the light at Kenilworth Avenue began to pass me. Most gave me a wide berth, moving into the left-turn lane to pass me, even though I was in the bike lane.

The first of the cars in this platoon was a silver sedan, and as we approached the entrance to 6404/6406 Ivy Lane, the car signaled and turned right without first moving into the bike lane. That car was about 2 car-lengths ahead of me when the driver turned. The second car continued straight ahead.

Then the third car, a maroon Ford Explorer, began to pass me. As the rear wheel was even with my handlebars, the driver initiated her right turn into 6404/6406. I jammed on the brakes, and swerved toward the curb. I missed colliding with her vehicle by less than 6 inches.

As it happened, the security guard who patrols this office park was waiting to turn out of the same driveway. As I was avoiding the collision, I yelled loudly, and having witnessed the near miss and hearing me yell, the guard quickly turned around and went after the motorist. I followed.

When I caught up to the guard, he had flagged down the driver and was talking to her. As I biked up, I heard her say, "I didn't hit him." I responded, "You only missed me by about 6 inches."

Her response stunned me, and probably goes a long way to describing the plight of cyclists in this country. She said to the guard and me:

I had my signal on. You were supposed to stop for me.

In the first place, this is completely inaccurate. When driving on a street with bike lanes, the bike lane is considered a regular lane. You always have to yield to cyclists in the bike lane if you need to turn across it.

And the appropriate maneuver is to first merge into the bike lane before turning right. In this case, she should have merged behind me, since she did not have room to pass first.

In the second place, because she initiated the turn before she passed me, I really had no way of knowing that her signal was on anyway. Yes, cars have signals on the front, too. But as the front of her car passed me, I was focused on watching the car in front of her, because I did want to be right hooked by that driver either.

The woman told the security guard, "I really need to go. I don't have time for this." And I said, "I'm happy to let you go, but first I want to make sure you understand what you did wrong. You could have seriously injured me or killed me."

I explained that she should have moved into the bike lane first. I also said that if she didn't believe me, that she should look up the law for herself.

She said "sorry." (By her tone, she clearly wasn't).

I told her that I didn't want her to be sorry. I wanted her to not do this again.

At this point, we both went on our ways. But I thought about the experience for the rest of my ride.

I wondered whether I should have acted differently following the near-miss. I did not call the police. I assumed (perhaps incorrectly) that since there was no contact, they wouldn't consider it worthy of followup. But a friend of mine who has had experiences like this in Greenbelt says that the GPD will follow up to educate a driver if a cyclist or pedestrian reports a tag number after an infraction.

It's clear that the Maryland Motor Vehicle Administration doesn't do enough to educate new drivers about how to interact with cyclists.

But the State Highway Administration and local jurisdictions could also do more. The woman who almost hit me was probably in her late-40s. No amount of improvement to the driving test would have captured her.

In my experience biking in this section of Greenbelt, the right hook is probably the most common issue.

It seems that drivers need to be better educated about how they're supposed to behave around cyclists. The Manual on Uniform Traffic Control Devices does include sign R4-4, which applies when a right turn lane is present to the right of the bike lane.

But the MUTCD does not seem to include any signage for when there is no right turn lane. I created a modified version of the R4-4, which could serve in situations like this. But it will likely take a while for anything new to make it into the MUTCD.

Local jurisdictions, though, could have a freer hand in situations like this. Ivy Lane, after all, is a Greenbelt city street.

The Greenbelt Police Department does have a history of doing targeted driver education and enforcement, so that's another way the city could work toward resolving the issue.

Sunnyside Avenue is a short street connecting Route 1 in the west with Edmonston Road (the northern extension of Kenilworth Avenue) in the east. Between Route 1 and the CSX railroad tracks, the road is 4 lanes wide. East of the tracks, though, the road narrows to 2 lanes and crosses the undeveloped Beltsville Agricultural Research Center.

The road crosses Indian Creek on a bridge that is only 2 lanes wide, and which does not have room for sidewalks or bike lanes. Additionally, its height is actually below the 2-year flood level, which means it's frequently closed by high water.

The $13.5 million project will reconfigure Sunnyside all the way from the railroad tracks to Edmonston Road. It will raise and lengthen the bridge so that it is clear of the 50-year flood level. It will also add bike lanes and sidewalks between Edmonston Road and the tracks.

The county should be commended for including bike and pedestrian infrastructure in this project. It's refreshing to see that Prince George's does seem to be serious about allocating road space to users other than just motorists.

But in a somewhat troubling development, the reconstruction includes full-width shoulders to the entire length of the project. This means the roadway will be 4 lanes wide, although initially, at least, the road will only be striped for 2 lanes.

If the county decides to widen Sunnyside to 4 lanes, after this project all it will take is some repainting. In fact, the county could decide to just stripe the bridge for 4 lanes during construction if they wanted.

But according to Susan Hubbard, a PIO with the county's Department of Public Works and Transportation, the county doesn't plan to make the road 4 lanes wide. It's not going to be built to 4 lanes, and it's not going to be widened to 4-lanes. Based on the email exchange I had with Ms. Hubbard, it doesn't even sound like anyone in the department has even considered widening the road. One wonders if she doth protest too much.

It's quite strange that the county is making the road so wide, but doesn't seem to even be willing to admit that they might want to use the shoulders for lanes in the future. Perhaps they're afraid doing so will bring out opposition.

But it will be so easy to widen the road in the future, since it will only take line paint and a few hours. If the county wants to "widen" the road in the future, will they even need to ask the community?

Why widen?

According to Hubbard, the road needs to be so wide because of the construction phasing. First, the county will construct a new 2-lane bridge north of the existing bridge, and move the cars there. Then the county will tear out the old bridge, and widen the northern span to take up the space where the current bridge is.

It's not clear why Prince George's thinks all this extra concrete is necessary in the end. Hubbard claims that reducing the width of the bridge won't reduce the cost, however. Besides, she says, the county has already spent the money to design this concept, and it will cost money to redesign the bridge (eating up the savings).

The area between the railroad and Edmonston Road is not going to develop. The land is owned by the Department of Agriculture and is environmentally sensitive. Additionally, while Maryland hopes to widen 2-lane Edmonston Road, that project has no funding and many in the area oppose it.

While Hubbard contends that 2 lanes of concrete will cost the same as 4 lanes of it, I'm not sure that argument holds water.

I'd much rather see the money for the 2 additional lanes across the bridge be spent completing the sidewalks on the western section, or on any number of other bicycle, pedestrian, or transit projects in the county.

Regardless, if the county rebuilds Sunnyside Avenue as planned, with 2 extra (unused) lanes, it will surely be tempting for engineers in the future to widen. It would be great if the county would make assurances that such a widening will not happen without a public process.

One of the targets for redevelopment in this area is the Greenbelt Metro station site. Currently a sea of almost 4,000 parking spaces, it's a prime site for transit-oriented, mixed-use development. The transit hub is home not only to the Metro, but also to MARC trains and several bus lines. The plan also leaves open the possibility for the site to develop for a GSA tenant like the FBI.

The plan also targets Beltway Plaza and the Greenway Shopping Center for redevelopment. Both of these auto-oriented retail centers are along Greenbelt Road, a major suburban arterial corridor. This wide roadway forms a barrier separating neighborhoods.

The plan notes that major roadways like Greenbelt Road have created "significant barriers to connectivity and pedestrian and bicycle safety, effectively separating the sector plan area into isolated sections." Greenbelt has been split into several pods over the years by freeways like the Capital Beltway, the Baltimore-Washington Parkway, and Kenilworth Avenue, and citizens spoke out about the divisions these roadways have created.

As a result, the plan seeks to address the problems created by decades of investment in auto infrastructure and years of underinvestment in alternative modes.

"The sector plan area is characterized by major highway intersections and freeway interchanges that directly and negatively impact pedestrian and bicycle mobility and access."

The plan proposes to transform the area to "maximize pedestrian and bicycle accessibility, mobility, and safety." It calls for completing a continuous network of sidewalks, bikeways, and trails; for reconfiguring Greenbelt Road to include dedicated bike facilities and wide sidewalks; for coordinating transit services to increase ridership; and to enhance safety for all users.

All of those improvements are terrific ideas, and they've been needed for years. Unfortunately, it sounds like the plan isn't really serious about these improvements.

Plan counteracts its own solutions

Seeming to have forgotten about all the problems created by bigger and wider roads, the plan calls for widening several arteries in the sector plan area. Most notably, the plan calls for adding a lane in each direction to Greenbelt Road in front of Beltway Plaza and Greenway Center. It supports widening Kenilworth Avenue and the Capital Beltway. The county also proposes widening a 2-lane section of Hanover Parkway to 4 lanes.

The plan still includes a proposal to spend several million dollars reconfiguring the Greenbelt Road/Kenilworth Avenue interchange into a "diverging diamond," which will be even less friendly for non-motorized users.

It's especially ironic that these elements are in the plan, since at the community meetings planners talked about the exact opposite: road diets.

And in this case, road diets are probably warranted. A traffic study conducted as part of the planning process found that none of the roadways in the sector plan area was failing. Neither were any of the intersections.

So, despite a lack of congestion; despite talk of road diets; despite wanting to increase walking and bicycling; despite all of that, the plan still calls for widening roads.

It's almost as if, having decried the unintended consequences of the transportation policies of 1975, the plan says: there's nothing wrong with solving those problems with the same solutions.

Widenings confound positive changes

What's most baffling about these highway widenings is that they'll not only counteract the solutions proposed make walking a true option in this corridor, but they'll also make the mixed-use vision less likely to come to fruition.

A walkable node at Beltway Plaza is all well and good. But how well will it be connected to Berwyn Heights on the south if it's separated by a 10-lane road? Putting bike lanes on Greenbelt Road sounds nice. But how safe will it be to bike alongside 10 lanes of traffic? Completing the sidewalk network is long overdue. But how pleasant will it be to walk alongside one of the widest arterials in the region?

Speeding trips through Greenbelt will also encourage more suburbanization in the less-developed sections of the county. That will take office and retail demand away from the parts of the county where the infrastructure already exists to serve it.

No, the plan will not enable the future it envisions, because it still clings to the infrastructure changes that created the divided, pedestrian-hostile environment it seeks to fix.

It's not too late for Prince George's to build the foundation for a more walkable and sustainable Greenbelt. But the Planning Board and County Council need to urge changes to the plan. Without the uncalled-for widening of the roadways in the area, the plan has a chance of creating the mixed-use nodes and increasing walking, biking, and transit use in the planning area.

The Prince George's County Planning Board and County Council will be holding a joint session public hearing at 7 pm Tuesday in Upper Marlboro. If you're a resident of Prince George's, write the Council or come to testify. Tell them that positive change requires taking a different approach than ones past.

The Greenbelt Metro station is a suburban park and ride. On the east side of the station, where the bus bays are located, is a large surface parking lot. With about 4,000 spaces, the sea of asphalt extends over a quarter-mile from the station entrance.

Behind the bus bays, a gentle, largely treeless slope leads up to the off-ramp from the Beltway into the station's parking lot.

What this means is that the people waiting on their bus to come in have absolutely no shade. I don't know if the mass of asphalt in the parking lot magnifies the heat or not, but the direct sunlight is bad enough on its own.

In the morning, riders cluster behind the small bus shelters. The thin layer of plexiglass is all the protection these riders can get. In the afternoon, riders can at least sit inside the shelters, though the protection is still thin and the shelter keeps out the breeze.

The nearest place riders can get any shade is in the station's mezzanine. And since it's quite a walk to get to the farther bays, it's not an option for most riders to wait there.

This is not just about rider comfort. It's about safety. On hot summer days, it's only a matter of time until someone faints from heat exhaustion or heat stroke while waiting on the bus.

WMATA or Prince George's County should consider taking steps to create some shade at the station. For the evening rush, that could be in the form of planting some trees on the slope behind the bus bays. The transit agency could also replace the transparent roofs on the bus shelters with opaque ones which would provide more shade.

Another approach could be similar to Phoenix's. In the southwestern climate there, shade is far more important than rain protection. Stations on their new light rail line are primarily designed to shade waiting patrons. WMATA could also install shelters designed to shade riders, in addition to the ones intended to keep them dry.

An alternate though more expensive and long-term solution could include building a full canopy over the bus bays, like at Pentagon station.

Whatever the solution, an escape from the heat is necessary for bus riders at Greenbelt station.

Diverging diamond: Faster traffic, worse for pedestrians

Diverging diamond interchanges (DDIs) are designed to move cars more efficiently by reducing the number of signal phases at interchanges and allowing cars on freeway on- and off-ramps to move freely without waiting for signals.

To accomplish this, the surface street lanes (not the freeway) cross to the opposite (left) side of the center line as they to pass through the interchange.

Pedestrians have to cross to the median and walk between concrete walls, forcing them to cross half of the through lanes at each side of the bridge. In the case of the Greenbelt Road/Kenilworth Avenue interchange, that would mean crossing 3 or 4 lanes (depending on the final configuration of the design) at each side of the bridge.

Alternatively, the design could accommodate pedestrians the outside of the roadway, but then they must cross the free-flowing left turn on- and off-ramps where drivers will be focusing on making the turn fast rather than looking for people crossing.

Incompatible with walkable vision for the corridor

What's most troubling is that the planning department is actually trying to create an urban, pedestrian environment immediately west of the interchange, yet they still proposed this design which does the opposite.

Early on in the presentation, planners showed before and after renderings of their visions for a walkable urban node where Beltway Plaza is today. They showed a suburban arterial transformed into a narrowed street with wide sidewalks, street trees, pedestrian lighting, and bike lanes. At previous meetings, they talked of building a street grid, of filling in parking lots with development, and making it easier and safer to walk in these new urban nodes.

They also talked of finding ways to link the different neighborhoods of Greenbelt that have been separated from each other by the various freeways in the area. They specifically mentioned finding better ways of linking the Golden Triangle office park with the Beltway Plaza area—two neighborhoods that are currently separated from each other by Kenilworth Avenue and its interchange with Greenbelt Road.

But planners are approaching rebuilding the Kenilworth/Greenbelt with the objective of moving more cars, faster. They are not thinking about creating a pedestrian-friendly environment in that space. They are not thinking about making cyclists feel welcome on the road.

And encouraging drivers to speed up as they approach what planners hope to be a walkable node is asking for trouble.

The cure is far worse than the disease

Today, Greenbelt Road crosses above Kenilworth Avenue at an interchange built in the 1980s. Most would agree that the intersection has its problems, mostly from the way the northbound ramps are offset and the close spacing of the north- and southbound off-ramps.

But the solution the county planners propose would be far worse than the current setup, especially for pedestrians and cyclists.

It is questionable why the county wants to focus on this intersection to begin with. It's not "failing" by traffic engineer standards, and in terms of driver delay, it's not even the worst intersection in the corridor, according to a study conducted in conjunction with the Sector Plan. But of course, highway engineers like to "fix" things whether or not they're broken.

Strong Towns executive director Chuck Marohn narrated a video about a DDI in Springfield, Missouri. A traffic engineer involved in the design created the video, touting how a pedestrian can walk through the interchange, but Marohn points out how absurd it is to say that this is actually pedestrian-friendly.

Marohn notes that while a DDI provides a path for pedestrians and cyclists, it's nothing like the kind of interchange one would design if the goal from the start were to make a space friendly to people walking and biking.

Building walkable communities and complete streets has to be more than an engineer running down an accommodation checklist. If we're trying to create a neighborhood where walkability is a primary goal, then pedestrians, cyclists, and transit users have to be a top priority, not just get the leftover road space and the bare minimum listed in the design guide.

The nascent urban districts at White Flint and Tysons Corner are transforming from suburbs to more walkable spaces. And like the Beltway Plaza area, pedestrians in those areas face barriers in the form of interchanges. Prince George's can't simply get rid of their interchanges, but they don't need to make the pedestrian condition worse by recommending converting an interchange to one that's sole purpose is to move cars more quickly.

Partially inspired by England's garden city movement, the planners intended for Greenbelt to be a self-contained community surrounded by a green belt of parks, forests, and farms. Today, Greenbelt is not as isolated, but the historic center maintains its park-like setting. The federal government sold off most of the original green belt in the 1950s and it was developed in typical suburban fashion.

The planners who designed Greenbelt had big ideas about creating a new type of community. One of the most revolutionary decisions was how to deal with cars.

Greenbelt was designed with the automobile in mind, but it was not designed for the automobile. This is the largest and most crucial difference between Greenbelt and the prototypical post-war suburb. The community is walkable, traffic is calm, and despite being surrounded by sprawl, cars do not dominate the landscape.

The planners created two independent circulation systems in the town: one for pedestrians and one for automobiles. As a result, the community has been described as "inside out." Pedestrian pathways wind through the community, providing access to the interior of residential superblocks and connecting residents to commercial and civic spaces. Five underpasses were built under the major streets to allow pedestrians to move through the city without encountering cars.

One effect of this design is homes with two fronts. On the "garden side," the homes front on the pedestrian pathways, and often on playgrounds and other green spaces. On the "service side," the homes open to the street (or in some cases, the parking court).

At the heart of the city is the Roosevelt Center, the town's retail hub. This area includes a grocery store, a cinema, and several shops and restaurants. The businesses are oriented onto a plaza, with the parking in the rear.

The city is oriented on a crescent-shaped ridge, with a lake and woodlands in the center of the crescent. The city was originally surrounded by a large greenbelt, though most of this has been developed. A good deal of greenspace remains within the community, however.

And while Greenbelt did not become the prototype for the American suburb, it did inspire other communities, including Columbia, Maryland and Reston, Virginia.

The real legacy of Greenbelt, though is in its residents. The history of activism and social engagement that was brought by the pioneer residents during the Depression has continued to be a part of life in the community.

If you're interested in celebrating 75 years of Greenbelt, the symposium is on Friday, April 27 and Saturday, April 28 in the historic community center. I'll be speaking on a panel about transportation on Friday afternoon. The deadline to register for the event is tomorrow.

Additionally, for more information and a tour of one of the original homes, you can visit the Greenbelt Museum at 10B Crescent Road every Sunday from 1-5 pm.