Greater Greater Washington

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If car commercials were honest, this is what they'd look like

A sporty coupe glides joyfully along a seaside highway, all by itself. It's heaven for the anonymous driver. That's the standard, ridiculous car commercial.

This video shows what car commercials would look like if they were actually honest.

Cross-posted at BeyondDC.

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New road designs make Tysons more inviting for people on bike and foot

A street in Tysons just underwent some big changes, swapping driving lanes for bike lanes. The new design will make it easier to get around the area by bike and on foot.


Greensboro Drive's lane designs, before and after. Image from Fairfax County.

The stretch of Greensboro Drive from Spring Hill Road to Pinnacle Drive went on a road diet that cut its four lanes down to two. A center turn lane also went in, along with bike lanes in both directions.

The changes are the first of Fairfax's Proposed Street Design Update, which VDOT rolled out last March. Similar changes are coming to Tyco Road and Westbranch Drive.


The new Greensboro Drive. Photo by the author.

Greensboro road feeds an employment hub that's home to companies such as Booz Allen Hamilton, Cvent, and SAIC.

The new turn lane should lessen traffic backups since cars used to get stuck behind people waiting to turn left off of Greensboro. And the bike lanes should also make it easier to reach the new Silver Line Metro stations. Already, I've seen an increase of people walking to and from both the Greensboro and Spring Hill stations.


Greensboro Drive prior to the changes. Base image from Google Maps.

For the time being, Greensboro Drive between Pinnacle and International Drive, closer to the Tysons Galleria mall, is still four lanes wide. But it's good to see the beginnings of a thoughtful, pedestrian- and bicycle-friendly design emerging in Fairfax County's redevelopment of Tysons.


One of Greensboro Drive's new bike lanes. Photo by the author.

The Metropolitan Branch Trail could learn a thing or two from Chicago's new bike trail

Chicago's new 606 trail is already very popular for biking, running, and walking, in large part because it's full of attractive landscaping and user-friendly amenities. DC would be smart to take some ideas from the 606 for upcoming changes to the Metropolitan Branch Trail.


All photos by the author.

Chicago opened the 606 in June. Also known as the Bloomingdale Trail, it stretches 2.7 miles, behind homes and under the 'L' — Chicago's Metro — through four of the city's neighborhoods.


Sapling trees and shrubs line the 606, with benches and water fountains available at major street crossings. That might explain why, even in near 90-degree heat on a recent Sunday, there was a steady stream of cyclists, runners and pedestrians using it.


Among the trail's eye-catching features are arches over one bridge and a fake railroad truss over another.


The fake railroad truss that runs over 606.


Benches on a bridge along the 606.

One thing people who I talked to complained about is the 606's lack of shade. However, they all acknowledged that it will correct itself as the saplings grow up.


The future 606 in 2011. What a difference a few years make!

Like the MBT did for near northeast Washington, the 606 has created a new off-street transportation corridor in Chicago's cycling and trail network where none existed before. But the 606 is also much more: it's a public space with grassy knolls where residents can put down a towel and relax and shaded glades with benches to sit on.

The MBT could steal an idea or two

The NoMa Business Improvement District has some plans to improve the MBT. These include a small park just south of where it passes under New York Avenue, new gardens and neighborhood connection and safety improvements.

Using the 606 gave me a few ideas on how to make the MBT both more pleasant and inviting.

Benches on the bridge where the MBT crosses Florida Avenue NE could create a new vista of the never-ending traffic drama around the so-called Dave Thomas Circle.

Water fountains could go in at key intersections, like at R Street and the entrance to the bridge to the Rhode Island Avenue Metro station that opened in December.

Landscaping on MBT could also get better. While young trees line part of the route, there's room for more, especially to the stretch between R Street and Rhode Island Avenue.

In addition, regular maintenance of the existing landscaping—like cutting the grass—would do a lot to improve the aesthetics. And a better-looking trail would likely invite more users, which is important since one of the preliminary findings that the BID shared with the public was that people would feel safer on the MBT if more people used it overall.


The uncut grass along stretches of the MBT create a wild prairie aesthetic.

The MBT is set to get longer in the next few years, with the addition of a section that connects Brookland to Silver Spring. Taking a few cues from Chicago's 606 might make both the addition and the existing trail an even better public space for the District.

To bike across the Potomac, most use the 14th Street Bridge or Key Bridge

Most cyclists cross the Potomac River on either the 14th Street Bridge or Key Bridge. Even more people might use these bridges if there were more ways to get to them by bike.


Graph by the author.

On the average July weekday this year, each carried around 2,000 riders: it was 2,028 for the 14th Street Bridge, and 1,950 for the Key Bridge. The Roosevelt Bridge saw an average of 474 cyclists per July weekday.

An average of 3,013 cyclists used all three bridges on weekdays during the first seven months of 2015. This equals an average of 1,352 cyclists on the 14th Street Bridge, 1,338 on the Key Bridge and 324 on the Roosevelt Bridge.

This data comes from Arlington County.

Cyclists can also cross the Potomac River on the Chain Bridge, Memorial Bridge and Woodrow Wilson Bridge, but there is little data available on exact use.

Cycling peaks during the summer

Bike commuting across the Potomac is most common during the relatively pleasant late spring and summer months. An average of 4,453 cyclists crossed the river on the three bridges during weekdays in July.

People used the Potomac crossings least during the winter. An average of 973 cyclists used the bridges on weekdays in January—about a fifth of the number that used them in July.

Cyclists face treacherous conditions during the winter months when the 14th Street Bridge path and the Mount Vernon Trail, which connect to all three Potomac crossings, are not plowed.

Interestingly, the annual Cherry Blossom Festival in March and April does not result in a spike in weekday cycling traffic across any the Potomac. This could be because bike commuters prefer to avoid the crowds around the Tidal Basin where they access the 14th Street Bridge in DC. It could also be that many have yet to resume cycling after a winter hiatus.

Better connections to the 14th Street and Key Bridges would serve a lot of cyclists

The 14th Street Bridge connects to the Mount Vernon Trail in Virginia, where cyclists can easily continue on to Crystal City, Ronald Reagan Washington National airport and Old Town Alexandria. Ideas for better connections include ones to the Pentagon and Long Bridge Park, potentially as part of the Long Bridge replacement.

In the District, the bridge drops cyclists just south of the Jefferson Memorial. From there, they have to ride on the sidewalk or with traffic across the Mall to reach the city's protected bikeway network. Ideas to improve the connection include extending the protected bikeway on 15th Street NW to Constitution Avenue, adding signage to the route and widening the off-street path.

The Key Bridge is well connected to the Custis Trail, Mount Vernon Trail and Rosslyn in Virginia. But on the District side cyclists either have to ride with traffic on congested M Street or descend two sets of stairs to reach the Capital Crescent Trail and K Street. The Georgetown Business Improvement District's Georgetown 2028 includes some improvements to the District side, as well as a new crossing to Roosevelt Island.

Complex traffic signals make streets less safe

Streets across the United States are often difficult and dangerous to walk on because wide lanes invite drivers to speed. That isn't all that makes them dangerous, though: many also have signals that distract drivers and draw their eyes away from the road.


Arlington's Intersection of Doom. Drivers who want to turn right in order to travel north from the eastern side of the intersection have to account for oncoming north-bound cars, people crossing from all directions, and confusing signs. Photo by the author.

A case in point is the "intersection of doom" where the Mount Vernon Trail turns into the Custis Trail at the foot of the Key Bridge in Arlington.

Drivers exiting I-66 are allowed to make right turns on red, except during a brief "leading pedestrian interval" when a walk signal gives pedestrians and cyclists a head start across North Lynn Street before the traffic light turns green. But it's hard to see how drivers can make this turn safely without extra eyes on both sides of their head.


Base image from Google Earth.

Drivers must simultaneously watch for cars coming from the left, cyclists and pedestrians entering the crosswalk from the right, and an overhead signal that went in in January that flashes a no-right-turn graphic for a few seconds during the leading pedestrian interval.

To make things worse, the no-right-turn graphic is hard to see in bright light, and it is flanked by highly visible signs that seem to say turns are allowed.

Diligently watching the short-lived no-turn signal while looking for a gap in oncoming traffic from the left would make it nearly impossible to look to the right. A driver trying to legally turn right on red has no time to look toward the sidewalk on their right and can't see whether someone is about to enter the crosswalk and pass in front of their car.


Overhead signs at intersection of doom, with the no-right-turn sign illuminated.
Photo by the author.

Dangers like these are widespread on American streets. What makes this intersection stand out is the heavy bike and pedestrian traffic, not the arrangement of the signals.

Tell drivers what they need to know, and repeat it

From an engineering point of view, the information traffic signals send to drivers is part of a control system that must operate reliably to keep roadways safe. So is the drivers' reaction to that information.

The traffic engineering establishment certainly recognizes that human behavior affects road safety. But two concepts are conspicuously missing from its guidelines on human factors in signal design: redundancy and parsimony.

Redundancy means backups for missed signals and improper actions. Parsimony means signals aren't excessively complex.

It's easy to see redundancy's value. Intersections with simple red-yellow-green traffic signals are full of redundant information: The movement of vehicles and pedestrians is a cue to when the light changes, so drivers don't need to stare at the signal and can keep watch on the street.

More complexity—turn arrows, walk signs, rules that allow right turns on red—means less redundancy. Demands on the driver's eye and brain increase, and the inevitable moments of inattention do more harm.

Parsimony is a less intuitive idea, but an equally important one. This principle, which originated from the statistical analysis of time series, warns against using too many input variables to control decisions. Adding complexity, when there aren't enough data to do it right, makes outcomes worse.

Consider the countdown clocks attached to walk signals. The Federal Highway Administration mandated them when research indicated that when pedestrians know how much time is left before cars start to move, they get hit by drivers less often. But this information changes the behavior of drivers too. Whether the drivers speed up to beat the light or simply get distracted is not clear, but the effect is real. A recent study in Toronto found that countdown timers cause more collisions than they prevent.

Complex signals have other costs. Turn arrows make signal cycles longer. This gets more cars through the intersection, but everyone waits longer for a green light and the street becomes a barrier to walking. The delays to pedestrians and non-rush-hour drivers may exceed the time saved from reduced congestion—but the traffic engineers won't know without data on off-peak travel, something they rarely measure.

And slow lights create safety hazards of their own. The longer pedestrians are asked to stand and watch a don't walk signal, the more likely they are to ignore it.

It will never be possible to govern traffic with the mathematical precision of electric circuits. But they are both control systems afflicted with random noise, and similar principles apply.

Solving problems by adding more gadgets to an already complex system can do more harm than good. Traffic control operates most reliably when everyone on the road knows that green means go and red means stop.

Turn arrows and separate walk signals should be used sparingly. They squeeze more cars through an intersection in rush hour, but they exact a price in safety, dollars, and travel delay.

Traffic engineers need to balance vehicle throughput against the benefits of redundancy and parsimony. In any control system, and especially in one that relies on the actions of human beings, simplicity has to be a priority.

Check out Dublin's bikeshare system, and compare it to ours

dublinbike, the biggest bikesharing system in Dublin, Ireland, opened in 2009, a year before Capital Bikeshare. Put side by side, the two make it easy to see how one transit system can learn from another.


Photo by William Murphy on Flickr.

dublinbike had 450 bikes and 40 stations when it started, and it added 100 bikes and four more stations in 2011. By contrast, CaBi started with 400 bikes and 49 stations and has since grown to have over 3000 bikes and 300 stations.


dublinbike dock. Photo by author.

CaBi's much faster expansion might be because stations are cheaper to install. While CaBi's stations are all above ground, the wiring at dublinbike docks is all embedded underneath the asphalt. Having to dig up pavement to install a station costs a lot more money than simply setting one down, and it's possible that its installation costs will slow dublinbike's plans to expand.

The two systems' designs encourage different kinds of use

The dublinbike bikes themselves come with a little lock in their baskets in case you want to hold on to your bike without docking it. It's quite handy if you want to venture away from a bike for just a brief moment, like to run into a shop or walk through a park.

CaBi bikes don't come with locks, which means you almost always have to dock a bike if you're not using it. This helps ensure bikes for people who want them just for short trips.


Dublinbike basket with mechanism. Photo by author.

Dublin also doesn't have any 24 hour memberships (which cost $8 in DC), only offering a three-day membership instead for 5 Euros (about $5.50). Combined with the option to lock bikes up wherever, this makes me think dublinbike made a conscious decision to cater more to tourists than CaBi.

Dublin is a pretty bike-friendly place. People there ride all sorts of bikes, and the network of bike lanes is about as big as DC's. There's a network of two-way protected bike lanes all around the airport, as well as a wide network of bus lanes that people can ride in, which amounts to an additional lot of super-wide bike lanes.

dublinbike is quite popular, and it's one of the world's great bikeshare systems. While DDOT drew most heavily on Copenhagen's system when planning CaBi, it makes sense to think Dublin's played at least a small part in helping shape CaBi into the success that it is.

Petworth residents say changes to a dangerous traffic circle should go further

Many people in Petworth lament how dangerous it is to cross the street and get to Grant Circle, one of their neighborhood parks. DDOT has an initial plan for addressing the problem, but pedestrian advocates say the real way to make the circle safer is to make the streets narrower and add more crosswalks.


Photo of Grant Circle by Eric Fidler on Flickr.

Like a lot of circles in DC, Grant Circle has a design that's invites people to use the interior space as a park but, more recently, has made moving traffic between its several intersections a major priority.

Drivers tend to speed through Grant Circle, partly because it has two wide lanes surrounding it that encourage passing. With drivers entering from the eight different intersections around the circle, and sometimes speeding to pass each other, it can be a harrowing place for people on foot or riding bikes.


Streetview of Grant Circle today. Image from Google Maps

Every few months, a new thread starts up on the Petworth neighborhood listservs about near misses or actual crashes around Grant Circle like one last week, when someone drove their car into the circle.

"Grant Circle is an absolute mess for pedestrians," wrote one resident recently. "When I drive, I often hesitate to stop for pedestrians because I know cars will zoom around me and make it much more dangerous for the people that are crossing. When I do stop I often go between both lanes to try to ensure the pedestrian safety which is obviously not the best thing to do."

While well-intentioned, that second solution obviously isn't a safe alternative to Grant Circle's hazards.

"The design of the circle is so wide and big that instead of helping to slow down cars, it makes them to speed up," added another. "If so many of us have already had nearly misses, some tragedy will end up happening."

Plans to calm Grant Circle's traffic have fallen short of a bigger vision

After hearing from community members and ANC commissioners, DDOT released initial plans to both add new striping to the streets around Grant Circle and to narrow their lanes. Both should calm traffic as it enters the circle.


DDOT's immediate plans to add striping to Grant Circle to narrow lanes and calm traffic as it enters the circle. Image courtesy of DDOT.

This is a step in a process that started in 2009, when DDOT completed its Pedestrian Master Plan. The plan's goals were to make it safe and comfortable to walk anywhere in the city, both through city-wide policy solutions and targeted changes to certain streets' designs.

The Master Plan placed a heavy focus on L'Enfant's radial avenues, which is where the majority of today's crashes involving pedestrians happen. It plan designated "priority corridors" in each ward, which were places that saw a lot of pedestrians, had a dangerous design, and had a lot of crashes involving pedestrians as a "priority corridor."

New Hampshire Avenue, including Grant Circle, is Ward 4's priority corridor, and it was slated to get bumpouts along New Hampshire and a new design to calm traffic around the circle. These plans represent a more complete vision to calm traffic than the initial striping DDOT is proposing, though new ideas in traffic engineering could help even more.

Grant Circle's two-lane design is needlessly dangerous

Every street intersecting Grant Circle is one lane in each direction, except for New Hampshire Avenue south of Grant Circle. There, New Hampshire has two lanes in each direction until it turns into Sherman Avenue, which has one lane in each direction.

If New Hampshire has one lane in each direction north of the circle and again a few blocks south, does it really need two lanes in the first place?

The two lane design means that parents with kids, dog owners with dogs, elderly people and those with disabilities, and anyone else trying to get to the park have to contend with serious traffic, which enters the circle from eight different points, to do so. And while relatively few cars use the passing lane, those that do tend to speed and pose an extra risk to people walking.


Grant Circle today. Image from Google Maps

Let's consider some possibiltiies

All Walks DC, an organization I'm a part of, has a few thoughts for how Grant Circle could be made safer to walk and bike to and through.

When you look at Grant Circle's interior paths, you can see where the original designer intended for people to be able to cross into and through the circle (though for some reason it leaves out paths to 5th Street NW). But out of the 12 places that those interior paths intersect Grant Circle, only 5 have crosswalks today. Some streets, such as Varnum on the East, don't have any crosswalks at all, meaning that all the neighbors on that street have to walk a block south to use a marked crosswalk.

One simple fix would be to to add the crosswalks that are obviously missing.


DDOT's 2009 plans for Grant Circle include a raised brick inner lane to calm traffic. Image from DDOT.

Narrowing Grant Circle to one lane would make crossing on foot much safer. DDOT's 2009 plan includes a proposal to make the inner lane raised brick, which is a half step in this direction. But while this would discourage speeding and passing, it would likely be expensive, and there are probably better uses for that space.

For a lot less money, DDOT could bring down speeds and make Grant Circle more pedestrian and bike-friendly by allowing parking in the inner lane and building bumpouts at all the crosswalks.


Bumpout on 18th Street in Adams Morgan. Image from Google Maps.

DDOT could also car lanes by creating a protected bikeway, which the Move DC plan calls for, along the outside of the circle.

Finally, it's worth considering using lanes to increase park space, which has happened in New York City. Extending Grant Circle outwards would be more complicated due to coordination with the National Park Service, but would add about a half acre to the area of the park.

Calming traffic around Grant Circle is an important part of kicking off DC's Vision Zero efforts, as it would be an example of a community-supported project to make a street with known dangers safer for people walking. Several residents have already noted dangers around Grant Circle on DDOT's Vision Zero map, which you can view and add to here.

If you live nearby and would like to sign a petition for a safer Grant Circle, click here.

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