Protected bike lanes on Quincy St are taking small steps forward, but it’s complicated, says Arlington’s transportation department.
On Monday, September 19, WABA’s Arlington Action Committee hosted an update from Arlington County staff on their progress designing a protected bike lane on N. Quincy St. in Ballston. Staff presented work done so far, a summary of the constraints and trade-offs for upgrading Quincy’s existing bike lanes, and a preliminary design concept for a few key blocks.
Since November 2015, the Action Committee has worked with local residents, business owners, and civic associations to build support for a north-south, protected bike lane to link the Custis Trail to points into Ballston. Six months ago, after an outpouring of support, the County Board directed Arlington’s County Manager to develop concepts for protected bike lanes on Quincy St. Now, Department of Transportation staff have taken a close look at the corridor and identified an important opportunity and key challenges to weigh as the design moves forward. We were delighted to spend the evening discussing the study with Arlington Director of Transportation Dennis Leach, Design Engineer Team Supervisor Dan Nabors and other staff. Here is what we learned on Monday:
A Repaving Opportunity
A large section of Quincy Street, from Glebe Road to Fairfax Drive, is in rough shape and is already slated for repaving next year. Since repaving is often the largest cost for a bike lane project, this is an ideal time to consider how the road can be restriped once new pavement is installed.
To take advantage of this cost-saving opportunity, staff have focussed on designing this 0.4 mile section through Ballston’s densest blocks. Beginning with a survey of existing conditions, striping configurations, curb to curb distances, and road geometry, they identified some constraints that require careful design moving forward.
Space Constraints and Other Challenges
In a dense urban area like Ballston, space for moving people around is limited. Roads and sidewalks are flanked by rows of buildings atop a tangle of public and private land. Upgrading bike lanes requires additional space on the road to safely separate bicyclists from car traffic. And while it may seem simple to upgrade a lane on one block, the same amount of road space is needed on every block.
Dimensions for on block of Quincy St. from Wilson to 9th N. Click to download full doc
Quincy St. is not a uniform width from one block to the next. The distance between curbs ranges from 41 feet to over 70 feet at some intersections, allowing for traffic lanes, turn lanes, curbside parking, the existing unprotected bike lanes, and sidewalk extensions. This variability makes it difficult to create a single street design that fits on every block. And where the street narrows, an engineer can only squeeze bike, traffic, and parking lanes so much.
In narrow blocks, we face a question of priorities. Should the County use limited public space to encourage more people to travel by bike or should it dedicate public space to car parking? To create a fully protected bike lane, some parking must be removed. Yet to retain every parking space, only minor bike lane improvements are possible on most blocks.
Another complication that limits available road space are the frequent curb extensions or “nubs” along Quincy St. This common traffic calming treatment extends a sidewalk into the road at mid-block crossings and intersections to improve pedestrian visibility and shorten crossing distances. Despite their benefits, curb extensions create more fluctuations in road width and complicate bike lane design on narrow roads. Fortunately, protected bike lanes can offer similar benefits to pedestrians, but installing them may require tearing up concrete, which increases construction costs.
Preliminary Design Concept
To illustrate some of the trade-offs, County staff presented one of many possible concepts for protected bike lanes on Quincy St. from Glebe Road to Fairfax Drive. The image below shows a protected bike lane running against each curb and separated from moving traffic by flex posts, parked cars, and a painted buffer area. This design offers a low-stress, separated place to ride that can reduce speeding, reduce bicyclists riding on sidewalks, discourage parking in bike lanes, and attract more tentative riders with a low-stress, trail-like experience. Click here to download the full design (pdf).
Potential protected bike lane concept and parking impacts. Click to download full document pdf
On some blocks, these upgrades would require changes to on-street parking. Orange areas indicate existing parking that would remain. Green shows additional space for parking. Red shows areas where existing parking would need to be removed. Under this draft concept, some blocks would retain all current street parking, while others might see reductions in street parking. It is worth noting that parking studies of each block show relatively low parking utilization and that a surplus would still remain if some spaces were eliminated. Furthermore, Quincy St. boasts numerous off-street garages and parking lots along the corridor.
Potential parking impacts for a block on the corridor
Experience a Quincy Street Protected Bike Lane at Saturday’s Arlington Fun Ride
On October 1st, we are teaming up with Phoenix Bikes to create a pop up protected bike lane on Quincy Street to show what a low-stress bike lane could do for Ballston. Last year’s ride was a huge success, and this year participants of all ages can feel the joy of a protected lane on their way from the Custis Trail to the Ballston pit stop at the Central Library. The ride is fun for the whole family, offers a distance for every rider, and supports a great cause! Learn more and Register Here!
Photo from last year’s Arlington Fun Ride (Photo by JSanchez)
While these drawings may look polished, they represent only one of many possible configurations for a Quincy St. protected bike lane. Lanes with different geometry and dimensions, or even a two-way protected bike lane, could suit the space better, and more design work needs to be done to explore those possibilities. As spring, and the start of next year’s repaving season approaches, we hope to see more solidified options and a clearer understanding of the trade-offs and benefits. We are confident that with an open dialog and opportunities for input that we can find a solution that works for Quincy St. residents, visitors, commuters, and businesses.
For more on the Bike Friendly Ballston campaign, click here.