Sharrows & Safety & Shank Painter Road
There’s a blog post at Streetsblog that's making the rounds that says sharrows don’t do anything for safety: "Study: Sharrows don't make streets safer for cycling.”
I've been working with Provincetown 365 to advocate for bike pavement markings on a couple of streets in town where we have a lot of bicycles and no sidewalks or bike lanes, so I dug a bit deeper to see if the study was applicable to our streets here.
What this study says
The study's title is "The Relative (In)effectiveness of Bicycle Sharrows on Ridership and Safety Outcomes." I was curious about the conditions that the study's authors looked at and wanted to find out the road configurations (lane widths, number of lanes) and the speed limits on those streets. The blog post didn't mention those details and didn’t link to the actual study, so I reached out to Nick Ferenchak — one of the study authors — to find out more about the study’s details.
I asked specifically about his perspective on putting sharrows on low-speed (25 MPH) two-lane roads with narrow travel lanes (11 ft), which are the conditions on Shank Painter Road, and he said:
"If shared lane markings are used on bicyclist-friendly roads (it sounds like your narrow and slow roads may be bike-friendly) or as way-finding, they may very well be beneficial."
In looking at the Chicago data used in the study, it was interesting to see that the rate of bike commuting here in Provincetown is 4x that of Chicago (we are at 8% and Chicago is at 1.6%).
I tracked down the study online for more details. In short, the study looked at wide, multi-lane urban roads with 35 MPH speed limits. And it compared sharrows to on-street bike lanes. Their analysis was based on census commuter data, not actual observed trip counts, and didn't account for destinations or bicycle-friendly locations with bike parking.
The authors recognized the limits of their work and gave a caution about misinterpreting its conclusions. Here’s the section on page 15:
"While the conclusions of this work may be misconstrued by some as primarily a call to reduce the number of sharrows, the true goal of this research is to instead ensure that resources are focused on providing more bike infrastructure that has been proven to be effective at meeting its goals. This will most likely translate into more bike lanes in many scenarios."
The study didn't say sharrows were unsafe. It said that they weren't safer than bike lanes. That's like saying walking in the street isn't safer than walking on a sidewalk. Seems like common sense.
The sharrows and bike lanes proposed by Provincetown 365 are a tactical, interim solution until the road can be reconstructed with sidewalks and permanent separated bike lanes. (The town’s FY2017 Capital Improvement Plan has funds earmarked for this in 2021.) The Cape Cod Commission's 2012 Shank Painter Road Corridor Study and the 2015 DART Report both recommend adding bike lanes and sidewalks, but those improvements are years – and millions of dollars – away.
It's important to note that the current proposal isn’t just sharrows. It’s a combination of marked bike lanes, sharrows, and “bikes may use full lane” signs. It’s a baby step toward a goal of making town more bicycle-friendly through simple, inexpensive improvements that take our local context and experience into consideration.
Adding sharrows makes no change to the road's current layout. All that sharrows do is help educate everyone to expect bicycles. The proposed bike lanes fit in the existing layout where the road's fog lines were repainted a number of years ago. So adding bike lane markings helps reinforces the existing use.
I’ve discussed the idea of sharrows on our local roads with Lou Rabito (MassDOT’s Complete Streets Engineer), Glenn Cannon (Technical Services Director at the Cape Cod Commission), Barbara Jacobsen (Program Manager at MassBike), and Josh Zisson (a lawyer who specializes in bicycle law).
These experts all concur that sharrows are appropriate on our local roads where posted speed limits are 25 MPH or less. And from a technical standpoint, all current guidance from AASHTO, NACTO, and MassDOT indicates that sharrows should be placed in the center of the lane where lane widths are 12 ft or narrower.
Demand overrides conditions
I've been surprised at how people characterize some of our roads as "fast" or "highways" or "unsafe". Shank Painter Road, where we proposed this combination of bike lanes, sharrows, and "bikes may use full lane" signs, is used by lots of people on bikes and on foot despite its current configuration. It's not a comfortable street if you're not in a car, but people use it anyway.
There are numerous destinations here with lots of bike parking -- Stop & Shop alone has six bike racks for customers. The dog park has bike parking, as does the bank, church, the two housing developments, the gym, and most of the restaurants. (Oddly, the police station, fire station, and municipal pay parking lots are devoid of any public bike parking.) According to the property manager at Province Landing, the largest housing development on the street, residents own many more bikes than cars.
The speed limit here is 25 MPH and that's the fastest speed limit on any town road (with the exception of the state-controlled four-lane highway and the short segments of roadway the state controls and posts at 30 MPH). And in terms of safety, since 2012 there has only been one reported crash involving a bicycle and one involving a pedestrian on Shank Painter Road. The large majority of bike crashes in town take place on the bike paths in the Seashore, not on our local roads.
Sharrows are a good start
It seems that sharrows are an effective tool when used to remind everyone to expect bicycles on our streets. Most of our year-round residents took their drivers license exam decades ago before these treatments became common, so they seem foreign (they're in the current Massachusetts Driver's Manual). But to our hundreds of thousands of visitors from out of town, sharrows and bike lanes are part of the streetscapes they experience every day.
If town wants to increase biking and walking (which the Local Comprehensive Plan and town-wide policy goals do indicate) and educate everyone that biking is welcome here (which is an objective of the town's Bicycle Committee), pavement markings are a cheap and easy way to get started while continuing to plan for more substantial and permanent road improvements.
Study: Sharrows don't make streets safer for cycling, Streetsblog, January 2016
The Relative (In)effectiveness of Bicycle Sharrows on Ridership and Safety Outcomes, (paywall, $20 to purchase the study)
Provincetown 365 Shank Painter Road Bike Markings Proposal Slides, Facebook photos
Provincetown 365 Shank Painter Road Bike Markings Proposal Video, Facebook video
2012 Shank Painter Road Corridor Study, Cape Cod Commission
2015 DART Report, Town of Provincetown
Bike Safe Boston, blog of attorney Josh Zisson
Provincetown crash reports, getcrashreports.com
Province Lands Bicycle Accidents, page 24 of Outer Cape Bicycle & Pedestrian Master Plan's Phase One: Data Collection Transportation Data, Cape Cod Commission
Massachusetts Driver's Manual, Chapter 4: Rules of the Road, page 11
Provincetown 2000 Local Comprehensive Plan, Town of Provincetown
Town of Provincetown Provincetown Bicycle Committee, Town of Provincetown