The recent design charrette has provided a little controversy for our city and for engaged bloggers. Should downtown convert its street grid from one-way to two-way streets? Divergent views are already emerging.
Explaining and defending the charrette’s recommendation of a two-way street conversion downtown is Buttermilk & Molasses. John’s post “THE DOWNTOWN PLAN: ONE-WAY OR ANOTHER” ably presents the controversy and advocates for the conversion.
Representing concern over this proposed change is the Richmond Business & Commercial News blog in the post “Ending One-Way Streets in Richmond?” A local traffic engineer, Bear, joins the debate in the comments section with data and sound logic advocating for the status-quo.
The controversy has also made its way to Richmond City Watch’s forum, an on-line forum for all things Richmond, with a focus on architecture & urban planning.
Check out Bear’s posts here (covering similar ground) and the many responses in the forum’s Downtown Charrette discussion.
I’ve spent the afternoon researching the claims each side is making and trying to determine if there is a clear case to be made for either side. Most arguments on both sides of the local debate center on making downtown a safer and more inviting environment for non-motorists, a goal almost universally shared.
My view: there is no obvious choice here.
The smoking gun for my ambivalence is the Federal Highway Administration’s Pedestrian Safety Report on “One-Way/Two-Way Street Conversions,” which concludes that compelling reasons exist for both types of streets from a pedestrian safety perspective.
Reasons for converting to 2-way streets:
- Slower traffic speeds.
- Decrease “Vehicle Miles Traveled” by eliminating indirect routes (driving around the block to get to your destination).
- Increased access to businesses.
- Possibly: safer for pedestrians.
Reasons for maintaining 1-way streets:
- Conversion is very costly.
- 1- way streets allow for more cars, thereby decreasing congestion.
- Easier than 2-way streets to time stoplights (timed lights improve traffic flow and decrease idling (& therefore pollution)).
- Fewer turn prohibitions.
- More on-street parking.
- Possibly: safer for pedestrians.
A note of clarification: turns are often prohibited on heavily traveled 2-way streets to maintain traffic flow (think Hull St. in Manchester, or Boulevard during rush hour). On-street parking is sometimes lost as the extra lane used for parking is reclaimed for travel purposes. And both sides in this debate argue that their choice is the safest for pedestrians.
Unfortunately, most of the information I found about the pros and cons of converting streets was written by highly partisan organizations which were promoting ideological arguments for or against automobile-oriented development. These studies were less academic in nature and more akin to propaganda. I searched academic databases, government sites, and google. At any rate, here’s a rundown of studies I found helpful.
One of the better studies was published by the Transportation Research Board, “Downtown Streets: Are We Strangling Ourselves on One-Way Networks?” which advocates for 2-way streets. “This paper provides a comparison of one-way versus two-way street systems for downtowns and presents an evaluation methodology for considering two-way conversion.”
The study discusses Bear’s comment on the Business & Commercial News blog that “One-way streets eliminate conflict points” and argues the opposite. The heart of the issue is, in my own blunt rewording, from how many directions can pedestrians be hit? Bear and others argue that 1-way streets provide fewer “conflict points,” while the Transportation Research Board argues that 1-way street networks provide many more possible types of street intersections. Examples include a 1-way street intersecting with another 1-way street, a 1-way street intersecting with a 2-way street, and a 1-way street which becomes 2-way at an intersection (think Main & Cary sts. where they convert to 2-way). 1-way street networks increase the variety and kind of conflict points creating more confusion for pedestrians and motorists.
The highly technical article “A MICROSCOPIC SIMULATION STUDY OF TWO-WAY STREET NETWORK VERSUS ONE-WAY STREET NETWORK” argues that, “one of the inherent disadvantages with one-way street is that they force additional turning movements at the intersections caused by motorists who must travel “out-of-direction” to reach their destination. The additional turning movements for a one-way street network increase the occurrences of vehicular-pedestrian conflicts at any given intersection, and also result in a system-wide increase in vehicle mile of travel (VMT) as compared to a two-way street network.”
In other words, you have to turn more on a 1-way street network, and therefore have more chances of running over people.
I found both of these sources on Streetsblog.org, a NYC-focused blog with a helpful article arguing against converting streets to one-way in Brooklyn.
On the other side of the debate is the Center for the American Dream of Mobility and Homeownership’s paper “No Two Ways About It: One-Way Streets are better than Two-Way.” The most convincing evidence produced in this paper is that pedestrians were hit more frequently after streets were converted to 2-way in several downtowns in the US. I’d prefer to cite those studies directly rather than this obviously partisan article, but I could not track them down on-line. The references in this article contain a lot of garbage (highly ideological publications, newspapers, and studies more than 50 years old), but the empirical evidence cited about the number of accidents resulting from recent 2-way conversions is convincing.
I am personally biased towards 2-way streets. They put less emphasis on moving as many cars as possible, they slow traffic, and provide a more inviting atmosphere for pedestrians. However, I’m not sure that compelling enough evidence exists for their benefits in a downtown region to justify the expense required to do a full-scale conversion.
What I’d like to see is more empirical evidence for the claims of both sides, focusing on the many regions which have recently switched their downtown street networks. Denver, Raleigh, and Cambridge, MA, among many others, have recently done this. What’s their experience been? Has downtown experienced a resurgence? Have their been fewer or more pedestrian accidents?
The issue of pedestrian accidents is a salient one for Richmond. We have the dubious distinction of placing 2nd in large Metro areas with worsening pedestrian safety (Orlando’s number 1).
Richmond-Petersburg, VA MSA in 1994-95 scored a 41.4 on the “pedestrian danger index” and a 70.5 in 2002-03.
The danger index is a measure of the average yearly pedestrian fatalities per capita, adjusted for the number of walkers. In other words, a lot more people are getting run over by cars.
Of course, I doubt many of those accidents occurred downtown, likely they’re in Midlothian and Short Pump. But it seems like a discussion of improving pedestrian safety, downtown and around the rest of the metro area, is timely.
July 29, 2007 at 12:24 pm
Excellent summary with good examples. I’m also generally ambivalent about the issue, and tend to fall into the “convert some, not all” category. That said, as I mentioned in my post at Buttermilk & Molasses, I believe the starting point of the discussion has to be around what the desired outcomes of conversion are.
While Bear makes many sound arguments for maintaining one-way streets, his dismissal of planners as having any value to add to the debate is dubious. The bottom line is that planners, policymakers, traffic engineers are residents were involved in the Dover Kohl discussion on one-way vs. two-way, and there seemed to be general agreement about converting most one-way streets into two-way streets.
The ultimate outcome — as I understand it — is to move commuter traffic away from certain neighborhoods; increase the cohesion of some neighborhoods; and reduce confusion among tourists and some-time visitors. (Just yesterday, I watched a SUV from New York turn right from Franklin onto 9th Street (which is starts its one-way restriction at Bank Street) and come close to getting t-boned as he headed the wrong way across Main Street.)
I think converting to two-way just for the sake of change is stupid. Converting with an ultimate goal of adding more public transit, better bike access, smoother transitions into pedestrian spaces makes sense. As an urban planning neophyte, my views aren’t rooted in one school of thought versus another — just in seeing downtown Richmond become more vibrant and multi-purpose.
July 29, 2007 at 1:38 pm
Without backtracking… my beef is not with planners, although as a pedestrian safety expert and advocate I have some trouble with them not being held accountable for the end result of their recommendations. I apologize if that makes me dubious, I would call it frustrated after a week of participating and sharing in a charrette, I figured the ball would move and did move in private; however, not for the big show.
My beef is that this whole discussion takes us off focus from the true issues of pedestrian barriers (ie interstates, freeways) and takes us from the city center project concept found between Marshall and Grace 5th to 7th. Intersection curb extensions and narrower streets in a one way system creates a safer and more inviting pedestrian experience with the right urban form that was absolutely the forte of D&K.
It seems that most conversations here are centered on pedestrian safety. Over the time I was with the City, pedestrian crashes went from 150 crashes to about 90 per year. (Don’t confuse the MSA statistics with the City proper, the city is much more pedestrian friendly than the sub or exurbs) There is also a Richmond Regional Bike /Ped Plan at their website. One of the big reasons for this drop in ped crashes is a fundamental philosphical change in how we timed traffic signals to encourage pedestrian activity. Since 2000, the downtown has experienced tremendous growth. At the same time we adopted a policy at every downtown traffic signal, a pedestrian can get across the street usually in less than a minute wait. There is no need to push a button and their are no long waits.
It’s time to further this positive achievement to incorporate even slower progression speeds. The only mistake I made in 1999 was when I set the progression speed to 31MPH (figuring correctly that most vehicles travel 5-6 MPH faster than the posted speed limit; I did not know the now widely held fact about the biomechanics of the human and survivability of pedestrians at even 30MPH as they were not widely known. It is also widely now known that the more pedestrians or cyclists that are present, the safer that all non-motorized users are (see netherlands studies). Drivers expecting to see pedestrians modify their behavior appropriately. The worst areas in the downtown for pedestrian crashes are generally the wider streets of Belvidere and Broad Street. Curiously they are also high on Grace Street west of Belvidere and Main Street in Shockoe Bottom. Some are because of exposure (as in the wider streets). Some are alcohol related (see the Bottom). But the one that stands out, is Grace Street in the VCU section (not wide) Franklin Street does not have the pedestrian crashes that Grace Street has. Franklin is one-way. Grace is two-way.
What most folks don’t understand is that pretty much every time a motorist turns, they see a red light because of how the lights are timed. In addition, one way streets also allow for separation of decisions for the driver. Instead of 32 conflict points in one spot, the driver only has to deal with 8 and it is easier for the driver to focus on pedestrians and where they are instead of the oncoming vehicle and what they may do. There are also ways to control the speed at which turns can be made (see city center example). Most drivers yield at 15MPH. In addition, Richmond has very short, walkable blocks. Two way streets on our short blocks will not be able to support the current land use density.
Over time, most traffic engineers have come to see the error of their ways about the now defunct policy of seeing how many vehicles they can move through a certain point and have become more balanced from what is taught in most civil engineering curriculums. The really good ones can build a transportation system that is safe and effective in creating the perfect mixed used community. Let’s focus on making improvements that we know will work with real benefits instead of focusing on this red herring issue of one-way vs two-way.
July 30, 2007 at 9:03 am
In the city where I work, most of downtown is one-way streets. We have at least six cars each and every day going the wrong way on the street in front of our business. The traffic light at the corner has several near misses every day and an accident every couple of weeks. Besides the fact that the speed limit is 25mph and everyone does at least 40mph. These one-way streets and intersections are very dangerous.
July 30, 2007 at 10:39 pm
Bear, if you come back to this site…
At what website can I find the ped/bike plan you mention?
And another question: one of those articles I linked to suggests that a mixed 1-way 2-way street network is actually dangerous because every intesection has different conflict points. That might suggest why Grace west of Belivedere has accidents. Think about the rest of the fan, however, where every street is 2-way. There’s no confusion about where to look, you look both ways at all times. Could that be a possible explanation for the Grace St. anomaly?
That also makes me nervous about the half-way conversion of downtown- if we make our street network even more confusing than it is already, people will have NO idea where to look when turning or walking. Which streets are 2-way, which are 1? I think perhaps consistency is more important than anything else for the sake of motorists and pedestrians.
By the way, anyone see Sunday’s op-ed piece calling for bike lanes? And not just bike lanes, but phyiscally separated bike routes? Good stuff, though print only, as far as I can tell.
July 31, 2007 at 9:31 pm
AMBRICH: Be happy to… http://www.richmondregional.org/Publications/Reports%20and%20Documents/Richmond_Regional_Bicycle_%20Ped_Plan.pdf
I also agree that consistency is key. Any minor traffic change will cause a spike in crashes. Primarily, the mix of intersection types also cause the driver andpedestrian to be confused. The best scenario is all one way with the wider streets to continue to be two-way. The City will run out of money soon after it begins so like two streets might be converted. By the way if any federal money is spent they will have a tough time getting approval because they have to prove safety is not compromised and that no additional pollution is created. Very difficult. Also, they have to make sure that the pedestrian is not adversely affected… very difficult.
August 2, 2007 at 10:34 am
I don’t think I’m a fan of separated bike lanes actually. I think we just need more bikes on the roads and car drivers need to get a clue and realize that the roads are not just for cars. It has also been my experience from biking around the city that drivers are much more jerks when you bike on one-way or divided roads than when you bike on two-way roads. Go figure.
February 27, 2008 at 10:26 pm
[...] The Urban Richmond blog took some time to break down some of the arguments for and against such a conversion. The arguments are nowhere near cut-and-dried either way. [...]
March 4, 2008 at 4:28 pm
Benefits of One-Way Couplets
Studies were conducted from the 1930’s to the 1970’s of ‘before’ and ‘after’conditions as cities switched from two-way to one-way streets. Almost universally they found that one-way streets had 10-20% lower accident rates than when previously two-way. Most significantly, pedestrian accidents declined far more, by 30-60% (see pages A-126; A-162, ‘National Highway Safety Needs Study, Appendix A’, Research Triangle Institute, March 1976 (DOT-HS-5-01069); Pages 7-2 to 7-8, ‘One-Way Streets and Reversible Lanes’, Synthesis of Safety Research Related to Traffic Control and Roadway Elements, Volume I, Research Triangle Institute, March 1976 (FHWA-TS-82-232), December 1982; Page 28, Dr. Charles Zegeer, University of North Carolina, ‘Pedestrians and Traffic-Control Measures’, National Cooperative Highway Research Program, Synthesis of Practice, #139, November 1988; and Chapter 10, Peter A. Mayer, Chapter 10, ‘One-Way Streets’, Traffic Control and Roadway Elements, Their Relationship to Highway Safety, Highway Users Federation for Safety and Mobility, 1971).
Few cities that have made the mistake of converting one-way to two-way will release accident impact data on this change, Two that have, Denver and Lubbock, both show magor increases in accident rates as a result of reverting to more dangerous two-way trafffic. Typically, studies favoring two-way avoid any real before and after data on vehicle or pedestrian safety or avoid the safety issue altogether. My published writings, the only ones that show this type of data, were described as “ideological” by the UrbanRichmondBlog. I guess they feel people getting killed or injured is an “ideological” issue of little interest. Two-way streets typically have twice the pedestrian accident rate of one-way streets so they are definitely not “pedestrian-friendly”, as is widely being claimed now.
In 1959, the Oregon State Highway Department published a report which summarized the overall impact of converting two-way state highway sections through town and city centers to one-way couplets along several state highways (Oregon State Highway Department, ‘A Study of One-Way Routings on Urban Highways in Oregon’, Technical Report #59-4, April 1959). In twelve small-size Oregon cities which had made these conversions, the traffic accident rate declined 24% while the pedestrian accident rate declined 38%.
Regarding pedestrians crossing one-way streets, one leading safety expert noted: ‘”Conversion from two-way to one-way street systems has consistently been found to reduce pedestrian accidents” (Dr. Charles Zegeer, University of North Carolina, ‘Engineering and Physical Measures to Improve Pedestrian Safety’, from 1988 WALK ALERT Program Guide, National Pedestrian Safety Program).
April 3, 2008 at 9:14 am
I find this “pro” for one-ways to be slightly dubious:
“Easier than 2-way streets to time stoplights (timed lights improve traffic flow and decrease idling (& therefore pollution)).”
Yes, one-way streets result in faster moving traffic. However, you have to look at the big picture. Putting one-way streets through the core of a city encourages people to drive through the core. The actual volume of cars is higher. If driving THROUGH the city was not as easy, people would tend not to choose that option. Two-way streets coupled with decent transit and cycling options would result in fewer car trips altogether. So the net environmental effect could be positive in the sense that, while idling is increased, a lot fewer cars are actually running their engines.
A sensible approach for today’s world is to attempt to reduce traffic flow by making all other forms of transportation more appealing to users. Dedicated bus lanes with signal priority (or preferably rail), sane and safe bicycle routes and pedestrian friendly design: all of these are just as important as the argument over one way/two way.
Perhaps one ways can be shown to result in fewer pedestrian fatalities. But perhaps the reason is that there are fewer pedestrians — because I’ll tell you from first hand experience, being a pedestrian alongside a one way street is a lot more nerve wracking than on a two-way.
The number one reason to convert to two way streets is to make the use of a car less appealing for THROUGH TRAFFIC. Through traffic has no place in a downtown core.
April 3, 2008 at 9:14 am
sorry-by reduce traffic flow i meant reduce traffic volume.