Next June we all know a roundabout gets going on the east end of Locust Street, a street home of a church, a church school and a major city playground. Two of the three Three Sisters streets go north from Locust along with another popular residential street, Hayward. The street slopes down slowly from east to west with a rather sharp decline approaching its west end on Pine Street with Parkside Terrace on the north corner and Callahan Park on the southside, a bus shelter on the east side perhaps about 100 feet south of the intersection. Callahan Park also continues a north/south pedestrian way for students who travel to and from Champlain School.
Somehow, Locust Street either end has intersections with major change in the last decade. But are they the right changes? And what do the changes mean to safety, particularly for pedestrians? Pedestrians remain the "apartheid mode" with few efforts at high quality safety transportation investments to benefit the pedestrian, more often than not in our urban areas a person of color.
We all walk but few bike!)
Also, somehow, the west intersection of Locust, a T junction, is largely untouched by the Champlain Parkway, either in the current controversial design (my personal feelings set aside) or the coalition promoted Champlain RIGHTway (Pine Street Coalition, Vermont Racial Justice Alliance and Fortieth Burlington, LLC [Innovation Center]). (Not to say the RIGHTway coalition of three groups are truly all ears for any grassroots suggestions!!)
While most have an opinion about roundabouts or at least know about them, few have given much thought to the City’s Department of Public Works (DPW) increasing use of RRFB’s (Rectangular Rapid Flashing Beacons) installed mostly without even bothering to do much analysis of intersection management choices. So about 2013 or early 2014 during the Mayor Weinberger administration the first RRFBs were installed along Pine Street. I call them fireflies because along Pine Street at night where there are several one sees them light up sporadically like fireflies.
In part because there is no clear priority for pedestrian safety in the City (its’s the apartheid mode remember) not much attention has been given to the RRFB versus the acknowledged safest pedestrian intersection which is the all-way-stop, versus the traffic light which is the true enemy of the pedestrian.
Defining the differences, particularly in regard to safety, is important even if one does not care about pedestrian since the City has about a third of its traffic high crash intersections, with our a quarter, 20, on the current VTrans high crash intersection list—those intersections average 1.5 injuries a year. Our five downtown VT roundabouts average one injury a decade (0 bike injuries in 52 years recorded and one pedestrian non-serious injury). Burlington experiences about two car occupants a week and one either a cyclist or a pedestrian injury (2012-2016 data).
The RRFB
The RRFB started as proprietary product and owed much of its success to a great extent from advertising and public relations activity (something roundabouts and all-way-stops lack!).
Traffic engineers for three generations have lived off traffic signals installations and their management—many without much knowledge of RRFB performance have apparently succumbed to their allure—and cheapness, about a tenth the cost of a traffic signal (about $175,000 median price).
What do we know about the RRFB? The 2008 first research mostly centered on its first use for mid-block crossings—BTV is doing this too. A more recent study, 2020 is fairly comprehensive but still centers on mid-block or mid-block with a significant private entry: https://www.oregon.gov/odot/Programs/ResearchDocuments/SPR814Final.pdf
As an aside, it would nice if DPW began to seek research and analytical support in their decision making. Too much of Burlington transportation—Regional Planning too but to a lesser extent, staff as well as consultants—remains cookbook and ignoring major changes, sometimes rapid like bicycle treatments evolution at roundabouts, now proceeding.
What we should ask and demand is transportation investments based not just on comprehensive cost benefit (sill in its infancy here in Vermont), but also on the “science,” transportation research. In a word we need a Fauci overview, the science, in our transport decisions. The 2020 Racism as a Public Health Emergency and 2019 Climate Change Emergency, both new City policies, must be afforded more than check the box response at DPW and CCRPC.
So, privately promoted RRFBs are new, little research is available, particularly on use at intersections. It is true that mid-block crossing use may have benefit cost benefits versus very expensive ($1 million on up) HAWK and Pelican treatments—which do better than RRFBs but not when benefit cost is involved—still a tradeoff of cost for pedestrian injuries which is still involves careful thoughtful decision.
RRFBs at the Locust St intersection. First, the Pine Street RRFB intersection treatments apply mostly to crossing Pine Street but not along Pine crossings themselves—i.e., Marble, Locust, Howard marked crosswalks. Second, we have no thorough research on RRFB versus the normal and equally highest level of safety all-way-stop and roundabout. We must analyze alternatives because single-lane roundabout with central islands can be quite expensive, but mini roundabouts (recommended up and down Pine Street by Dan Burden in the AARP 2014 Pine Street Workshop report with preliminary feasibility designs provided for Pine/Maple Street intersection on page 1) can be quite cheap and obviously superior in safety (and most everything else!).
Consider the fact that within the first few months of installation, there was a critical pedestrian injury at the Locust Street/Pine Street RRFB—more serious than any pedestrian injury (the one!) in a half century of downtown VT roundabouts tabulated. One critical injury does not mean we should reject RRFBs, but it jogs the mind and connects the new roundabout at one end of Locust, the mini recommendation of Dan Burden (58th on the list of great urbanists in recorded time) for every intersection south of Main Street, and, yes, the very fact the intersection has been unaddressed in the Champlain Parkway over half a century.
So, first, does an all-way-stop make sense at Locust/Pine as that is the traditional traffic engineer correctly staged most safe for pedestrians. Actually we have an all-way-stop at both Pine/Maple and Pine/King about seven blocks away—it is safe for the many pedestrians (most students using to access school buses a.m. and p.m. are persons of color). And yes, there is no anecdotal of pedestrian crashes there. But for sure anyone who travels, works, or lives along Pine Street knows at traditional drive time p.m. experience regular 4-7 minutes queues to clear the Maple Street intersection northbound. That would likely be duplicated for the downtown bound stream at Locust as well. The alternative roundabout here because of tight space, the mini-roundabout. First, Federal Highway Administration (FHWA) lists the roundabout as the only pedestrian safety “proven countermeasure” and is the only intersection type on the list—FHWA might consider adding the all-way-stop to pedestrian proven safety countermeasure list.
Yes, Roundabouts at Each End of Locust Street
Since an all-way-stop means unacceptable addition at busy intersections of more queuing with vehicle delay and increased climate heating in violation of our 2019 Climate Change Emergency policy—the roundabout becomes the default choice—which in addition to pedestrian safety equal to the all-way-stop (signals FHWA tells us generate a 20% higher pedestrian crash rate than either all way or rounds) also results in sharply lower crash rates for vehicles, reductions in climate change emissions and pollutants, drops in vehicle delay and motor fuel consumption, lower maintenance cost and not eventual replacement costs (signals have a limited lifespan, even RRFBs), improved scenic quality, and certainly some safety benefit for cyclists if only through traffic calming of speeds two-three blocks in all directions.
At Locust/Pine most of the land, at least on three quadrants of publicly owned (the Park and either City and/or Burlington Electric Department on the westside assure no right-of-way acquisition issues. So, the costs of a mini-roundabout would be low and development time a few weeks of design and public review process followed by construction in the next normal season—usually installing (like at Shelburne Street Roundabout) in June after both elementary schools are closed. Price would be mid-five figures likely. Certainly for costs, comparing mini to RRFB, the roundabout wins easily. So let’s proceed with a scoping of a mini-roundabout at Pine/Locust and provide the safest street in the City with a roundabout at either end?—for a lengthy roundabout dogbone round duo!!
RRFBs at Shelburne Street Roundabout? Why?
For some reason RRFBs are to be installed at the Shelburne Street Roundabout in spite of the fact that not a single pedestrian has every died on the 9,000 US/Canadian roundabouts on a marked crosswalk through 2020 (two deaths on marked Burlington the roughly 75 traffic signal crosswalks since1998).
If one were concerned about improving pedestrian safety at a roundabout which cuts serious or fatal injury upwards of 90% there are certainly better, cheaper engineering choices one would be expected to take. First, one could narrow entries/exits to 10 feet (see Keck Circle in Montpelier or Grand Union in Manchester Center) versus the practice of VTrans of 12-15 feet wide entry and exit lanes. In other words, reduce area of pedestrian exposure—a principle often and thankfully employed by our DPW. No costs involved but certainly some resulting reduced speeds beneficial to pedestrian safety. Second, one could employ raised crosswalks which has been done in a few cases elsewhere. Again, no cost. The problem is if you get roughly about a 90% average decline in pedestrian safety, then additional expenditures need to be carefully considered and not controversial. Narrowing entries and raised crosswalks do not engender anything negative. A signal without some scientific support? Raises serious concern the signal could increase ped injury rate.
RRFBs which are not the best practice at an intersection and where there is no science to support it, is very questionable at a roundabout (why at a roundabout, for example, but not at an equally performing safe intersection type, the all-way-stop?).
I myself avoid where I possibly can ever using an RRFB at an intersection, instead of venture carefully onto a crosswalk, making sure a vehicle driver sees me and yields, then halfway across repeat with traffic in the opposite direction. The reason? Like at a roundabout (sans signals) its safety depends not only by design (medians restricting crossing to one direction of traffic at a time, vehicle speed constraints) but also by making safe crossing include an alert pedestrian self-protecting and a driver yielding—neither with any distraction like a signal. Those are absent at a traffic signal—any traffic signal which interferes with accountability of driver and pedestrian, therefore accounting for the relatively poor signal pedestrian performance and the superior roundabout pedestrian performance.
Locust/Pine Roundabout and Bicyclists
Right now the Locust/Pine intersection provides no treatments applicable to the bicyclists. The Locust/Pine roundabout would provide significant safety improvements. First, a standard ramp—off on approach and ramp-on at the outgoing leg would be provided—same as at the Shelburne Street Roundabout. This “choice” of take the roundabout lane or shift to pedestrian mode and benefit from the safer pedestrian crossings is a safety improvement over the current configuration. The cyclist entering Pine Street from Locust clearly gains as a stop is no longer necessary, reduced speed conditions mean easier integration to traffic, etc. For bicyclists traveling south the roundabout offers an easier left turn against slowed northbound traffic and the off-on ramping now absent.
Final Note
My TonyRVT.blogspot.com includes a recent monograph application of roundabouts along North Street which is termed the most dangerous community street in Vermont and through adoption of mini roundabouts potentially becoming the safest. In addition there is the archive the monograph and walkability Burlington which first saw the light of day as a six part series here on the BWBC listserv.
Tony Redington
September 19, 2021
TonyRVT99@gmail.com
TonyRVT.blogspot.com
@TonyRVT60
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