Managing frontage-road conflicts

Octavia Boulevard in San Francisco was reconstructed with frontage roads in 2003, as described here. Construction of such boulevards has been very rare in the USA since the 1920s. The intent with Octavia Boulevard was to reclaim a neighborhood which had been blighted by an elevated freeway. The effort can be considered generally successful, but I have some concerns about the design, especially as it affects bicyclists.

The several blocks of Octavia Boulevard are shown in this Google Maps view. Note the shared-lane markings in the frontage roads and the lines for right turns from the inner lanes. Such right turns require a separate signal phase to avoid conflicts with through traffic in the frontage roads. A separate phase is not provided, but rather, the frontage roads have flashing red lights, as described on page 8 of a longer document describing the Octavia Boulevard project.. Quoting:

The side lanes ought to be controlled by stop signs and the central lanes by traffic signals. Concern over this unusual arrangement (which has been shown to work just fine on Chico’s Esplanade) prompted the installation of flashing red lights at the access road intersections, which drivers have difficulty interpreting.

I find that statement confusing. Maybe the flashing lights offend the author’s aesthetics? Flashing red lights convey exactly the same meaning as stop signs. They require traffic on the frontage roads to yield to cross traffic, and also to turning traffic from the center roadways, so that traffic does not back up and block through traffic. This arrangement is reasonable when the frontage roads serve only local traffic, but on Octavia Boulevard, they serve through bicycle traffic. Through-traveling bicyclists will either be delayed by motor traffic, or ignore the signals.

That the author of the report has little concern for bicyclist convenience also is indicated by the following statement (also on page 8):

Also, the surface of the local access roads was finished in asphalt, whereas it should be some material that marks them as part of a pedestrian realm, such as concrete like the sidewalks or cobbled pavers to match the medians. This was proposed during schematic design, but never made it into construction—and ought to be corrected.

This is one example among many of new-urbanist pedestrianism compromising the design of a bicycle facility. A lane used by through-traveling bicyclists and local motor-vehicle access is not pedestrian space, it is vehicular travel space. Pedestrians need to be — and are required by law to be — attentive and yield right of way, except at crosswalks. Cobbled pavers aren’t much fun to ride a bicycle on, either.

Now, let’s look at some different examples of boulevard design — first, a clever one in Taichung, Taiwan. A long segment of the Taichunggang (Taichung Harbor Road) with frontage roads (complained about the narrowness of bus lanes, and the ocmplaint is probably one reason the lanes were later widened.

Contrast this with the San Francisco document’s complaint that the frontage roads are too wide:

Most apparent is that the local access roads are too wide—for a through-lane next to a parking lane, they were made eighteen feet wide, rather than 16.5 feet. A narrower space would have contributed more to traffic calming.

Right, calm traffic by making the frontage road more dangerous and congested –essentially, slow traffic by making motorists wait for bicyclists and everyone wait for turning traffic. On Octavia Boulevard, the local access roads are already too narrow for side-by-side bicycle/motor vehicle lane sharing. If these lanes were to serve right-turning traffic in any large volume, they would have to be even wider.

The longer San Francisco document cites a book with an interesting title:

Allan Jacobs, Elizabeth Macdonald, and Yodan Rofé. The Boulevard Book: History, Evolution, Design of Multi-Way Boulevards (MIT Press, 2002).

I haven’t read it yet but I hope to — though, as one of its authors is the author of the San Francisco document, I’m concerned that it may similarly advocate placing bicyclists in the pedestrian realm.

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