Cyclist riding towards Silver Lake on the Glendale Hyperion Bridge. L.A. City analysis predicts that bike lanes are feasible as part of the planned bridge retrofit project. Photo: Sahra Sulaiman/Streetsblog L.A.
As the saga of the Glendale-Hyperion Bridge retrofit project continues, it becomes clearer that, even under the city’s car traffic growth assumptions, it will be viable to add bike lanes to the new project and to keep two sidewalks.
The story thus far: In 1927 the City of Los Angeles completed the Victory Memorial Viaduct spanning the not-yet-concreted Los Angeles River. The historic bridge is, today, better known as the Glendale-Hyperion Bridge, because it facilitates the merging of Glendale Boulevard and Hyperion Avenue.
Over a decade ago, funding became available for bridge retrofit projects. Glendale-Hyperion was just too lucrative for bridge consultants to pass up. The historic viaduct is technically a six-bridge complex, so it is eligible for six times more money than an ordinary bridge. In 2013, city staff and their consultants pressed for a wrongheadedly dangerously high-speed highway-scale design. Cyclists, pedestrians, and local leaders organized visible vocal opposition to the city’s proposal. What had looked like a done deal began to appear shaky.
To its credit, the city responded by forming a Citizens Advisory Committee. Earlier this year, the city returned to the committee with multi-modal design options, including bike lanes, sidewalks, and crosswalks.
In a recent presentation [PDF] to the advisory committee, the city showed the results of its technical studies analyzing how various potential bridge configurations can be expected to perform.
The graph above shows past car traffic volumes measured on the bridge.
Graph showing car traffic volumes 2001-2014 on the Glendale-Hyperion Bridge. Image via L.A. City Citizen Advisory Committee Presentation [PDF - see page 4]
Even according to the city’s characterization, “traffic volumes have been flat since 2001.” During this period, nationwide per capita car mileage declined. Nationwide overall total car miles driven also declined. Locally, car traffic on the Hyperion portion of the bridge, the lower green and purple lines on the above graph, also declined. But call it flat for now.
The city’s experts used “historic data” and other factors to predict the bridge’s car traffic in 2040. With car traffic flat for over a decade, one might assume that future car volumes would continue their observed flat trajectory. No. The city’s fortune tellers predict a worst-case scenario showing 1 percent annual growth. Apparently, in the 2030s, people are going to drive like they did in the 1980s. As transit planner Jarrett Walker states, “This isn’t prediction or projection. This is denial.”
These sorts of predictions generally justify widening roadways which squeezes out space for pedestrians and cyclists.
The city ran its car traffic prediction models. Models based on “Level of Service,” in which the words “safety,” “walk,” and “bicycle” do not appear. LOS models keep predicting that widening freeways will reduce surface street traffic and improve air quality. Though the State of California is in the process abandoning LOS, it remains in wide use.
Even with an imaginary 1 percent annual car traffic growth for the next 25 years, a 3-lane road diet option performs slightly better than all other scenarios studied, including the bridge’s current 4-lane configuration. Right now on Hyperion, there are four car lanes, two in each direction. A road diet would eliminate one
southbound northbound car lane, and add bike lanes. Read more…