Yesterday featured a quick write-up on advisory bicycle lanes, with a bit of discussion on what they are and where they could possibly go in Minneapolis. The rationale behind the advisory bike lane is to stripe a bicycle lane on narrow, low-traffic streets, with vehicles using the remaining center space and merging into the bike lane when needed to pass opposing vehicles, yielding right-of-way to bicycles in the process.
One of the key features of a street featuring advisory bike lanes, and a feature that makes the concept possible, is the lack of a yellow centerline stripe that would normally divide street traffic into its opposing directions. The Federal Highway Administration’s Manual on Uniform Traffic Control Devices (MUTCD) sets down the criteria by which a street centerline is needed or not needed. In short, the MUTCD (which has legal teeth via Federal law) requires a centerline on urban streets at least 20′ wide and with an average daily traffic (ADT) level of 6,000 vehicles or more. The MUTCD recommends (but does not require) centerlines if that daily traffic level is 4,000 vehicles or more.
Minneapolis Street Centerline Requirements, using MnDOT traffic data. Map by the author.
This map, using the latest (mostly 2012) MnDOT traffic data, is color-coded to show where street centerlines are required, recommended, or not required. Red streets have traffic volumes (at/above 6,000) that require a centerline and thus are ineligible to receive advisory bike lanes. Yellow streets are in the traffic volume range where a centerline is recommended, but not required. Green streets have daily traffic volumes below 4,000 and thus do not require a centerline. Conversely, they are potentially good candidates to receive advisory bike lanes. White streets are neighborhood streets that likely do not have high traffic volumes and would also be good candidates.
As you can see, there are several streets that could potentially be converted to include advisory bike lanes. In southwest Minneapolis, the combination of W 60th St, Sunrise Dr, and W 58th St is a potential candidate except in the immediate vicinity of Lyndale Ave. Long stretches of 4th Ave S, Bryant Ave S (already a Bike Boulevard), and Dupont Ave S could be converted. In far northwestern Minneapolis, Humboldt Ave N, Bryant Ave N, and 51st Ave N are possible streets for conversion. In Northeast, there are several streets in the area bounded by Central Ave, University Ave, and Lowry Ave that could be converted. There are also several possible conversion streets in the area between Hiawatha Ave and the Mississippi River.