2016/10 – Portland

Portland is a city of two million residents with a 6% bicycle mode share. The city estimates that its cycle infrastructure has so reduced spending on gas use, congestion, healthcare and conventional transport, that it saves it $2.6 billion per year.

Hawthorne Bridge

Each day, cyclists take 20,000 trips across four bridges spanning the Willamette River.The Hawthorne, built in 1910, is oldest of the four bridges.

Originally fitted with two 6′ sidewalks, they were widened to 10′ in 1999. Bike traffic tripled in a decade that followed. By 2015, daily bike trips averaged 6300 — the highest known use for any bridge crossing in the U.S.  However, this welcome growth of use would degrade the Hawthorne’s “level of service” to a D – Poor.1

5858643115_fedb2d7b1e (1).jpgHawthorne Bridge. Image: Flickr CC.

Tilikum Crossing

In 2015, the Tilikum Crossing came on line, just south of the Hawthorne, at a cost of $135 million.  The Tilikum comprised a 31′ wide transit way for light rail and buses – plus two 14′ paths for biking and walking. The Tilikum soon handled 2600 bicyclists per day, drawing down bike trips across the Hawthorne by 25%.  B – Good.2 3

Tilikum_Crossing_-_bicycles_4 9.42.56 PM.jpgTilikum Crossing, Southern Span, Portland, 2015. Image Tedder.

George Washington Bridge

Contrast this with the GWB, which in 1989 first allowed bicyclists to access its 7 foot wide South Path. Paralleling the rise of biking in the region overall, bike trips averaged 3700 per day by 2015 – with a corresponding decline in the GWB’s level of service.  F – Failing.4 5

screen-shot-2015-04-09-at-10-18-14-am.jpg George Washington Bridge.  Image Hassan Diop.

Nor will the situation improve under the PA’s current plan to allocate to cyclists a single 7 foot path as part of a $1.9 billion restoration, because if bike trips continue to grow 10% per year, there’ll be 9000 cyclist crossings a day by 2025.  F – Failing.6

cab178-amman-whitney1-1Port Authority’s Plan for GWB, 2024.  Image Amman and Whitney.

Given what Portland has done to promote smart transportation, and reap the benefits, one can speculate would they’d do with the facility. Tolerate the continued erosion of service, or seize the opportunity to improve it?7

Screen Shot 2016-10-24 at 10.41.12 AM.pngSource, Seattle DOT and NYC DOT.

Neile Weissman, 2016


Notes and References

– To be consistent with GWB data recorded by NYCDOT, traffic counts for all bridges use the months of October, 2014 and April, May-June, July, August, September, 2015

– Seattle DOT adds 25% pedestrian trips,  pro forma, to Hawthorne and Tilikum bike counts.

– Hawthorne-Tilikum traffic counts were weekdays. On the GWB, weekends.

[1] Hawthorne Bridge, 2015 – Federal Highways Administration Shared Use Path Level of Service (FHWA SUPLOS) grade of 2.90/D – Poor: Nearing functional capacity. Peak-period travel speeds are likely reduced by levels of crowding. More users will significantly degrade bicyclist LOS. Some users likely to avoid peak-period use.  6293 bicyclists per day on (2) 10′ paths.

[2] Tilikum Crossing, 2016 – 3.95/B – Good: Path maintains a high-quality LOS for bicyclists. Retains significant room to absorb more users.  2599 bicyclists per day on (2) 14′ paths.

Screen Shot 2016-10-21 at 10.28.21 AM.png

[3] Hawthorne Bridge, 20163.30/C – Fair: Meets current demand and provides basic service to bicyclists. Modest additional capacity available; however more pedestrians, runners, or other slow-moving users will begin to diminish bicyclist LOS.  4692 bicyclists per day on (2) 10′ paths.

[4] Cyclists fault limited use of the George Washington Bridge, NY Times, 1987, http://tinyurl.com/jccqbhq

[5] George Washington Bridge, 2015 – 1.71/F – Failing: Trail conditions significantly diminishes the experience for bicyclists, and most likely all, user groups. Significant conflicts should be expected. Does not effectively serve most bicyclists.  3699 bicyclists per day + 25% ped-runners (actual) on a single 6.75′ path.  Or, 417 bicyclists and 107 peds-runners per hour in 2015.  Data source NYCDOT.

[6] George Washington Bridge, 20241.94/F – Failing.  9034 bicyclists per day + 5% peds-runners (projected) on a single 6.75′ path. Or, 417 bicyclists per hour in 2015 * 10.43 * 9 years = 1018 bicyclists per hour.  Presume 5% “pedestrian incursions” on the bicyclists’ path. 1018 * 1.05 = 1069 users per hour in 2024.

[7] Since 1991 Portland has increased the amount of people who travel to and from the central city via the Hawthorne Bridge by 20%, almost entirely by bicycles. If car trips had increased at that rate, we’d have widespread congestion, toxic pollution, and a more urgent need to make costly investments into the bridge and adjacent roads and ramps. – Bike Portland