On ‘Congestion Ahead’ signs, cut-through traffic, and speed limits

Reader board warning of congestion on westbound Hwy 26 just before the Sylvan exit. (Photo: Lisa Caballero/BikePortland)

I don’t have much reason to drive on Highway 26 anymore, now that I no longer have a dog who requires regular grooming. So I can’t tell you how long Oregon Department of Transportation’s reader board has been warning about congestion. But happily for drivers, the warning is actionable. If you are heading downtown, it is placed just before the Sylvan exit. What fool wouldn’t cut through local streets to avoid back-up at the tunnel?

ODOT installed its first Dynamic Message Signs (DMS) less than a decade ago after studying how the technology worked in other cities. What they learned was that the reader boards significantly reduced the number of crashes in those cities, and could hopefully improve Portland’s “unpredictable commute times.A 2014 Oregonian article mentions that they would also give drivers “a chance to choose an alternate route.”

Street classifications map from ODOT transportation GIS. Annotated by BikePortland.

The “choosing an alternate route” part is becoming a bigger issue now with congestion pricing schemes under discussion and with neighborhoods worried that toll avoidance will lead to more cut through traffic on local streets.

Portland Bureau of Transportation’s (PBOT) response to area traffic has a push-me-pull-me aspect to it. Over the past few years, the bureau has installed traffic calming along several cut-through routes. At the same time, however, it has also maintained the speed limit on those residential streets at 25 mph, even though the streets lack bike facilities or sidewalks in many places.

Hikers scurry across SW Marquam Hill Rd at their trail crossing. The street is posted 25 mph despite lacking sidewalks and its classification as a “local” street. (Photo: Lisa Caballero/BikePortland)

Even on select local streets, PBOT has taken exception to its “20 is Plenty” speed reduction program and maintained a 25 mph posted speed. Where do you find those hand-picked exemptions? On the route from the Sylvan exit to OHSU: Marquam Hill Rd and Gibbs St.

Fairmount to Gibbs is the only route for people riding a bike or walking to campus from the neighborhoods to the west. Yet, as BikePortland recently reported, PBOT’s Development Review department ruled against a new development building sidewalks on its SW Gibbs Street frontage.

Maybe there is something like this going on in your neighborhood too. It is sure to become a more important concern as congestion pricing rolls out. But we aren’t starting from neutral. The purpose, in part, of these reader boards appears to be to encourage cut-through routing. And PBOT seems to be accommodating it with higher speed limits in some places.

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Scott Kocher
3 months ago

Legally speaking, I remain baffled that PBOT leaves ANY local service or collector (i.e. “non-arterial”) streets in residence districts posted at faster than 20 MPH. There is a law and ordinance that dictate.

cc_rider
cc_rider
3 months ago

I don’t have ‘congestion ahead’ signs in my neighborhood but every weekday afternoon has hundreds of motorists driving down the N Central “greenway” to avoid Lombard. Lots of Washington plates blowing stop signs to cross N Central too. Super dangerous.

Somehow people are managing to ignore the beg barrel telling them to please go 15mph. What would have thought it?

ROH
ROH
3 months ago

As long as the streets are wide and it feels safe driving fast, people will continue to do so. That article about Helsinki and the narrowed lanes should be informative for city leaders. If you want less speeding then prioritize design that makes speeding harder. It is unrealistic to assume people will go the speed limit when the street “tells” you you can go much faster

cc_rider
cc_rider
3 months ago

N Willamette is a living testament to how little Portland cares about road safety and VisionZero. After Jason Barnes was killed by a speeding motorist, zero action was taken to slow motorist down on the street. I go through that intersection a lot on foot and I’d say 1 in 20 motorist stop for predestrians and maybe 1 in 10 aren’t speeding.

D2
D2
3 months ago
Reply to  cc_rider

Agreed, this feels like a conclusion in search of a cause. The ‘Congestion Ahead’ signs are for safety. A freeway should flow at high speed, when a section of it often does not a warning for people is a good idea.

I have gotten off 26 to use side streets before, but my information has always come from checking traffic beforehand, via an app, or just looking ahead a bit on a hill or curve and using logic to say “oh, that looks way worse than usual”.

axoplasm
axoplasm
3 months ago

By the time ODOT warns me of Congestion Ahead, my phone has already picked an alternate route! I remember the Bad Old Days when Waze was directing drivers up fun little streets like Chesapeak or La View

If we want to make cut-throughs unenticing, the design of side streets is the place to do it. Chicanes, diverters, plantings, dead ends. Make it a hassle to drive more than three blocks in a straight line.

Ironically southwest has a head start on unenticing side streets, with twisty narrow roads, bad sight lines, limited alternatives and ambiguous use of space (no sidewalks!). At this very moment there’s a backup in the tunnel — Google maps tells me it’s 11min from Sylvan to OHSU via 26, 12min via Scholls/Patton/Broadway, and 14min via Humphrey/Fairmount/Gibbs. Yeah that’s 14min where I’m not stuck in stop-go traffic (which is a bargain I would take TBH) but my apps probably won’t direct me that way.

Chris I
Chris I
3 months ago
Reply to  axoplasm

Wait, you would spend an extra 3 minutes and burn more fuel to avoid some traffic on the freeway?

rick
rick
3 months ago
Reply to  Chris I

There should be a toll put on that OHSU cut-thru. What other apartment projects are prohibited from sidewalk construction in Portland or even Multnomah County besides that new one on Gibbs?

axoplasm
axoplasm
3 months ago
Reply to  Chris I

It was intended as a joke (haha) but I do really hate freeways

squareman
squareman
3 months ago
Reply to  Chris I

I used to take back roads all the time before navigation (used my Thomas Guide) just to avoid stop-and-go freeway traffic. It was mainly a great way to avoid the stress of it all and the road rage of others, even if it took significantly longer (and wasn’t in a hurry). Bonus: it became a great way to discover many hidden secrets about all those side roads: tiny little businesses and restaurants I would patron, magnificent vistas I’d pull over at, and better intuitive understandings with the “lay of the land” in the region. The side roads I was taking were generally more rural or remote and not neighborhood streets.

These days, I just avoid driving altogether if I can. If I must, I avoid peak hours as best I can. And when considering a new job – the commute matters. If I can’t do it via mass transit or bike, I’m not as likely to take the job. At my worst, I had a 54 mile commute (and where a lot of these exploratory trips came from). That was madness.

Doug Hecker
Doug Hecker
3 months ago

Yeah, I’m not sure advocates were thinking when they wanted congestive pricing, especially when ODOT’s answer has mostly been, “take other roads.” Quite frankly, as PBOT reduces roads for other types of uses and forms, I’d much rather like the traffic to be on the freeway tbh. Maybe the city can toss up a Congestive Toll on Flavel Dr, Johnson Creek, or 82nd to match what ODOT is doing lol. At some point, we have to think about the dynamics of these asks and the little jingle that gets tossed around for Joe C.

Ethan J
Ethan J
3 months ago

if speed limits are lowered, drivers won’t care. The solution is to make these roads hostile to cars. Introduce speed bumps to slow cars down. Narrow the lanes to lower the margin of error drivers have. If a bus goes through, increase the frequency of buses, both increasing the chance to get stuck behind them, and encouraging riding.

Strictly enforce speed limits with a radar and place RFID tags license plate stickers so authorities can identify you even if you hide your license plate.

Ethan J
Ethan J
3 months ago
Reply to  Ethan J

Actually no, that could be easily abused by PPB, stalkers, etc (but it’s not like they couldn’t get that data from Google Maps/Waze/Your insurance company).

Mark McClure
3 months ago

Lisa, please forgive me for taking liberty with the title of your article. Here is a snapshot of a sign I took in 2014 and again in 2019. The sign always got me to slow down. Also, see the comment I added to my 2019 snap.