Oct 01

Thoughts on Highway 47 – Part One

Note as of 12/4/2014: This post was originally written during my run for Forest Grove City Council during the 2014 General Election.  It does, however, cover currently active developments with Highway 47.

The situation with Oregon Highway 47 is one of the two major transportation issues facing Forest Grove, along with our severe lack of east-west connectivity. The current “flashpoints” of this particular stretch of road are the intersection with Verboort and Purdin Roads, just north of the city, and the intersection with Fern Hill Road and Maple Street on the south end of the city. Both intersections have had safety issues for a number of years, and the recent tragedy at Verboort/Purdin serves an unfortunate reminder of this.

With continued growth in Forest Grove, especially on the north side, we will be faced with increasing conflict between regional mobility and local access on this critical highway. Consequently, some community leaders and city officials have commented to the effect that Highway 47 is transitioning toward becoming an “urban highway”, and the matter of what to do with the highway is currently being contested by the city, Washington County, and ODOT. Additionally, as I will show in this policy post, this matter is actually very interconnected with our startling lack of east-west arterials, as Verboort Road and Fern Hill Road actually serve as segments of alternative routes to our single east-west arterial, the perennially-congested Oregon Highway 8.

As has been well-documented in the media, the city has been fighting to get a signal at the south “flashpoint”, the Fern Hill/Maple intersection. This intersection is the main point of access to Fern Hill Wetlands, an increasingly popular nature park, and per the city’s comprehensive plan, the Taylor Way Area, right near that intersection, is presently planned for future industrial development. Additionally, for many Forest Grove residents like myself, who presently have to commute to or through the southeastern parts of Washington County that aren’t easily accessible from here (i.e. southern Beaverton, Tigard, etc.), Fern Hill Road is increasingly used as one leg of that journey, as shown on the map below.

A route some take to reach South Beaverton, Tigard, and vicinity from Forest Grove, of which Fern Hill Road forms the first leg. (click to enlarge)

This situation is effectively déjà vu of the Sunset/Beal intersection on Highway 47, shortly after the northern bypass opened in 2000. The intersection, at that time, was simply a two-way stop, just like Verboort/Purdin and Fern Hill/Maple are now, and it had an even worse safety record during the short time it existed with that configuration. ODOT drug their feet in installing the signal, despite the accident toll mounting, and regular urging from the city and county. In the case of the Fern Hill/Maple intersection, the city was told that the speed limit was too high for the intersection to be signalized (despite the fact that there are plenty of other signals on state highways with 55mph speed limits, which have improved safety). Subsequently, the city’s recent appeal to the state Speed Zoning Board to get the supposedly necessary speed limit reduction was denied.

My personal take with this situation is that the city went a bit too far with their proposed reductions, by extending the 45mph zone all the way to Elm, and having a 50mph zone between Elm and B. Things like reducing speed limits in violation of ODOT’s authority under ORS 810.180 and 811.111—including the widely-derided attempt to lower a stretch of Pacific Avenue to 20mph in 2010 (an attempt in which many current city councilors played a role)—likely did not endear our city to ODOT’s speed zoning personnel.

Personally, I support the idea of installing a signal here, at least in the short term (I’ll have more on the long term in a subsequent policy post), but oppose the speed limit reduction, for reasons I will explain in the next part of this policy essay.

Relating to the subject of speed, that brings us to the north end, at the Verboort/Purdin intersection. I still remember, as a young newspaper delivery boy in April 1997, when Scott Thunem, whose family was a customer along my route, was killed at this intersection, trying to make that dreaded left turn off Verboort and onto Highway 47 southbound—the same exact turn that everyone killed at that intersection has made. In the 17 years since that accident, all ODOT has done to that intersection is “token” fixes that have, in many cases, actually made the intersection worse, and I believe that the plans they currently have will only continue this trend.  To conclude this write-up, I will detail the changes ODOT has made thus far, and how they’ve actually contributed to the problem.

1) Widening Highway 47 to Add Turn Lanes (2005)

In 2005, owing to the fact that crash data showed that the accidents at the Verboort/Purdin intersection involved turning motions, ODOT completed a project which widened Highway 47 to add turn lanes. The highway received left and right turn lanes onto Verboort/Purdin in both directions, and Verboort and Purdin received channelized right-turn lanes onto Highway 47. The issue here, which is really symptomatic of ODOT’s mishandling of this intersection, is that they dealt with the wrong turning motions. As I mentioned before, every fatality at the intersection since 1997 has involved a vehicle turning left off Verboort.

The addition of the turn lanes greatly exacerbated the issue, by making it harder for traffic entering from the Verboort and Purdin approaches to see if there is through traffic on Highway 47. In particular, most of the turning traffic off Highway 47 is drivers coming from Forest Grove making a right turn onto Verboort. There is often such a steady stream of it that it conceals the faster through traffic that is headed northbound, creating a blind spot. A lesser blind spot exists with traffic coming from Banks, turning left onto Verboort.

Furthermore, in the process of widening the highway, ODOT removed all the illumination at the intersection and, inexplicably, didn’t replace it until after the 2007 accident that resulted in the death of 16-year-old Kaylee Tawzer of Banks.

2) Speed Limit Reductions (2007, 2014)

Following the 2007 fatal accident, in addition to the long-overdue illumination replacement, ODOT decided to make a couple of token “fixes”, including putting a flashing light on the “+”-intersection signs before the intersection (despite an ODOT project engineer claiming that replacing the overhead flashing beacon that existed before the 2005 widening “really doesn’t make a difference”), and reduced the speed limit on the entire stretch from Verboort/Purdin to the Porter Road/Oak Street intersection from 55mph to 50mph. The theory, of course, was that if a motorist coming off the Verboort/Purdin approaches got caught by the aforementioned blind spot, caused by the turn lane project, that there might be slightly less chance of another fatality in the resultant collision, due to Newton’s laws of motion.

Obviously, the accident this past spring, which unfortunately claimed the lives of Pacific University freshmen Kiden Dilla and Ayan Osman, showed that this was not the case.  ODOT did the same thing over, dropping the limit on a short stretch by the intersection even further, from 50mph to 45mph.

45 mph sign placement with worker

Getting it wrong once again (photo by ODOT)

As someone who uses this intersection several times per week—as many Forest Grove residents do—I’ve personally felt less safe at the intersection with each subsequent speed reduction. Coincidentally, the reason for this is actually the same reason ODOT won’t reduce the speed limit on the south end of Highway 47.

It’s been a “best practice” in highway engineering for many years to set speed limits on roads to correspond to the 85th-percentile speed, the speed at which 85% of traffic travels at or below, rounded to the nearest 5mph increment1—for all intents and purposes, the general speed of traffic. This particular figure has been determined by many years of research to strike the perfect balance, by reducing the amount of speed variance amongst motorists, ensuring very high compliance, and minimizing potential for speed traps.

This practice is used by most transportation departments in the United States, including ODOT, albeit there are cases where safety records, pace speed data, and other factors (including political pressure) may lead to a speed limit lower than that ideal 85th-percentile. Per page 10 of the powerpoint presentation ODOT did in the wake of the 2007 accident, the actual 85th-percentile speed of traffic on Highway 47 at the time was 63mph for northbound traffic, and 62mph for southbound traffic.  The original speed limit, 55mph (which is currently the maximum allowed by state law on non-Interstates, per ORS 811.111), appears to lie at about the 65th-percentile on the graph.  50mph is at about the 20th-percentile, while no vehicles were traveling at a speed below 47mph.  I’ve extracted the graph, which can be seen below.2

ODOT 2007 Speed Investigation Graph for Highway 47 at the Verboort/Purdin intersection

ODOT 2007 Speed Investigation Graph for Highway 47 at the Verboort/Purdin intersection

Provided compliance with the prevailing speed limit, the reductions ODOT made would theoretically reduce the force of the impact in a collision, but by getting farther and farther away from that ideal 85th-percentile speed, it increases the variance in travel speed. If the 85th-percentile speed is 63mph in a 55mph zone, the difference between someone going the speed limit and someone going the 85th-percentile is 8mph. Drop that speed limit to 45mph, and now you are looking at a 18mph differential. With such a variability, it becomes more difficult to determine the closing rate, and thus, whether or not it’s safe to enter the intersection.

With the reduced visibility created by the widening project, and the increased variability of travel speeds along the highway, creating a situation in which it is more difficult to determine when its safe to enter, these “fixes” have actually made the Verboort/Purdin intersection more dangerous.

3) Warning Signs

Finally, the most recent “improvement” at the Verboort/Purdin intersection has been the installation of rumble strips and four new “Through-Route Activated Warning Signs” (TRAWS) on Highway 47, just before the intersection in either direction. They appear as shown below (photo from ODOT):

warning sign on OR 47

ODOT’s Through-Route Activated Warning Sign System  (photo from ODOT)

The signs are activated when a vehicle coming from Verboort or Purdin approaches the intersection, which subsequently trips a loop detector, causing the beacons on the TRAWS to begin flashing. The problem with the TRAWS, however, is that yet again, ODOT is addressing the wrong problem. The problems are with the Verboort/Purdin approaches, not the Highway 47 approaches. Furthermore, with the high traffic volumes and queuing that regularly results at the stop signs on Verboort and Purdin, the beacons are almost constantly flashing, completely blunting their effectiveness. ODOT spokespeople, including Steve Harry in 2007, have previously claimed that people would “ignore red lights” should a full traffic signal be installed. Which begs the question: what makes them think motorists will pay more attention to the TRAWS devices, especially considering the issues I have highlighted with that system?

Slowing down traffic on Highway 47 won’t solve the problem of cross-traffic misjudging when it is safe to go.  Increased speed differentials for highway traffic actually make the judgement call that much harder, and unless the decision making process is simplified, these types of collisions will continue to happen, especially as traffic volumes increase.

As you can tell by my tone–a tone that I will carry over to subsequent parts of this policy essay series–I am quite critical of ODOT, as I don’t believe they understand Forest Grove’s traffic patterns.  I’ve heard the same concern echoed by many Forest Grove residents with whom I’ve talked.  As any Oregonian should, I want ODOT to succeed and be the best state DOT in the nation.  But even with the funding challenges and other issues they face, their handling of Highway 47 has been downright schizoid, and they’ve been headed down the wrong path on this stretch of road for at least a decade.

In order to right the situation, we need someone on the city council who can speak the language of ODOT and Washington County LUT, in order to get them onto the same page, and make Highway 47 and other vital roadway corridors into high-quality roads that truly serve our needs.  How many current city councilors or council candidates can give a cogent summary of the 85th-percentile rule?  That level of understanding and attention to detail with technical matters is what I hope to bring to the city council.

In the next policy post, I will detail my thoughts about what ODOT and Washington County currently plan to do with the northern segment of Highway 47, around the Verboort/Purdin intersection, my thoughts on the long-term plans for both the north and south segments, and some surprising findings about intersection safety records.



1 Depending on the policy of the authority setting the speed limits, and other factors pertaining to the nature of the road, sometimes the posted speed will be rounded to the nearest 5mph, and in other cases, the standing practice is to round it upward to the next 5mph increment.

2 As you might notice in this diagram, ODOT actually lists the highway number as 102, not 47.  That is because ODOT actually uses two separate numbering systems–the route number system (where the 47 designation originates), which corresponds to the signs you see on the road, and the highway number system that ODOT uses for internal purposes (where the number 102 comes from).  It is only with the advent of numbered routes that were first signed after 2002 that the internal highway number will match (Highway 103, the Fishhawk Falls Highway, is such an example).  The actual signed Highway 47 includes portions of three separate “internal” numbered highways: Highway 110 (Clatskanie to Mist), Highway 102 (Mist to Forest Grove), and Highway 29 (Forest Grove to McMinnville).

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  1. Thoughts on Highway 47 – Part Two » Alexander LaFollett for Forest Grove City Council

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