Pecos Road and 17th Ave Intersection

[ Update 3/1/2015 see story Changes coming to Pecos Road in next 4 to 6 weeks ]

This is all pursuant to the death of competitive cyclist Highly Falkner on Pecos road near the intersection with 17th Ave in November of 2013… Sorry this is somewhat a stream-of-consciousness…

Also see updates on issues via facebook: Pecos Action Group

Pecos Road is a (major?) arterial road, in particular this deals with the section in the City of Phoenix. It is unusual compared to other major arterials in the area, it functions more like a rural separated highway. It has two through lanes in each direction, seperated by a wide median. There is limited cross traffic. Over the years the major intersections got traffic signals chronolically from east to west: 40th Street, 32nd Street, 24th Street, Desert Foothills Parkway. 17th Ave does not have, and may never get, a signal as the traffic volume drops the further west you go; and Pecos dead-ends just about a mile west of 17th Ave.

There is NO bike lane on Pecos Road; there is a relatively wide, generally very good surface, paved shoulder. Many bicyclists and hikers/joggers use the shoulder, it is a popular recreational area.

The posted speed limit is 50mph, again, that’s unusual for the area, the other major arterials in the Ahwatukee area (of Phoenix) are 40mph (some may be 45??).

The way the intersection was prior to 2013

[google maps street view circa 2011] This is a ‘T’ intersection, with 17th Ave terminating at Pecos. Pecos had two lanes in each direction with a shoulder stripe (“edge line”) discontinued a small distance before. In the street view you can see where they tried to black-out some of the striping, which used to actually bend around the corner and continue north on 17th Ave. The right lane was a combination through and right turn lane. There was no special bicyclist accommodation; westbound bicyclists tended to ride on the shoulder, and needed to beware of 1) right-turning traffic (a “right hook”); 2) oncoming left turning traffic (a “left cross”); and 3) drive-out traffic from 17th ave.

It may be that Pecos used to end at 17th Ave? I just can’t remember but that would explain the blacked-out striping that was still visible in the 2011 google street view; and the oldest street view, 2008 shows the blacked-out, ground-up curved lines even more clearly. So sometime prior to 2008, Pecos used to terminate at 17Th Ave.

Motorcyclist Fatality / New 2013 Striping

In April 2013. A motorist drove out from the stop sign at 17th Ave into the path of a westbound motorcyclist, killing him.

It is apparently this fatality, along with probably complaints from residents that used 17th Ave,  that caused a major re-striping which was completed something like June 2013.

I believe the goal was to concentrate/channelize the very high-speed Pecos traffic, so that it would be less likely drivers turning left from 17th Ave would mis-judge the westbound Pecos traffic. Furthermore, eastbound approaching 17th Ave was changed so that the left lane became a left-turn-only — this meant left turners from the 17th stop sign have a free-flowing left; once they cleared the westbound traffic. The pre-2013 configuration eastbound had both two through lanes and a left turn pocket.

[google maps satellite view of newer, post 2013 striping]

In words the westbound (the direction of interest for our purposes): beginning about 800′ back from intersection, the right lane was marked with diagonal arrows pointing left; the shoulder stripe (edge line) was discontinued at 600′ back, then there was a “mixing zone” of about 150′ where right lane traffic must either merge left if going through, or right into a newly formed right-turn only lane. It is intended in this mixing zone, that cyclists that were formerly using the shoulder that are going straight through merge left. Then for the last 450′ there’s a bike lane (possibly not designated; may also be referred to as a bike buffer) the rest of the way to the intersection which lies between the general through lane, and the right-turn only lane.

This arrangement is problematical for bicyclists because of the high speed merging, especially so far back from the intersection; traffic speeds (see below) are routinely above 70mph (posted 50mph).  It is also bad because inattentive (including sleeping, impaired, or whatever) drivers in the right through lane who fail to “mix” will be aimed straight into the rear-end of a bicyclist in the bike lane (or bike buffer).

Traffic speed / counts / speeding?

This info was provided by Kerry Wilcoxson of City of Phoenix Streets Dept:

Apparently, the speed data that is in the “Traffic count” documents above isn’t reliable (it’s very high; e.g. the 85th percentile speed e of 17th was about 85mph!).

The radar based speed data showed the eastbound vs. westbound speeds to be very close, and the 85th percentile speeds in morning-time, at 57-58mph, to be a bit slower than the afternoon-time, at 61mph. The posted speed limit is currently 50mph all the way from the 202 ramps (where Pecos turns into a limited-access) and 17th Ave. If i heard/remembered correctly, the posted speed west of 17th Ave (i.e. the last mile) drops to 40mph.

There appear to be a huge speeding problem. E.g.  nearly 30% of 4,000 vehicle/day on Pecos were  going 20mph or more over the posted 50mph limit. How many violations have Phoenix PD handed out, say over the past year? Everyone knows speeding is a safety problem; but everyone also knows you can’t change motorist behavior simply by posting speed limits (more about that later). Humans are by their nature, scofflaws. That being said…

There are many many many speeding infractions,  §28-701, being committed by drivers along Pecos Road. Almost a million per year, allowing a more than generous “buffer” over the posted limit (the math is the average speed at 70th percentile is 68.9mph; so 30% of 7755 cars/day are doing 18mph or more over posted limit).  How many speeding citations have been written? Perhaps approximately 0.0000% have been cited? Would speed enforcement have saved Highly Falkners life? We’ll never know.

Also, speaking of speed, I was under the mistaken impression that any 20-over was by definition criminal speeding §28-701.02…. that’s not quite so, in fact the relevant section is it’s a violation to “Exceed the posted speed limit in a business or residential district by more than twenty miles per hour”. As far as I understand, this area would not qualify, because it is neither business or residential.

Public Review (Feb 25)

In a second public info meeting at Pecos Community Center, Kerry W unveiled plans and answered questions. Here is what I gleaned about the plan; to be implemented in the next couple of months at a cost of estimated $60,000 to come from a neighborhood safety budget:

  • (westbound) will go back to two through lanes; i.e. as it was prior to 2013; in other words, it will be two lanes with no dedicated turn lane. The buffer zone (the region between what was the left/through lane and the RTO lane) goes away. Eastbound configuration is unchanged.
  • The westbound posted speed limit will decrease from 50mph to 45mph 1500′ west of Desert Foothills Parkway. The posted speed limit west of 17th Ave had already been 40mph. (that doesn’t sound right, but I think that’s what i heard?). The eastbound posted limit will be unchanged at 50mph.
  • What is currently just a shoulder will be designated bike lane (ground symbols and r3-17 signs will be installed), both east and westbound, beginning/ending just west of Desert Foothills Parkway, and ending at the western terminus of Pecos Rd (the cross street is oddly enough Chandler Blvd.)
  • The westbound bike lane at 17th Ave will get a solid-green treatment (in particular, it will be thermoplastic; which is supposed to last far longer than paint). For the engineering-curious:  the colored pavement is allowed due to  what is known in engineering circles as an “Interim Approval”  —  Optional Use of Green Colored Pavement for Bike Lanes (IA-14) from the FHWA.
  • solar powered radar speed boards, one in each direction, will be installed. These have some sort of data-collection capability.
  • A couple of street lights will be added to improve illumination near 17th ave.

See story Changes coming to Pecos Road in next 4 to 6 weeks .

Review of Options (held in January)

Thanks to Joe Struttman and Brandee Lepak (and anyone else i missed) for working with Kerry and organizing a review; and especially to Joe for graciously inviting us to his home for a review of the printed large-format diagrams provided by Kerry.

A couple of really promising developments, regardless of what re-striping is ultimately chosen; this is encapsulated in “Kerry’s comments” above.

The city of Phoenix will lower the westbound (not sure about eastbound? speed limit between Desert Foothills Parkway and 17th Ave (and possibly all the way to Chandler Blvd, where Pecos ends) to 40mph. This is huge! And is a coup for traffic safety. Supporting that change is…

A westbound “lane diet” where the right lane if completely dropped and traffic in the right lane is forced (through some physical device/poles/scallops/rumble strips or whatever) into one lane, the existing left lane. It is well understood that simply lowering a speed limit will not lower motorists’ speed. Funneling to one lane will: in a single lane, the prudent driver sets the maximum speed.

The lowering of the limit below 50 enables the city (as a matter of policy, or something; ie. it’s not a rule or law) to *designate* a real bike lane between (at least DFP and 17th Ave).

Beyond that, there were several specific options presented involving re-design of westbound Pecos approaching 17th — the most engineering-sound was #4, which I’ll call “Road Diet and BL w/standard right-turn-only pocket”. I call it standard because it functions like MUTCD fig 9C-4 (but there is only 1 through lane). It is desirable because it forces right-turning motorists to make a conscious merge, and an unconscious motorist simply barreling straight ahead will not harm bicyclists in the BL.

There was a fifth option that liked by many, also with a road-diet, plus in this one the BL is to the far right all the way up to the intersection. It needs clarification because it was presumed it must be a right turn only lane at 17th and if that were the case there would be a RTO to the left of a BL and that’s not going to happen. (MUTCD says “Standard: A through bicycle lane shall not be positioned to the right of a right turn only lane” this is a big deal; it is not negotiable)


  • What changes, if any, would there be to eastbound Pecos? E.g. would the speed limit also be lowered? Would there then be a designated BL?
  • Any transition zone, e.g. as shown in Fig 9C-4 above, should be as close as feasible to the intersection; so the transition happens at the lowest speed possible. There is very little volume and there’s no reason for this to be more than 150′; in other words there’s no danger traffic will “stack up”
  • The “lane diet” should occur as far away from 17th Ave as possible; it should be done all the way back at DFP, 1 mile away.
  • In any design with an RTO, the “dead zone” (now painted white) should be mechanically (poles? bollards? raised bumps of some sort) reinforced to prevent “right turn lane cheaters”, those who would go straight from the RTO lane.


Other things

A traffic signal is heavily suggested/demanded by some. The traffic volumes do not “warrant” the installation of a signal — See MUTCD section [to be looked up].

Traffic signals are not a panacea; to point out the obvious, sometimes drivers violate them, and when they do catastrophe results.







One thought on “Pecos Road and 17th Ave Intersection”

  1. Regarding the radar-speed study, from Kerry: The studies are broken up into AM and PM and eastbound/westbound so there are four pages. They are typically conducted by a person with a radar gun standing as close to the travel lane as possible measuring 100 vehicles in each direction traveling alone or at the lead of a pack. The studies are done far enough away from an intersection to make sure that slowing for turns is not an issue so these should be true free flowing speeds.

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