Bloomington’s Death Roads

October 23, 2016 at 7:14 pm | Posted in Bloomington and Suburbia | Leave a comment
Tags: ,

There’s a danger lurking in Bloomington in the form of the ordinary looking streets you drive, walk, and bicycle on. Engineers call them “Four Lane Undivided” and you might call them nothing special, but the have another name, the Four Lane Death Road, and all the ones in Bloomington need to go. I originally wrote about this when I was writing for, and now that there’s been a pedestrian fatality in Bloomington I thought I’d revise and update it here.

A Danger to Motorists

Imagine a typical trip down a death road. You’re driving down the right lane. Pretty soon there’s a bus stopped or a brave and fearless bicyclist in the lane, so you move into the left lane. Then a car is at a dead stop waiting to make a turn, so have to move back into the right lane. But stopping in a traffic lane to turn is a good way to get rear ended, as well as causing friction and other motorists to make abrupt lane changes, another was of inviting crashes. Plus the motorist waiting to turn is going to get ancy, fearing being rear-ended if he stays their to long, so at the slightest break in traffic s/he guns it, hopefully not hitting any cars or pedestrians in the process.

Engineers like to talk about “conflict points”, where two motorist might try to occupy the same place at the same time. A four lane road doubles the conflict points at an intersection…


Conflict Points

And conflict points for turning movements. Red is through traffic and blue is turning traffic. You can see at the bottom left the red car moves out of the left lane to avoid the blue car that is stopped in the through lane to make a turn, potentially hitting a car in the right lane, then ahead could rear-end a car stopped to turn in either direction on the through lane. At higher volume intersection a right turn lane is appropriate to remove a further conflict point.


A Danger to Pedestrians

There’s really two issues with pedestrian safety on Death Roads. The first is that with multiple lanes, a motorist will stop for a pedestrian. A second car coming will not see the pedestrian because s/he is crossing in front of the stopped car and try to pass the stopped car, and hit the pedestrian. There’s been several fatalities due to this in the state recently, such as on Maryland Ave in St. Paul.

A second problem is a site distance problem with turning traffic. A car in the left lane can block the view of a car in the right lane from a motorist waiting to make a left turn.


A few months ago there was a pretty dramatic crash on 86th Street and Nicollet Ave. A southbound Xcel Energy truck made an evasive maneuver to avoid a left turning car that failed to yield, but wound up losing control and plowing into a signal pole on the southwest corner, knocking it over. And in “Final Destination” in real life, a man that was just standing their waiting for a bus was buried under the whole mess. As typical once the scene was cleaned up and the next dramatic story came about the news media stopped reporting on the investigation, so we don’t really know what happened, but I strongly suspect it was either the sight distance issue or the northbound motorist trying to get out of the through lane.


Scene of the crash on a Bloomington Death Road.

Of course this particular crash could have been prevented by putting the bus stop in a better location (and it has in fact been moved to the near side) but it illustrated the problem with Death Roads in particular, and also pedestrians are vulnerable almost the full length of Nicollet Ave due to the sidewalk being right next to the curb with no boulevard and no shoulder. It’s only a matter of time till a texting or drunk driver jumps the curb and hits another pedestrian that just happens to be there.

The situation was aggravated by the lack of a flashing yellow arrow (FYA) at this intersection. A “left turn yield on green” (YOG) just doesn’t communicate the amount of caution that’s needed for permissive left turns. Right now the the focus on convestions is to decrease safety and increase efficiency by converting protected only turns to FYA protected permissive, but we need to focus on increasing safety too by converting YOG turns to FYA, as Richfield has done at 76th Street and the northbound I-35W ramp where a freeway ramp crosses a major regional trail.Then you have Minneapolis and St. Paul, which are still installing new, dangerous YOGs, and in those cities pedestrian volume is much higher.

Bloomington even looked at not allowing left turns during a pedestrian phase. This was rejected, in part because existing controllers can’t handle this and it would have required fabricating external logic (this might be possible in the future as the trend is to have traffic controllers run custom software that is more adaptable). But one thing Hennepin County is doing now as standard practice is a 4 second delay in permissive only phases from the time the green through indication lights to the time the FYA lights. This prevents left turners from gunning it as soon as they get a FYA before oncoming traffic and pedestrians can establish themselves.

Some Conversion Options

But what if we restriped the road to three lanes? Bicyclists have a place to ride without impacting traffic. And left turning cars have a safe place to wait without disrupting through traffic. And the issues with pedestrian safety are solved.  The only downside is at traffic signals and stop signs through traffic has one lane instead of two, but often there is functionally a single lane here anyway due to stopped traffic waiting to turn.


Lyndale Ave, a former Four Lane Death Road restriped to three lanes.

Sometimes of course the roads are so wildly overbuilt the center lane is not needed because there’s so little traffic that it’s unlikely a left turning car will cause a conflict or create congestion. Here’s 102nd St near my house  with even more generous shoulders. At the heaviest volume near Lyndale Ave, traffic volume would have to triple to justify four lanes. Death Roads where traffic does not justify them create dangerous with almost no efficiency benefit.


102nd Street at Pleasant Ave.

These can of course be done within existing curb lines, but Richfield has done even better by completely reconfiguring the Portland Ave was reconstructed. In addition to eliminating the death road, there is now a protected bicycle path for the 61% of people that would be interested in bicycling but refuse to do it on a busy street, even with painted lanes.Also notice the trees and streetlights (although by my measurements the streetlights fail to meet state and national standards for an arterial street in a residential neighborhood.



Portland Ave, Richfield

Here’s a chart from Portland, Oregon: The 1% “Fearless” will ride on a busy death road and the next 7% will if there’s bicycle lanes. Richfield is to be commended for building protected infrastructure for the next 60% of their population.


Of course sometimes you simply need more than one through lane to handle motorized traffic. In that case it’s appropriate to add a 5th lane and protected bicycle infrastructure (this is what Richfield is doing with the center section of 66th St) , or maintain the death road configuration if there’s absolutely no way to widen it. Lyndale Ave in Minneapolis I wrote about earlier in the article on Traffic Signal Warrants, and that’s one situation that it applies to. But nowhere in Bloomington.

The traffic volumes that require more than one through lane vary depending on the study, with 20,000 being the most commonly cited figure nationally. In Minnesota 15,000 is the de-facto upper limit, as Mn/DOT requires a traffic study at volumes above that. The only street in Bloomington with those kind of volumes is Old Shakopee Road between France Ave and I-35W, and the houses are set back so far there that adding a turn lane and preferably a protected bicycle path could be done without impacting too many actual houses.

The Status of Bloomington’s Death Roads

Bloomington had an awful lot of Four Lane Death Roads. In a traffic calming policy started a number of years ago on collector streets, they’ve slowly been fixing them as streets come up for resurfacing. For political and possibly liability reasons they’ve avoided marking and calling them “bicycle lanes” even though they are, and they cater to the 7%. Conversions have been rarer on arterial streets, because the policy didn’t cover them and many of the arterial streets are county roads.

Here is a map of the status, Fall 2016. Black are Death Roads that haven’t been looked at. Red are Death Roads that were looked at but still not fixed. Green are Death Roads that have been converted, and Yellow are those planned or under construction. We’ve come a long way, but it’s time to do more.


A Word about “Pork Chops”

I’ll also say a few words about Channelized Right turns, aka “free right” aka “pork chop”. I’m not really inclined to blame the presence of a pork chop an Nicollet Ave and 86th St. It’s true that without one it’s possible they lady might not have been standing right on the street, but on the other hand the issue would have been easy to rectify by moving the bus stop, and pedestrian push-buttons are required to be present and be present right next to the curb due to ADA requirements so this encourages pedestrians to wait right by the street.

This particular pork chop was installed along with the 3-Lane conversion a few years ago. Turn lanes can mitigate two of the problems with such convention; you’ve double the impact of the right turning conflict points and decreased through traffic lanes at signalized intersections. This conversion was already contentious, with one of the councilmen who’s district it passed through an outspoken opponent. If problems had appeared at this intersection it would have put a screeching halt to any future conversions in Bloomington, and might even have resulted in a reversion to four lanes.

I’ll also say as a pedestrian I much prefer intersections with pork chops as opposed to without. It’s not an issue to wait a few moments for traffic to clear on the right turn before crossing, and then you have a much shorter stretch of pavement to cross on the Walk signal and you know that the car you’re in front of you is not going to not see you and start off in an attempt to make a right turn on red. Another person expressed a similar comment about liking them as a pedestrian on a recent MnPost Article.

There are ways to make them better. One way is to reduce the angle that they enter the cross street, to give turning motorists a better view of pedestrians and cross-traffic.


Burnsville has experimented with Rectangular Rapid Flashing Beacons at a Highway X and Highway 13.


Pork Chop with beacon, Burnsville.

They could even be signalized like is the practice at some places in Wisconsin.

Just because Bloomington has been improving things doesn’t mean it isn’t time to do better.

Back to North Star Highways Home


TrackBack URI

Powered by
Entries and comments feeds.