Hwy 169 "the devil's triangle" redo delayed

MnDOT delays Hwy. 169 project

Crosstown wins out over devil's triangle

I don't have to drive this direction often and when I do it is off hours. But this section of roadways is one of the most dangerous in Minnesota

Full 57 page report (PDF)

Below is an extract with safety and traffic findings:


US 169 at 85th Avenue (CSAH 109)

From the years 2000-2002, sixty-three crashes were reported in the Transportation Information System (TIS) database at the intersection of US 169 and 85th Avenue including three “A” crashes and one fatal crash. The crash density of 21 crashes/year is twice the metro average. The crash rate for this intersection was the same as the metro average of 0.8 crashes per million-vehiclemiles, however the severity rate of 1.6 is higher than the metro average of 1.2. This intersection ranks fourth by crash costs on the statewide Top 200 High Crash Cost Intersections (Top 200) list for 2002. For the Top 200 list, a monetary value is assigned to each severity level and intersections are then ranked accordingly. The intersections on this list typically have a high number of crashes, several severe crashes, or both. Seventy-one percent of the crashes at this signalized intersection were rear-end collisions which is higher than average for urban signalized intersections.

Nineteen percent of the crashes were right angle collisions including three “A’s” and one fatal crash. Further investigation of the Traffic Accident Reports revealed that all twelve of the right angle crashes were the result of red-light running with the driver on 85th Avenue being sited for the violation in 75% of the crashes. In ten of the twelve crashes, the driver on 85th Avenue was traveling eastbound. In eight of the twelve, the driver on US 169 was traveling southbound. A cursory field review revealed a small hill in the northwest quadrant of the intersection. Removal of this hill will not prevent drivers from running red lights, but it will perhaps give drivers additional time to see an approaching vehicle.

US 169 at CSAH 81

This intersection had 119 crashes, which was the highest of the three intersections studied. The crash rate of 1.6 crashes per million-vehicle-miles and severity rate of 2.7 were at least twice the metro averages of 0.8 and 1.2 respectively. The crash density of 39.7 crashes per year is almost four times the metro average of 10.5 crashes per year. This intersection ranks third on the Top 200 list.

There is a high occurrence, almost 70%, of rear-end collisions at this intersection. Nine percent of the crashes at this intersection were sideswipe passing. Left turns into on-coming traffic and right angle collisions accounted for 14% of the crashes at this intersection. Although there were no fatalities at this intersection during the study period, 45% of the crashes at this intersection involved injury.

CSAH 81 at 85th Avenue (CSAH 109)

This intersection had 33 crashes during the three-year study period. Approximately one-third of the reported crashes were rear-end collisions. Rear end collisions are common at high-volume signalized intersections. Right angle collisions or left turns into on-coming traffic accounted for, a higher than expected, 54% of the crashes at this location. Although there were no fatalities or “A” crashes during the study period, these types of crashes are typically more severe in nature.

US 169 at Burlington Northern & Santa Fe (BN&SF) Railway tracks

There have been four train/vehicle crashes at this crossing during a five-year period in the years 1999 through 2004, resulting in five personal injuries. Of the 4,552 public at-grade crossings in Minnesota, this crossing is ranked as the most hazardous crossing in the state with a .3535 Accident Prediction (AP). The next highest AP in the state is .194. Accident Prediction was developed by the Federal DOT to identify and rank high hazard crossings. The formula calculates numerous factors to determine risk at every crossing (e.g., number of trains, AADT, train speed, vehicle speed, type of road surface, number of roadway lanes, urban/rural, etc.).

There is one through train per day on this line, with a 25 mph timetable speed, and numerous switching movements. With the high AADT on USTH 169 and CSAH 81, along with necessary switching operations by the railroad, the train/vehicle conflict is, has been and will continue to be substantial as evident in the AP and accident records.

Traffic Congestion

A traffic operations capacity analysis was conducted for the a.m. and p.m. peak hours at the intersections of TH 169 and CSAH 109, TH 169 and CSAH 81, and CSAH 81 and CSAH 109. Capacity analysis results identify a level of service (LOS). LOS is a qualitative measure that describes operational conditions. There are six levels of service, A through F, which define the full range of driving conditions from best to worst. LOS A indicates the best traffic operation, with vehicles experiencing minimal delays. LOS F indicates an intersection where demand exceeds capacity and drivers experience substantial delays. LOS A through D is generally perceived to be
acceptable by drivers. LOS E is characterized by unstable traffic flow where the intersection is operating at, or very near, capacity. The LOS calculation method used was from the 2000 Highway Capacity Manual. The LOS calculations are based on 2000 traffic data. Due to the high traffic volumes on TH 169, the first intersection “meters” the volume to the next intersection, reducing the demand at the next intersection. This is due to the high traffic demand at all three intersections. The capacity is routinely exceeded which causes substantial queuing and delay, and contributes to increased accidents. These conditions are expected to worsen if no improvements are made and as traffic volumes continue to increase.

Some business and conservative leaders favor raising Minnesota's gas tax to fund projects like this. I'm one of them!

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