Movements

Why are the separated, free right turns being removed? 

The elimination of the existing free right turns provides a safety benefit to non-motorized users in the intersection. Removing these free rights takes out two crossing points for pedestrians and bicycles.  Both of these movements tend to be higher speed because of the nature of highway to highway free rights and drivers are looking for gaps over their shoulder in traffic rather than obstacles in front of them.

Additionally, the  new right turn only lanes and signal modifications at the Y don’t automatically turn these into stopped movements when brought to the intersection. The traffic signal will be set up to run a Right Turn Overlap. This means when the large left turn movements have a green light, the right turn will also have a green light. This will happen for both the left turns from southbound Wyoming 22 to eastbound Broadway and for left turns from eastbound Broadway to northbound Wyoming 22. The right turns will have increased green time over what the free right turns are experiencing with traffic gaps today.

Why eliminate left and straight movements out of Buffalo Way?  Can't you just change the timing of the light so we can still go straight onto WYO 22 or turn left from Buffalo Way?

The proposed project at the Y is intended to enhance the operational efficiency of the intersection and minimize the delay or wait times now experienced by motorists.  At certain times of the day, and at other peak seasonal times, traffic is backed up at this intersection.  This is the primary reason for this project; to minimize the long lines of cars that wait for a green signal.  Right now the Y cycles with four phases: (1) Eastbound & Westbound Broadway, (2) Eastbound & Westbound Broadway lagging protected left-turns, (3) Southbound WYO 22 only to allow for heavy left-turn movements, and (4) Northbound Buffalo Way only onto WYO 22. 

As time is granted to each phase, the other legs are at a stop to allow for the conflicting traffic to clear.  The lane configuration on WYO 22 (single left and shared thru-left), do not align and are conflicting movements with Buffalo Way. This does  not allow for them to run simultaneously. This is unlike your ideal 4-way intersection, like a plus (+) sign, where northbound and southbound movements can potentially run simultaneously.  This saves time.  At the Y intersection, basically every leg of the intersection gets its own isolated time, forcing 3 other legs to wait their turn, causing backup and congestion. 

It is difficult to increase efficiency if adding time somewhere takes time away from another leg and the geographic layout of the intersection does not allow for simultaneous north to south  movements. Eliminating the time allotted to one of the legs opens up time for other movements.  Since northbound Buffalo carries the least traffic, and has reserve capacity, it was the best choice. 

Current summertime peak hour traffic volumes at the Y are:

• 272 = Northbound Buffalo Way
• 710 = Southbound WYO 22
• 1061 = Eastbound Broadway
• 1216 = Westbound Broadway 

Buffalo Way is competing to occupy the intersection against approximately 3000 other vehicles who are at a standstill.  With each cycle, Buffalo Way is granted approximately 15 seconds to clear, while all the other three legs wait.  Buffalo Way is underserved and has reserve capacity, whereas the other three legs are reaching their limit and if nothing is done to address this, gridlock will be reached in the near future,  about 12 years.   If more time is provided to Buffalo Way, the wait times and backups on the other three legs will increase and gridlock will be reached much sooner.

With the proposed operational improvements of adding dual lefts on Eastbound Broadway and through-left turn movements taken from Buffalo Way, more vehicles will be served,  allowing  the intersection to clear, and reducing overall commute time.  The time that was allowed for Buffalo Way will be redistributed to the other legs, with a net decrease in wait times of about 14 seconds per cycle.  This is one less phase than existing.

Isn't this new configuration unsafe?

On the contrary, this project was funded through our Safety Program as a benefit of minimizing the left-turn crash potential.  The cost-of-crash experiences exceed the cost for the improvement, which had a favorable benefit to cost ratio.  As compared to other similar signalized intersections, the Y has a higher crash rate, and this is due to the oversaturated traffic volumes, minimal available gaps in the traffic stream and high crash potential, especially during the evening rush hour. 

The elimination of the existing free right turns also provides a safety benefit to non-motorized users in the intersection. Removing these high-speed free rights takes out two crossing points for pedestrians and bicycles. Both of these movements tend to be higher speed because of the nature of highway to highway free rights and drivers are looking for gaps in traffic rather than obstacles in front of them.  Bringing the right turn movements to the intersection will slow the turning movement and help to improve the overall safety of the intersection. 

Won't this have a negative impact on side roads like Scott Lane and Maple Way?

According to projected traffic volume increases, the intersections of Broadway Ave with Maple Way and Scott Lane will reach an unacceptable level of service in 20 years (Maple Way) and 14 years (Scott Lane), without any modification to The Y intersection. With the estimated redistribution of traffic from the changes proposed with this project, this unacceptable level could be reached approximately 4 years sooner.   However, the intersections of Maple Way and Scott Lane will more than likely perform better than predicted, due to the conservative approach that was taken in modeling.

It is also worth noting that there will be signal improvements that will occur at the intersections involving Maple Way and Scott Lane as part of the reconfiguration project. WYDOT will be replacing the signal detection at all three intersections with Wavetronix radar detection.  Wavetronix is a state of the art system that allows more dynamic signal timing and should further improve efficiency and reduce delays at the intersections.

Why only a temporary fix?

This will not be the final fix for the Y intersection, but it gives WYDOT the time to plan appropriately and conduct a more in depth review of all alternatives.  That process can take a significant amount of time and will involve not only the Y intersection, but the entire WYO 22 corridor to Wilson. With the proposed improvements above, the intersection will operate satisfactory for approximately 16 years.  This proposed improvement will remain as a temporary improvement until the final ultimate lane configuration and intersection alternative can be determined for both WYO 22 and Broadway corridors.