A recently completed traffic study clearly shows the issues on Yankee Valley Boulevard created by increasing traffic from new developments in Airdrie’s south and the lack of a left hand turn from northbound Sierra Springs Drive.
The absence of a left hand turn at that intersection puts stress on the only nearby north-south through road, Main Street, according to Stephen Burnell of ISL Engineering, the consulting firm contracted to conduct the study.
“Levels of service at the Main Street and Sierra Springs Drive intersections are satisfactory for the a.m. peak period,” he said. “However, during the p.m. peak, several approaches have undesirable levels of service. Specifically, the westbound thru and northbound left at Main Street are over capacity during the p.m. peak resulting in significant queues and delays.”
Staff was asked at the Nov. 16, 2015 council meeting to look into the issues caused by increasing traffic on Yankee Valley Boulevard, particularly at Main Street and Sierra Springs.
Burnell presented four options to Council for improving traffic flow on Yankee Valley Boulevard. Two involved making changes to the intersection at Main Street.
Option one involves changes to the traffic signal lights to allow two lanes of traffic northbound to make left-hand turns. Southbound traffic would have one thru and one left-hand turn lane. Option two includes adding an additional northbound left hand turn.
A third option involves adding a left hand turn lane from northbound Sierra Springs Drive onto Yankee Valley Boulevard. A fourth and final option involves adding the additional left hand turn at Sierra Springs and two left hand turns from both north and southbound Main Street.
The costs associated with each option vary from a low of $79,000 for option two to a high of $349,000 for option four.
Burnell said of the four options, only the third would be recommended by the engineering firm.
“The analysis and results indicate that the improvements at Sierra Springs would provide the best overall benefit for the City of Airdrie,” he said. “It would continue to provide benefit (when) 40th Avenue (is completed).”
The cost to make the option three changes is estimated at $239,000, according to Burnell, and would include island modifications, traffic signal pole relocations, a new traffic signal pole for the northbound left-hand turn and pavement marking modifications.
Councillor Fred Burley said he understood introducing a left-hand turn at Sierra Springs had been a “non-starter” with the Province for years. The Province has maintained any changes to that intersection would negatively impact traffic using the off-ramp from northbound Highway 2 at Yankee Valley Boulevard.
“Alberta Transportation at this point and time continues to maintain that the Sierra Springs/Yankee Valley infrastructure should stay in its current configuration,” Director of Community Infrastructure Lorne Stevens said. “What we have not had to this point and time is a lot of the analysis that has recently been provided. We have signaled to the Province that we would like to revisit this discussion in light of the work that has been done.”
Stevens said there have also been developments in traffic devices which could be used at the off ramp from Highway 2 which would help alleviate any back up of traffic that could occur from introducing the new northbound left-hand turn at Sierra Springs Drive. He said that it would be the City’s intention to work collaboratively with the Province on improvements they have planned for the off-ramp as well.
Council unanimously accepted the report for information and made a motion to pursue talks with Alberta Transportation regarding the completed traffic study and recommendations.
