Traffic signals lights are timed to allow the heavy traffic movements to have longer timings than those with less traffic volumes.
The City is looking at having a traffic signal upgrade started this year as part of the wireless program that would improve and coordinate signal timings in the CIty.

This question also applies to the set of lights on Wapiti Road by Northern Metallic, Bank of Montreal. Why advance lights for only 2 of the 4 directions of traffic flow? This causes some major backups & some risky turns by some impatient drivers. Just a matter of time until somebody gets seriously injured or killed.

Not every leg of every signalized intersection gets an advance green arrow. There has to be enough vehicles making this turn movement at peak time in order to warrant these turns. Although some intersections in town have these that aren't warranted or becasue of the vehicle detector location they may get an advance turn for a smae amount of vehicles. The City is now has timing standards based on Canadian Standards. This is so we can move the legs of the intersection with the most traffic in an efficent manner. As we upgrade the traffic signals the intersections with non warranted advance turns will be adjusted accordingly.

Perhaps a traffic count is in order? Have you been @ that intersection during peek hours lately? It gets very backed up heading east/west especially the turn lanes. I don't think the amount of traffic using the Westside business park was estimated high enough.