The City of Yelm will continue to prioritize completing the Yelm Loop and Southern Loop projects, along with creating additional infrastructure throughout the city, such as backroads and sidewalks in order to alleviate traffic through Yelm.
Yelm Public Works Director Cody Colt outlined the city’s projects over the next couple of years during a Yelm City Council meeting on Dec. 3.
Colt said traffic throughout downtown Yelm could be alleviated with the construction of more interior backroads, or connecting roads, like the work that’s been done on Mosman Avenue in recent years. He added that the city needs to continue prioritizing the Yelm Loop project, which has been in the works for 30 years and counting.
“The mayor and all of you have done a great job at this, but we need to continue pressing the legislature to construct the Yelm Loop,” Colt said. “If all of these trips through the city [are people who aren’t] from Yelm, the loop is going to divert them through Yelm.”
He added that he’d like to see the city continue to work on the Southern Loop project, in addition to upgrading local infrastructure of sidewalks and street parking. The city recently added a parking lot near City Hall and has plans of constructing one way couplets in the near future.
“If we can add sidewalks and let people walk places that live in Yelm — traffic is less effective when you can walk to the places you want to go to or park in a nearby parking lot,” Colt said.
He also discussed traffic impact analyses (TIA) and why businesses need to conduct them. He said a TIA can always be requested but is required for commercial development and housing for 24 or more units. He noted that a TIA includes a detailed analysis of nearby intersections and proposed potential impacts.
Colt added that TIAs are reviewed by an independent, third-party organization unrelated to the project. If an impact is shown to an intersection, Colt said the developer will often have to pay for improvements. Colt said, for small businesses such as mom-and-pop shops that might not be able to afford a TIA, it would be beneficial for them to conduct a trip generation report, instead.
“A bunch of traffic engineers put [a trip report] together with thousands of case studies that show what kind of trips can be generated based on the square footage and similar uses,” Colt said. “Say I wanted to come into town and open a Wendy’s, I could look at this manual, and it says I will generate about five trips per 100 square feet — that’s just a number. It’s not accurate. If I’m building a 1,000-square-foot building, I now know I’m generating 50 new trips. I can use that and do that as a cookie cutter from this manual or do a full blown TIA because I don’t agree with what the manual is saying.”
Colt used Berry Valley Road, recently rezoned by Yelm City Council, as an example. The road features three intersections, and Colt presented a graphic that displays how many times a right turn, a left turn or no turn is conducted there.
He said the nearby townhomes will generate 13 right turns at Tahoma Boulevard and two right turns at the Berry Valley Intersection, according to predictions from the traffic impact report.
“It’s showing all of these trips generating, and it’s showing all of the impacts. You can see inbound, they’re going to have 64 vehicles per hour from 4 p.m. to 6 p.m.,” Colt said. “This is used by modeling traffic engineers that know that this is what it generates with this many apartments. 64 would be driving into this site per hour, while 38 would be leaving this site per hour between the hours of 4 p.m. to 6 p.m.”
Colt added that the details from the TIA would be sent off to a third party, and if they agree with the numbers presented, businesses conducting the TIA would pay traffic facilities charges for the number of trips generated.
“Say Tahoma Boulevard is generating so many trips that this intersection failed, meaning cars can’t make left turns or the delay gets too long. The way an intersection fails is if a delay gets too long,” Colt said. “They’d have to do an improvement to that intersection. Either one, build something that can make those trips no longer fail, or two, build another road so these trips no longer fail and they’re not waiting as long.”
