POST FALLS — There are about 500 miles of roads, 20 traffic signals and 14 roundabouts in Post Falls.    

City staff are fine-tuning their transportation projections from now through 2045 before having the data analyzed by consultants and presenting highlights at a second open house for the public’s feedback. 

The Post Falls Transportation Master Plan serves as a guide for roadway needs over the next 20 years.

Post Falls civil engineer Rob Palus said in the more than two decades he’s lived in the city, Post Falls has grown to nearly 50,000 residents from about 20,000.

Viewing projections through 2045, he believes he may even see it double for a second time.

“There could be 30,000 people up by Highway 41 who don’t live there today,” Palus said.   

After the first transportation open house in November, residents were asked to fill out a survey to capture a better snapshot of problem areas for transportation.   

Working with the Idaho Transportation Department and Post Falls Highway District and sharing data with the Kootenai Metropolitan Planning Organization, the plan builds on past data along with future projections.   

“Between now and 2045 we’re going to be right around that 100,000 population mark if we continue to grow at the rate we’ve seen over the past 20 years and a plan like this sets us up for what needs to be done to handle that traffic and what it costs,” Palus said.  

A priority for the city is the Prairie Avenue corridor over the next decade or so. 

Last year, the city added a multilane roundabout on Prairie Avenue between Spokane Street and Chase Road to add to the flow of traffic through that area since it's been identified as a priority in the near future in the current master plan.  

The Transportation Master Plan also sets up impact fees to handle the cost of those roadway updates.   

Growth projections would require about $100 million in impact fees to fuel projects over the next two decades.   

“That's a lot of work,” Palus said.    

If growth is slower than the projections, there will be less money for transportation upgrades, but that also means fewer projects needed to keep up.  

This year, the city didn’t take on any road impact fee projects to better focus on the master plan.   

When completed, the 2025 Transportation Master Plan will cover traffic modeling, the public experience, public transit, regional connectivity and bike/pedestrian use. 

In the last 10 years, the traffic system has changed significantly with one of the most notable elements being the increase in roundabouts.

In 2014, there were about four roundabouts. Six have gone into use in the last two years, bringing the total up to 14.    

By city estimates, a new roundabout costs more than $1 million and a traffic signal costs around $1 million.

According to data from the Insurance Institute for Highway Safety, roads who switched to a roundabout system from traffic signals or stop signs experienced dips in injury crashes of about 75% and reductions in all crashes by about 40%.

On several occasions, public input about traffic congestion has positively affected the outcome of a project, including the ITD's Interstate 90/Highway 41 interchange.  

“The initial design was good. Public input helped change it drastically, but made it a better project in the end,” Palus said.