Roundabout proposed for Clearwater Junction

SEELEY LAKE – The Montana Department of Transportation Project Team for the Clearwater Junction Intersection met with the public virtually and at an in-person open house Nov. 18 to share and gather feedback on the proposed alternatives, the evaluation process and the proposed solution. Installing a roundabout was the only alternative of the six evaluated that met all five criteria and is the preferred alternative. MDT is now entering the design phase of the project. While the timeframe has not been formalized, construction is not expected to overlap with the Salmon Lake Reconstruction Project.

MDT has been evaluating the intersection of Highway 200 and Highway 83, commonly known as Clearwater Junction. Clearwater Junction is a major connection point for Helena, Missoula, Kalispell and the small towns in between. The Highway Safety Improvement Program identified the busy intersection as needing improvements to alleviate traffic and safety concerns. Not only is it a thoroughfare for industrial, recreational and local traffic, it is the access point for a rest area, weigh station, the busiest watercraft check station in the state and a convenience store.

"There is a lot going on at this intersection," said Bob Vosen, MDT's Missoula District Administrator. "We need to make sure we are coming up with the right solution for the area."

The Project Team shared that traffic has increased more than two percent per year over the last five years. At this rate by the summer of 2045, summer months could yield as many as 12,000 vehicles per day. Traffic backed up on Highway 83 during peak holiday travel is also a growing issue.

The project team said that between 2003-2019, there were 35 crashes reported at the intersection, 22 resulted in property damage only, 12 resulted in injuries and there was one fatality. Of the 35 crashes, 44 percent occurred in the summer, 37 percent occurred in the winter months and 20 percent occurred during the spring and fall combined. These statistics indicate there are significant safety concerns at the intersection all year long. Heavy traffic and lack of traffic control may be a significant factor in the number of crashes.

The Federal Highway Administration created a process called an Intersection Control Evaluation (ICE) to help assess the best alternatives for improving intersections. The Team identified five ICE criteria to evaluat the alternatives for Clearwater Junction:

• Does the alternative improve safety performance?

• Does the alternative improve operational performance?

• Does the alternative consider pedestrians, bicycles and other users (such as large trucks, campers, etc)?

• Does the alternative fit in with given characteristics and context?

• Does the alternative address the project purpose and need?

The six alternatives evaluated included:

• Enhanced stop control: This could include a flashing light, additional warning sign or turn bays.

• Traffic Signal: This would require traffic to stop on Highway 83 and wait for the light to turn green before it could proceed. It requires that drivers obey the law to mitigate the safety concerns.

• Relocation/Realignment: This could include simply shifting the weigh station entrance further west to unclutter the busy intersection or a more aggressive realignment of the highways around the existing businesses. This would create out-of-direction travel and additional turning movements. It would also require significant right-of-way acquisition and the cost to the taxpayers would be much greater.

• Continuous Green T: This provides separate lanes for westbound through traffic on Highway 200 and another channelize lane for left-turning traffic from Highway 83. The land receiving traffic from Highway 83 eventually merges into the through traffic downstream. Because this alternative really only applies for three-way intersections, it would require relocation of the weigh station and rest area entrance. It also does not address the eastbound left turn conflicts.

• Restricted Crossing U-Turn (RCUT): All through traffic from Highway 83 turns right and then the left turning traffic makes a u-turn using the designated lanes to travel back in the intended direction. It would require additional right-of-way acquisition and construction impacts as well as creates out-of-direction travel for a high number of vehicles that would be using the roadway.

• Single-lane roundabout: This would provide one-way, counter-clockwise traffic circulation and a mountable truck apron for larger trucks. This was the only alternative that met all five ICE criteria making it the preferred alternative.

The Team said roundabouts have proven to reduce fatal crashes by 90%, reduce injury crashes by 70% and has an overall crash reduction by 37%. This occurs because the geometry and design of the roadway forces drivers to slow down and the circular travel reduces the likelihood of right-angle crashes. It also allows traffic to flow.

Members of the public asked several questions during the virtual presentation. The questions are bolded with the response following.

Timeline for the project?

Jacquelyn Smith, preconstruction engineer for MDT, said the formal timelines has not been established yet but she expects it could be several years before they will be able to begin construction. The project is a priority for the safety program and funding has been allocated. Now that the preferred alternative has been identified, they will begin the design. As soon as the design is done, it will be programmed and delivered through construction.

What will the speed limit be coming into the roundabout and how far back will the speed be reduced?

Speeds will be dropped from highway speed through a sequential order of speed zones 500 – 1,000 feet before entering the roundabout. Highway speeds will drop to 45 miles per hour (mph) and then to 25mph. The roundabout has an intended speed of 15mph. Exiting the roundabout, vehicles can immediately begin accelerating back to highway speeds.

"When we add a roundabout it is not even so much that we put the speed limit signs with the roundabouts. There is a long entrance of curb and gutter with a raised median and then the road will curve. It forces the driver to be able to traverse the curve and the tighter curve at the roundabout," said Project Manager April Gerth. "The geometrics and design of the roundabout, not necessarily the signs, will cause all the people entering from the four legs to be at pretty much the same speed which is really what creates the safety assistances, the low speeds and there is no huge difference in the speeds coming in and utilizing the roundabout."

How does the mountable lane handle snow?

Gerth said snowplows just work from the inside out, pushing the snow off the apron, into the driving lanes and onto the outside.

How will this project affect the weigh station?

Gerth said she doesn't know. During the roundabout development, they will conduct an analysis with input from truck drivers and managers of the weigh station to determine a better way for the roundabout to serve the traffic from the entrance and exit to the weigh station. Because the roundabout changes the way the weigh station is functioning and the way it is used, they can use funding to revise the weigh station.

Why not just reduce the speed limits and add speed bumps?

Vosen said MDT does not get compliance with speed limit signs therefore the safety isn't addressed. Research indicated that to get people to slow down, there must be visible and physical indication that requires them to reduce their speed. Warning bumps are not feasible because of the snowplows hitting them.

How does eastbound Highway 200 traffic turn into the gas station with a roundabout? Would that result in a left turn immediately after exiting the roundabout?

Gerth said they try to move approaches around 200 feet away from the roundabout. There would likely be a left turn bay into the gas station. Another option would be to travel through the roundabout onto Highway 83 and then making a right hand turn into the gas station.

Communications Manager Kristine Fife encouraged anyone to reach out to her at [email protected] or call the project hotline at 406-207-4484 or visit the project website at https://www.mdt.mt.gov/pubinvolve/clearwater/default.shtml