REDDING, Calif. - As plans develop to add shopping centers to the area around South Bonnyview Road in Redding, many people who live and work in the area have expressed concerns about adding more traffic. It's an area which is already hit hard by rush hour traffic delays.
Their concerns are that Churn Creek Marketplace, already in development, along with the proposed Costco and Redding Rancheria plans will create even more problems. On top of more shopping, residential areas along Shasta View Drive and Airport Road are also expanding.
In response, the city decided to look into what could be done to alleviate concerns and help the area continue to grow. They created the South Bonnyview Road Interchange Project Study Report-Project Development Support (PSR-PDS). A staff report on the project said it will be the basis for phased improvements over the next 25 years as development continues.
The city worked with Omni-Means and Caltrans to create traffic modeling and analysis to consider different ways the interchange could be improved.
The report analyzed several different interchange layout possibilities, four of which were considered viable. Those ranged from a traditional tight diamond with traffic signals at each interchange, to a corridor with roundabouts at each intersection.
Ultimately, the preferred layout would include what is called a diverging diamond interchange (DDI) with a multi-lane roundabout at the Bechelli Lane intersection and at the Churn Creek Road intersection.
The DDI would be between the on and off-ramps from I-5 to South Bonnyview Road. It's an interchange style where lanes cross over each other, so drivers would be on the left side of the road. It allows traffic to enter and exit freeways without having to cross lanes of traffic.
The PSR-PDS had the following to say about the DDI:
"A recent Transportation Research Board study of early DDI interchanges found that collisions were reduced by 33 percent and injury collisions were reduced by 41 percent compared to the traditional diamond interchange they replaced. They have been in use since 2009 with a total of 87 operational to date in the USA, with 18 more currently under construction."
There are no such interchanges in California, though there are four in the planning or design stages.
The expected total cost of improvements would be $14,000,000 to $20,000,000 dollars, including $2,000,000 in right-of-way costs. The project, however, would be phased in over time.
The City Council said the South Bonnyview interchange is a high-priority need to help the city develop.