The Kellogg project, inching along for years like bumper-to-bumper traffic, moved through one of its most complicated design phases Tuesday.
A design for the section that includes the East Kellogg entrance to the Kansas Turnpike and Webb Road won approval from the Wichita City Council.
The project is complicated because the turnpike and Webb road are less than a quarter-mile apart, with not enough room for two complete interchanges. The area also serves hotels, homes and Hawker Beechcraft.
The design has a six-lane Kellogg running under a turnpike access road and under Webb Road, returning to grade level a quarter-mile east of Webb.
Continuous one-way frontage roads will be built on either side, and signals will be added at the turnpike and Webb interchanges.
The design process included 31 meetings with property owners and one public meeting since 2007, as well as meetings with turnpike and Kansas Department of Transportation officials, said Jim Armour, city engineer.
The city rejected plans to use a U-turn and roundabouts to guide traffic to the East Kellogg turnpike entrance, as well as a proposal to add traffic signals on both sides of the turnpike access road.
A plan to close the East Kellogg turnpike entrance and instead improve the interchange at K-96 about 3 miles away was nixed by the Kansas Turnpike Authority and the Kansas Department of Transportation.
The approved design will add $10 million to the project to construct the interchange at the existing turnpike entrance.
Eastbound Kellogg traffic wishing to exit at Webb will go through a signal at the turnpike interchange and proceed to a light at Webb.
Traffic on Webb wishing to go westbound on Kellogg will be able to do so without having to stop at a light at the turnpike interchange, unless the future growth of traffic requires a signal. It would enter westbound Kellogg at Cypress.
No date has been set for the start of construction. The council's action authorized $25 million for right-of-way acquisition and relocation of utilities.
The city could start buying property along the route by the end of the year, but it doesn't have enough money to build the project. The total cost from Cypress, just east of Rock Road, to 127th Street East is $300 million.
The new design is intended to handle traffic growth in the Kellogg and Webb area for at least the next 30 years.
Armour told council members that traffic on Kellogg will grow from 43,000 vehicles a day near Webb to 129,000 by 2040. Traffic on Webb will grow from 25,000 a day to 33,000, he said.
Council member Paul Gray questioned those numbers and wondered if the project isn't being "over-engineered" to meet projections that might not pan out.
"That's an extremely impressive growth rate. I don't see where all those people are going to come from, unless everybody abandons Wichita from Oliver to downtown eastward," Gray said.
Armour said that even if those traffic projections aren't realized in 30 years, the city has to build a project to last at least 75 years. "We want to be able to build a capacity at least to that design number, whether it makes it in 30 years, or 40, 50, 60 years," he said.