Manteca — when Mayor Gary Singh and fellow council members along with other dignitaries cut the ribbon to open the McKinley Avenue interchange next month — will have done something no other California city of under 100,000 has done this century.
And that’s complete three major interchange projects, including two done with lion’s share of the cost being funded by the city.
It started with the replacement interchange at Lathrop Road and Highway 99 that was completed in 2012.
It included completing the transformation of the Union Road and 120 Bypass interchange in 2020 as the first diverging diamond interchange in California.
And it will be marked Wednesday, June 12, with the Mckinley ribbon cutting for what will be the fifth interchange along the 6-mile stretch of the 120 Bypass.
That’s three new or revamped interchanges opening within 12 years at a cost in excess of $85 million.
And the city is just getting started.
On Monday, July 17, the groundbreaking for the first of three phases involved in the $154 million Highway 99/120 Bypass/Austin Road interchanges will take place.
That will address two more interchanges, bringing the number to five.
Meanwhile, the city is in the process of funding preliminary work to repeat the diverging diamond redo at Union Road including the separate pedestrian crossing for the 120 Bypass at Airport Way and Main Street.
The first of the two projects to break ground is expected to be Airport Way.
Singh’s goal is to see the three additional projects completed within the next 10 years.
If that happens, the city will have had a role in seven major interchange projects in 22 years with an overall tab in excess of $300 million.
The first phase of the 120/99 work includes more than $8 million in city funding to allow the replacement overpass on Austin Road that would also bridge Moffat Boulevard and the railroad tracks to be widened to four lanes.
The balance of the first phase funding has already been lined up. Work includes adding a second transition lane from the eastbound 120 Bypass to southbound Highway 99.
When the first phase is completed in two years or so, the funding is expected to be in place to add a second transition lane from northbound Highway 99 to the westbound 120 Bypass.
The third phase will require Manteca to secure much of the funding.
It involves long expensive braided ramps to restore access to northbound Highway 99 from Austin and access to Austin Road from southbound Highway 99.
Because the Austin Road and 120 Bypass/Highway 99 interchanges are so close, access for traffic going to and from Austin Road from the 120 Bypass requires ramps to start for such movements far away from the interchange.
It is needed to avoid traffic slowdowns, congestion, and reduce the potential for accidents.
As an example, it will require the off-ramp for eastbound 120 Bypass traffic heading to Austin Road to start just past the Main Street on ramp.
The ramp will then need a separate bridge structure to cross Moffat and the railroad tracks. As it curves alongside the transition lanes to Highway 99, another ramp for northbound Highway 99 traffic seeking to exit at Austin Road will start at a point between the Yosemite Avenue and 120 Bypass interchanges on the Highway 99 corridor.
Those two ramps will braid somewhere between the 120 Bypass and 99 interchanges to allow access to both northbound and southbound Austin Road.
Given the ramps will open up a large swath of southeast Manteca to development, the city is pursuing a benefit district to fund the city’s share of the project.
The third phase will also include the widening of the Bypass from Highway 99 to Airport Way to six lanes with the potential for transition lanes between interchanges such as the one on either side of the Union Road interchange.
https://www.mantecabulletin.com/news/local-news/ribbon-cutting-mckinley-interchange-june-12-groundbreaking-120-bypass99-work-july-17/
