The McKinley Avenue/120 Bypass interchange now under construction is a game changer for Manteca — and Lathrop.
*Take pressure off the Airport Way corridor.
*Provide more direct and quicker access to more than 3,000 homes under — or approved — for construction in southwest Manteca.
*Significantly improve access to the city’s fledgling family entertainment zone bookended by the 500-room Great Wolf resort and Big League Dreams and as such is expected to spur further development.
*Provides an essential link for an envisioned truck route system that will connect with the French Camp Road interchange on Highway 99 to help keep most future truck traffic out of residential and commercial areas in western Manteca.
*Help open up large parcels in eastern Lathrop for individual development as well as accommodate an approved business park on the northwest quadrant of the interchange that is within Lathrop’s city limits
City Manager Toni Lundgren noted that the pluses that the interchange will create will mean a lot of positive impacts for Manteca as well as Lathrop.
The interchange work is targeted for completion next year.
The project is being funded with $12.3 million in state funds, $7 million in Measure K funds collected from the countywide half cent road and transportation tax, and well as $8 million the city has collected in growth fees for major road endeavors..
DeSilva Gates Construction was awarded the bid of $23,387,387 to build what will be the last interchange built on the six-mile 120 Bypass.
When completed there will be five interchanges with a mile between each — Yosemite Avenue in Lathrop as well as McKinley Avenue, Airport Way, Union Road and Main Street in Manteca. They are all bookended by the interchange with Interstate 5 on the west and the interchange with Highway 99 on the east.
The work is expected to be done just as ground breaks around mid- to late-2024 for the first phase of the $131.5 million revamp of the 120 Bypass/Highway 99 interchange.
The first phase of the 99/120 project will add a second transition lane to southbound Highway 99 from the 120 Bypass interchange. It also involves tearing down the existing Austin Road interchange on Highway 99 to accommodate additional freeway lanes.
The replacement overpass for Austin Road will be four lanes. It will also span the railroad tracks requiring connecting street work from Austin Road to Atherton Drive as well as a new crossing alignment for Woodward Avenue to reach Moffat Boulevard.
Manteca’s first partial
The McKinley interchange is designed as the city’s first partial cloverleaf. But in order to save money the city is opting to build the inner ramp loops at a later date.
That means the initial construction will have all left turns from McKinley Avenue to 120 Bypass onramps go through signalized intersections just as they currently do at the Airport, Union, and Main interchanges.
When the loops are completed northbound McKinley Avenue traffic will be able to get onto westbound 120 without going through a traffic signal as would southbound McKinley to eastbound 120.
It will include a separated bike path underneath the 120 Bypass that eventually will connect with the Atherton Drive bike path to provide access to Big League Dreams and the envisioned family entertainment zone.
Ultimately it will be a link in a separated bicycle pathway that loops the city going along McKinley Avenue north to connect with a path that cuts behind Del Webb at Woodbridge that crosses Union Road and ties into the Tidewater Bikeway. The Tidewater then heads south and ties in with the Atherton Drive Bikeway via Industrial Park Drive and Van Ryn Avenue.
The McKinley Avenue interchange is also part of the long-range circulation plan for Manteca south of the 120 Bypass where more than 60 percent of the city’s population is expected to be by 2040.