Project
Description
SR120/Union Road Interchange Project
1st Diverging Diamond Interchange (DDI) in California.
1st Diverging Diamond Interchange (DDI) in California.
The City of Manteca in partnership with Caltrans District 10 and SJCOG are working to improve safety and traffic flow at interchange located at State Route 120 and Union Road. The project will improve safety conditions by constructing new on and off ramps, widening Union Road to 4 lanes between Daniels Street and Lifestyle Street, and providing a Class I shared-use path and Class II bike lanes.
The new interchange reduces conflict points between vehicles and moves traffic more efficiently through the interchange. The DDI is unique in that traffic on the local road is shifted to the left side of the road, before being shifted back to the right. Eliminating any left hand turns through the intersection. Upgrading to the unique DDI configuration provides significant cost savings and safety benefits for both vehicles and pedestrians.
Union Road is a key crossing of State Route 120 in the City’s bicycle master plan. The new Class I path will provide a 10-foot wide grade-separated trail that eliminates all bicycle/vehicle conflict points within the interchange to provide safe and efficient passage for bicycles, pedestrians, and other non-motorized travel.
Auxiliary lanes will be constructed between Airport Way and Main Street on eastbound and westbound State Route 120 to provide for increased traffic flow during peak times.
Benefits of a
Diverging Diamond Interchange (DDI)
Diverging Diamond Interchange (DDI)
Safety is a priority. This Diverging Diamond Interchange will reduce the number of conflict points from the existing 26 down to 14. Most importantly, the more severe collision types (crossing/T-bone) are reduced form 10 down to two.
Existing overpass does not have designated pedestrian or bicycle access. The new interchange will provide a Class I shared-use path and Class II bike lanes. The new Class I path will provide a 10-foot wide grade-separated trail that eliminates all bicycle/vehicle conflict points within the interchange providing safe and efficient passage for bicycles, pedestrians, and other non-motorized travel.
Cost effective solution allows for the project costs to be greatly reduced compared to other interchange types. Also allows for the existing bridge to remain.
Improved traffic operations on Union Road. This project will construct auxiliary lanes on State Route 120 from Airport Way to Main Street.
Compact footprint by eliminating right of way acquisition.
Class I grade separated shared use path improves pedestrian and bicycle mobility. This accomplishes the City’s General Plan goal and closes a significant gap in the pedestrian network.
Safety is highly increased with a DDI due to a reduction in collision points from 26 to 14 and separate bicycles and pedestrian lanes.
Construction
Schedule
Project Schedule
June 25, 2019 | Groundbreaking Event |
July 2019 | Construction Begins |
November 25, 2020 | New DDI opens |
Project Notes
- Delays are anticipated weekdays between 6:00am – 4:00pm on Union Road between Atherton Drive and Daniels Street. Please be aware of increased truck traffic in the area as a result of the interchange improvements.
- Traffic Detours and Closures will be posted in advance on this website in the Updates Section and the City of Manteca Facebook Page.
- Work will generally take place between 6 a.m. and 5 p.m. Monday through Friday. Night and/or weekend work may occur as necessary.
Project Hotline: 209.707.3470
Project
Updates
Traffic Alert: August 17 to August 20
Two freeway night closures will take place during the week of August 17th. Crews will be removing falsework from the new bridge at Union Road over SR 120.
Freeway Night Closure Details
Eastbound
Monday, August 17: 10:00pm – 6:00am
Tuesday, August 18: 10:00pm – 6:00am
Detours will direct traffic off SR 120 at Airport Way via Atherton Drive.
Westbound
Wednesday, August 19: 10:00pm – 5:00am
Thursday, August 20: 10:00pm – 5:00am
Detours will direct traffic off SR 120 at Union Road via Atherton Drive.
Please expect delays and proceed with caution to ensure the safety of the traveling public and construction crews.
Call the project hotline with any questions or concern and a project team member will get back to you – 209.707-3470.
We apologize in advance for any inconvenience.
Big Day on SR120/Union Road Interchange Project!
July 14, 2020
Today, the contractor performed the concrete deck pour on the widened portion of the Union Road bridge.
Other recent project activities include paving on the future western ramps, and underground and electrical improvements.
Construction crew remains on track for a late 2020/early 2021 project completion, weather permitting.
Please expect delays and proceed with caution to ensure the safety of the traveling public and construction crews.
Call the project hotline with any questions or concern and a project team member will get back to you – 209.707-3470.
As always, the project team appreciates your patience!
SR120/Union Road Interchange Project Update
June 12, 2020
This week at the SR120/Union Road Interchange project in Manteca, construction crews performed the stem and soffit pour on Union Road Bridge to accommodate the necessary widening. The photo shows the progression of the bridge work and other recent improvements on the site to date.
The City is still anticipating delivery of California’s First Divergent Diamond to the public in late 2020 or early 2021. Weather dependent.
Please expect delays and proceed with caution to ensure the safety of the traveling public and construction crews.
Call the project hotline with any questions or concern and a project team member will get back to you – 209.707-3470.
We apologize in advance for any inconvenience.
Thank you,
The Project Team
CALIFORNIA’S FIRST DIVERGING DIAMOND
Construction Is Moving Forward
Another great day on the SR120 / Union Road project.
Ray Tunkel and Chris Hilton from Dewberry shown on the future bridge deck are working towards the opening of the new Diverging Diamond Interchange at SR120 and Union Road.
The City of Manteca and the whole team want to thank you for your patience and support as we diligently work to complete this project and open up California’s First Diverging Diamond for the Manteca community and area travelers on SR 120.
Stay Updated!
Project updates, road closures, and the ability to sign up for electronic notifications are available on the project website. Website also features a project description, key project elements, location map, construction updates, frequently asked questions and construction photos.
Callers are welcome to leave a message with questions, comments or concerns on the 24/7 project hotline and a project team member will return your call. Project Hotline (209) 707-3470.
Left Turn Lane Closure at Union Road and Daniels Street
Beginning June 1st and continuing until early September construction crews on the SR120/Union Road Interchange project will be closing the northbound left turn lane from Union Road to Daniels Street.
Closure is needed to provide safety to the traveling public during construction.
This temporary traffic condition is being implemented to complete important work on the project while also keeping the traveling public safe during the process.
Please expect delays and proceed with caution to ensure the safety of the traveling public and construction crews.
Call the project hotline with any questions or concern and a project team member will get back to you – 209.707-3470.
We apologize in advance for any inconvenience.
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