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SR 99 Auxiliary Lane - Chico

What is the Project?
In order to improve operations and safety on State Route 99 from State Route 32 to East First Avenue, the Butte County Association of Governments (BCAG) and the City of Chico requested the California Department of Transportation (Caltrans) to complete a Project Study Report (PSR) in November of 2000 investigating alternatives for constructing a number of improvements on State Route (SR) 99 and East First Avenue in the City of Chico.  Improved operations and safety together with reduced congestion are the goals of the proposed project.
Proposed operational and safety improvements would primarily consist of adding northbound (NB) and southbound (SB) auxiliary lanes on SR 99 between SR 32 and East 1st Avenue interchanges, the widening of SR 32 on and off ramps and East 1st Avenue on and off ramps.   Included in the widening for the East 1st Avenue NB off ramp would be the provision for dual left turn lanes to facilitate the turning movements of existing northbound traffic to westbound traffic on East 1st Avenue and the widening of East First Avenue.

In November of 2001, BCAG took the lead to develop the environmental document and begin the process of completing the first phase of this project which is the Project Approval and Environmental Document (PA&ED) phase.

Why was the Project developed?
The necessity of this project is driven by operational and safety considerations.  As much of the local public is aware, this short section of roadway is subject to delays and difficult merging and weaving conditions during the AM and PM peak hours.  It is also host to accidents ranging from minor collisions to resultant fatalities.

The California Highway Patrol office on 995 Fir Street was contacted in early September of 2001 with the intention of getting a general idea of the number of accidents occurring on this stretch of roadway.  For a reporting period of January 1, 2000 - July 31, 2001, this office had processed 1113 accidents throughout their entire jurisdictional patrol area.  The area generally encompasses and includes the following:

     State Highway 99 from Tehama County to State Highway 149
     Route 191 from the Paradise Town Limits to State Highway 70
     State Route 32 from the Sacramento River to Forest Ranch
     Pentz Road from the Paradise Town Limits to State Highway 70
     The Skyway to Butte Creek
     All roads west of State Highway 99 to the Sacramento River

299 of all 1113 reported accidents in the Chico office's jurisdiction occurred on State Highway 99.  95 of those 299 accidents (31.8%) were on the stretch of roadway being addressed by this project.

Project Completion

Phase 2 and 3 Construction
Phase 2 and 3 were completed in one project and involved the construction of the northbound SR 99 on and southbound SR 99 off ramp from and to SR 32, the northbound and souhtbound auxiliary lanes and the northbound SR 99 on ramp to East First Avenue. A retrofit widening and gap closure of the viaduct structures traversing Bidwell Park together with Palmetto structure widening and gap closures was completed in 2015.  The project also constructed soundwalls in both the northbound and southbound directions of SR 99.   

Project construction began in the fall of 2011 with the California Department of Transportation as the construction manager and was completed in late 2014.   

To date, all structures have been completed, with soundwall and retaining wall construction and ramp improvements almost complete. Traffic control and other measures included to reduce impacts to the public during construction are in place.  Inconveniences at various points in time will continue through 2014 with completion expected by the end of 2014.  

Questions or comments:
Should you have any questions or comments regarding the project please call the Caltrans Public Information Office at 530-741-4572.