California Department of Transportation
map PDF

Project Fact Sheet

Project Purpose: The purpose of the project is to reopen and permanently restore full access to the section of State Route 140 (SR-140), which was damaged by the Ferguson rockslide. Currently,
motorists use a temporary bypass route to travel this portion of SR-140. Restoration of SR-140 would eliminate inconvenient detours or extended commute times for residents, businesses, and workers in the area. Restoration of the route would also give travelers a direct route to Yosemite National Park and other destinations along SR-140.

Project Description: The California Department of Transportation (Caltrans), as assigned by the Federal Highway Administration proposes to permanently restore the section of
SR-140 that was damaged by the Ferguson rockslide. The following alternatives were considered:

Alternative R: Construct a rock shed through the rockfall debris (talus) and restore SR-140 on the existing alignment.Selected

Alternative T-3:Construct a tunnel on a new alignment, tunneling into the west canyon wall, under the rockslide, and realigning with the existing highway.

No Build:SR-140 would remain damaged and blocked by the rockslide. Temporary bridges will remain in place. This alternative would not meet the
purpose (restore full use of SR-140) and need (restore safety, security, and welfare of communities affected by the slide) of the project.

Funding Source:Federally funded through the Major Damage Permanent Restoration Program.

Project Timeline:

April 2006
Rockslide activity began within the Merced River Canyon on April 29.

May 2006
On May 28, a major rockslide covered approximately 600 feet of the highway. As a result, SR-140 was closed to traffic from 8 miles east of Briceburg to 7.6 miles west
of El Portal. The closure of the highway created severe hardships for residents and businesses in the area.

June 2006
A State of Emergency in Mariposa County was declared that expedited work on a temporary highway detour around the rockslide.

August 2006
SR-140 re-opened. Two bridges were erected across the Merced River for the emergency project to temporarily divert traffic on SR-140 around the
Ferguson rockslide until a permanent solution could be developed and built.

During 2007
The existing temporary bridges prohibit vehicles over 28-feet in length from crossing and using the SR-140 detour. As tour buses are included in this restriction, Mariposa
County continued to suffer economically due to a loss in tourism revenue. Environmental process for the permanent restoration project was underway. Alternatives were developed
and multiple studies were performed to analyze the affects of those alternatives on the environment.

November 2007
Draft Environmental Document (Initial Study/Environmental Assessment) for Permanent Restoration Project was circulated for public review.

January 2008
Comment period for the draft environmental document is concluded. Comments received indicated that the project could have a significant effect on the Merced River, which is
designated as a Wild and Scenic River. Based on those comments, Caltrans begins the process of preparing a draft Environmental Impact Report/Environmental Impact Statement.

Early 2008
A more in-depth environmental analysis begins. Based on cooperating agencies’ input and the need to minimize any effects on the Merced River, new alternatives were developed
and additional studies were initiated. The additional studies include a river geomorphology study, a recreational survey, a noise/bioacoustics study, and an updated
visual impact assessment.

April 2008
Original emergency declaration is amended. Caltrans along with cooperating agencies prepare environmental documentation to modify the existing temporary bridges and remedy
the vehicle length restriction, thereby reopening the highway to all essential traffic.

May 2008
Construction of new temporary bridges begins.

July 2008
Construction on the new temporary bridges ends. The new detour is opened.

Environmental Studies Continues.

November 2010
Draft Environmental Impact Statement (EIS)/Environmental Impact Report (EIR) was circulated to public with six build alternatives.

January 2011
Comment period ends for the draft EIR/EIS. Comments received from agencies and the public indicated a strong objection to any bridge alternative because of the potential impact to the Merced Wild and Scenic River.

Spring 2011
Assembly member Kristen Olsen and Mariposa County begin legislation regarding the Limestone Salamander, a fully protected species. With this legislation, alternatives R and T-3 would be considered feasible.

July 2012
The Governor signs Assembly Bill 1973 to amend Section 5050 and Section 2081.9 of the California Fish and Game Code to allow a one-time only authorization by Department of Fish and Wildlife to issue a 2081 Incidental Take Permit to Caltrans for the purpose the Ferguson Slide Permanent Restoration Project.

November 2012
Inter agency team meets and agrees to remove all bridge alternatives because of their impacts to the Wild and Scenic River and Section 4(f) resource.

July 2013
New Draft EIR/EIS is circulated for public review.

Early 2014
Final EIR/EIS is completed.

March 2015
Begin Construction on Phase 1: Talus Removal.

November 2015
Significant rockslides and rock fall at the project site.  The Caltrans Office of Geotechnical Services assessed the area and the project team decided more assessment was needed to determine the stability of the slope.  Geotechnical data to be collected and analyzed.  Work on rock shed design temporarily on hold.

Early Fall 2017
Final Assessment Report regarding the stability of the slope.

Project Completed (Phases 1& 2).