bigbossman 

http://www.dot.ca.gov/dist4/document..._final_web.pdf

Summary:
This project proposes roadway widening to provide standard shoulder width, and curve correction,
in a rural portion of Alameda County on State Route (SR) 84, between Alameda Creek Bridge
(approximately PM (postmile) 13.6) and the SR-84/I-680 Separation (PM 18.0) in Sunol, Alameda
County, California. Route 84 within the project area is a state Scenic Highway. The Alameda
Countywide Bicycle Plan has identified this segment of Route 84 as a proposed Class III Bikeway.
The current facility is a winding two-lane, undivided, conventional State highway consisting of
multiple horizontal and vertical curves.

The purpose of the project is to incrementally improve safety on Route 84 within the project limits
by improving sight distances, providing refuge for errant vehicles that might otherwise cross the
centerline, providing means of warning drivers who may approach curves at unsafe speeds or
whose vehicles may stray over the center or fog lines, and providing a safer traveled way for
bicyclists. Although the accident rate within the project area is below the state average, the number
of fatalities has been higher than the statewide average.

The project will widen the existing highway by up to 18’ to accommodate a 2’ soft median barrier,
one standard 12’ lane in each direction, and standard 8-foot shoulders. To make room for widening,
the project will construct five retaining walls upslope from the highway where hillsides are cut
away, a total of 5,300 linear feet of wall, and nine retaining walls downslope from the highway
toward Alameda Creek, a total of 3,400’. At the creek locations, 10-foot wide shoulders with
metal-beam guard rail will be constructed on the side of the highway adjacent to the walls. A
preferred project alternative has been identified that does not include widening at several sites in
the project area, generally at sites where historic structures are present.