Alhambra Valley Road Realignment – West of Bear Creek Road

Alhambra Valley Road Realignment – West of Bear Creek Road

The purpose of this project is to restore two-way traffic and allow unimpeded traffic flow along a segment of Alhambra Valley Road, which has been functioning with one-way reversing traffic due to existing creek bank erosion at the south side of the road. A portion of the eastbound lane has been closed off with concrete k-rail and stop signs have been installed on both sides of the partial lane closure. The entire length of the project is approximately 800 feet, while the erosion along the project section is approximately 100 feet long. The roadway configuration prior to the bank erosion were two 11-foot wide lanes with minimal paved shoulder in both directions. The project consists of realigning the roadway slightly to the north, away from Pinole Creek, and reconstructing the road with two 10-foot lanes and two 4-foot shoulders. There is an existing earthen ditch located along the north side of the road that will be re-established parallel to the new alignment. Following the project, the k-rail will remain and end treatments will be installed or a guardrail system will be installed as necessary. No tree removal or trimming will be necessary. Clearing and grubbing of vegetation along the north side of the road will be necessary to construct the new alignment. Appropriate Best Management Practices (BMPs) for protection of environmental resources will be implemented during construction. Utility adjustments or relocation may be necessary in support of the project. One lane will be open during construction activities; road closure may be necessary for a brief period. If a temporary road closure is needed, advanced notification will be provided to the public and local authorities. Emergency vehicles will have access at all times. To allow one-way reversing traffic during construction, the existing stop signs will be permanently removed and replaced with temporary traffic signals at the project limits. Real Property transactions, including right-of-way acquisition, may be necessary in support of this project. Construction is anticipated to begin in fall 2020 and take approximately two months to complete.

Contra Costa

Unincorporated