Alpine Road is an old regional road that used to connect the Town of Portola Valley to Page Mill Road. San Mateo County closed this road to vehicular traffic in 1979 due to road degradation and multiple washouts. Since then, there have been multiple culvert failures and washouts that have added sediment to local waterways.
The trails at Coal Creek Open Space Preserve link to Alpine Road, which serves as an important regional trail connection for cyclists, equestrians and hikers alike. In April of 2019, Midpen entered into a formal partnership with San Mateo County, and established a process to build a trail on the old roadbed.
The Alpine Road Regional Trail Improvement Project will correct the degraded roadbed and failing culverts that have led to significant erosion and sedimentation issues. The trail improvement activities and construction are anticipated to take place this summer from June to October 2022. A second construction season from June to October 2023 may be scheduled to finish the work. The Alpine Road Trail will be closed during the construction seasons.