Between December 27, 2022, and March 2023, unprecedented rainstorms caused severe damage to the two roadways within Mount Diablo State Park, forcing portions of both roads to be reduced to one lane traffic. For the Park’s primary access route, North Gate Road, high volume storm runoff flow overwhelmed an existing undersized roadway cross culvert, damaging the conduit and outfall, and causing an erosive landslide where approximately half of the roadway and shoulder were washed away. The condition of the remaining over-steepened terrain was compromised to an extent that the stability for on-going public use as a one-lane roadway was not recommended. North Gate Road is an essential route for park visitors, active cycling community, in-holding property owners and residents, maintenance for existing utility infrastructure, and first responders. The story of this team’s success, navigating funding, design, bid, and construction implementation within an extremely steep terrain environment, all within an approximate seven-month time frame, speaks to high capabilities and depth of experience of all that were involved. BKF prepared hydrology and hydraulic analysis of the existing 100+ acre drainage shed and has completed PS&E for the emergency repairs which completed construction in October 2023.

Project Highlights

• Disaster/Emergency Construction/Repair (FEMA)
• Hydrology and Hydraulic Analysis
• Plan Specifications & Estimates for the Emergency Repairs

Award

APWA Northern CA Chapter – Disaster or Emergency Construction/Repair – Less than $5 million – Feb 20, 2025