City of Richmond │ Via Verdi Emergency Response and Culvert Replacement Project

Richmond, CA

NCE arrived onsite with emergency personnel present to see a collapsed roadway, with residents unable to access their homes with their cars and two missing cars that fell into the very large sinkhole. Within less than 24 hours NCE designed a temporary access bridge to allow residents access back to their homes.
As an emergency response and permanent replacement to a very large collapsed section of culvert, this project challenged NCE’s interdisciplinary team to complete complicated analyses, design, and permitting processes under a very tight timeline of a year.
The replacement culvert required closing a major arterial street for 6 months to allow for excavation up to 60 feet in depth and threading the new culvert (over 20’ in width) below several sewer and gas lines and above the trunk water main from the San Pablo Reservoir.
Project Description

When a large sinkhole formed on Via Verdi in Richmond, CA, the City declared a local state of emergency due to its possible effects on San Pablo Creek, street infrastructure, utilities, critical habitat, and access to nearby communities.  

NCE was onsite within hours to assist the City with emergency response, which included designing temporary access bridges, bypass and emergency access roads, and site stabilization and erosion control measures; and helping the City coordinate with utility and regulatory agencies.  In less than a month, NCE was successful in completing design and CEQA documentation, obtaining all the necessary permits to excavate out the collapsed creek section and shore the creek channel, constructing a new temporary headwall, bank stabilization, erosion control and slope protection, and rerouting and relocating numerous major utility lines running through the site. 

Working with the City, utilities, regulatory agencies, and the public, NCE created innovative and complex design repair solutions within just 12 months. NCE completed civil and structural design, traffic engineering, restoration design, hydraulic modeling, preparation of environmental documents and secured all the necessary project permits including an Individual Permit (IP) with alternatives analysis. 

NCE’s civil and structural design of the replacement concrete box culvert, earthwork and grading, roadway and sidewalk reconstruction, creek slope protection, revegetation, protection of riparian habitat, utility line restoration to original locations, and protection and restoration of private property. Our team also delivered traffic engineering, engineering and environmental support during construction, restoration design, hydraulic modeling, environmental documents, and all the necessary project permits. The damaged roadway and collapsed culvert were successfully replaced and constructed in just over two years from the date of collapse.