Portola Avenue Slide Repair
Summary
SCH Number
2026100838
Public Agency
City of Livermore
Document Title
Portola Avenue Slide Repair
Document Type
NOE - Notice of Exemption
Received
Posted
10/23/2026
Document Description
The project is located within the City right-of-way (ROW) along the north side of Portola Avenue, between I-580 and Isabel Avenue, in Livermore, CA. The project consists of work on a major arterial road in response to landslides caused by December 2022/January 2023 severe winter storms (CA23-1). The grassland pastures along the north side of Portola Avenue, between Campus Hill Drive and I-580, received a tremendous amount of rainfall with the resulting runoff flowing down the slopes. Due to poor soil conditions and excess rainfall, numerous slides occurred along the north side of Portola Avenue, spanning approximately 1,700 feet. Between the individual slope failures there was also evidence of slope movement due to soil cracks running along the top of slope, with several locations having cracks four to five inches wide.
The project will:
• Remove loose material and rebuild the slope with compacted engineered fill, keyed and benched into the existing slope;
• Install underdrains within limits of earthwork;
• Construct a concrete gutter at the top of slope and replace an earthen swale at the toe of slope; and
• Replace wildlife exclusion fencing affected by the project.
Contact Information
Name
Leon Taing
Agency Name
City of Livermore
Job Title
Senior Civil Engineer
Contact Types
Lead/Public Agency / Project Applicant / Parties Undertaking Project
Phone
Email
Location
Cities
Livermore
Counties
Alameda
Regions
Northern California, San Francisco Bay Area
Cross Streets
I-580, Isabel Avenue
State Highways
I-580
Other Location Info
North side of Portola Avenue, between I-580 and Isabel Avenue
Notice of Exemption
Exempt Status
Declared Emergency
Type, Section or Code
Sec. 21080(b)(3); 15269(a)
Reasons for Exemption
The project would make repairs to the segment of Portola Avenue damaged as a result of the Atmospheric River event of December 2022/January 2023. This event was proclaimed a state of emergency by Governor Newsom on January 4, 2023 (Executive Order N-1-23). The project would be limited to rebuilding the slope on the north side of Portola Avenue, constructing and repairing drainage infrastructure, and replacing wildlife exclusion fencing. Per Public Resources Code 21080(b)(3) and CEQA Guidelines Section 15269(a), the project is statutorily exempt from the provisions of CEQA.
County Clerk
Alameda
Attachments
Notice of Exemption
Disclaimer: The Governor’s Office of Land Use and Climate Innovation (LCI) accepts no responsibility for the content or accessibility of these documents. To obtain an attachment in a different format, please contact the lead agency at the contact information listed above. For more information, please visit LCI’s Accessibility Site.