BOARD AGENDA MEMORANDUM
SUBJECT:
Title
Adopt a Resolution Adopting the Final Mitigated Negative Declaration and Mitigation Monitoring and Reporting Program and Approve the Calabazas Creek Bank Rehabilitation Project (Project), Project No. 62084001 (Task 5183) (Cupertino) (District 5).
End
RECOMMENDATION:
Recommendation
A. Consider the environmental effects of the Calabazas Creek Bank Rehabilitation Project (Project) as discussed in the Final Mitigated Negative Declaration;
B. Adopt the Resolution ADOPTING THE FINAL MITIGATED NEGATIVE DECLARATION AND MITIGATION MONITORING AND REPORTING PROGRAM FOR THE CALABAZAS CREEK BANK REHABILITATION PROJECT; and
C. Approve the Project.
Body
SUMMARY:
Background and Project Description
Santa Clara Valley Water District (Valley Water) is responsible for maintenance of most of Calabazas Creek, which extends approximately 13.3 miles from the confluence with the Guadalupe Slough on the San Francisco Bay upstream to the Saratoga foothills. The total drainage area of Calabazas Creek is 22.7 square miles, over 90% of which is urbanized. Consequently, maintenance of the creek channel is necessary to support the creek’s function as a flood protection facility, to prevent damage to adjacent properties from erosion, and to minimize impacts to the natural creek habitat (e.g. loss of habitat, reduced water quality).
The Project reach is located between Miller Avenue and Bollinger Avenue and is a deeply incised water course with little distance between top of the bank and the residential fence line, and the reach experiences bank erosion. Repairs in the Project reach were last completed in 2011, as part of Valley Water’s Calabazas Creek Flood Protection Project along 3.7 miles of Calabazas Creek from Miller Avenue to Wardell Road.
During the recent periodic inspections performed by Watersheds Operation & Maintenance staff, deficiencies were observed along the creek in the Project area including toe erosion, bank failure, and surfaces lacking vegetative cover. This Project area repair work was identified as one of the high priority Small Capital projects under the Watersheds Asset Rehabilitation Program (WARP). Many of creek’s deficiencies were exacerbated as the result of winter 2016/2017 storm events and require corrective action.
The Project would repair and stabilize channel banks that are eroding at 10 locations through the installation of rip-rap (six locations) or sheet pile retaining walls (four locations). Specific objectives of the Project are:
• Rehabilitate damaged creek bank sections to as-built or natural conditions, including to prevent potential damage to adjacent properties;
• Minimize future bank failure;
• Minimize impacts on water quality and riparian habitat associated with continued bank erosion;
• Reduce the need for on-going maintenance; and
• Continue to provide adequate flood protection.
Environmental Review
Pursuant to the California Environmental Quality Act (CEQA), Valley Water, as the lead agency for the Project, prepared a Final Mitigated Negative Declaration (MND), which can be accessed through the link provided as Attachment 1 for the Board’s consideration prior to approving the Project. The Draft MND was circulated for public review from September 18, 2020 to October 19, 2020. Valley Water received comments from the San Francisco Bay Regional Water Quality Control Board and the California Department of Fish and Wildlife.
Valley Water staff considered the public comments and included responses to the comments in Appendix H of the Final MND and made edits as appropriate in the Final MND to incorporate the responses to comments. The information added to the Final MND merely clarifies, amplifies, or makes insignificant modifications to the Draft MND, and thus no recirculation of the MND is required pursuant to Section 15073.5 of the CEQA Guidelines.
Summary of Environmental Impacts
As discussed in the Final MND, the Project would result in no or less than significant impacts in all resource areas except biological resources and noise.
Potentially significant impacts on biological resource (BIO) described in the MND include: habitat modification and direct harm from construction on special status species including San Francisco dusky-footed woodrat and western red bat; permanent loss of riparian habitat; and removal of trees protected under the City of Cupertino’s Protected Tree Ordinance. Mitigation Measures BIO-1 through BIO-3 would reduce potential impacts on special status species to a less than significant level by requiring construction workers receive an environmental awareness training and conducting pre-construction surveys for woodrats and bats to protect their nests and roosts, respectively, if identified. Mitigation Measure BIO-4 would reduce impacts on riparian habitat to a less than significant level by requiring restoration and/or enhancement of riparian habitats to compensate for permanent impacts. Mitigation Measures BIO-5 would reduce impacts on locally protected trees to a less than significant level through voluntary compliance with the City of Cupertino’s Protected Tree Ordinance, which would require replacement of protected trees and/or payment towards the City’s tree fund.
Potentially significant impacts from noise (NV) described in the MND are limited to temporary increase in noise levels from construction in excess of the thresholds established in the City of Cupertino’s Noise Ordinance. Mitigation Measures NV-1 through NV-4 would reduce this potential impact to a less than significant level by providing advanced notification of the construction schedule to adjacent residences, implementing work site noise control measures, designating a noise disturbance coordinator to address resident concerns, and installing temporary noise barriers if and where noise monitoring determines the Noise Ordinance thresholds would be exceeded at adjacent properties.
The mitigation measures are included in the Mitigation Monitoring and Reporting Program (MMRP) (Appendix F of the Final MND).
Next Steps
If the Board approves the recommendations, staff will continue to complete the Project design and obtain environmental permits necessary for Project implementation. The Board will be requested to adopt the plans and specifications and authorize advertisement for bids for construction in the future Board meeting. The typical Project Delivery Process Chart is provided in Attachment 3 for reference.
FINANCIAL IMPACT:
This Project is a part of WARP which is included in the Board-adopted Five-Year 2022-26 Capital Improvement Program (CIP) and the Board-adopted FY 2021-22 Budget. The estimated construction cost of the Project is approximately $12 million. WARP is funded by the Watersheds and Stream Stewardship Fund (Fund 12).
CEQA:
Valley Water is the lead agency under the CEQA for the Project. A Final MND has been prepared and is included for Board consideration and adoption before Project approval.
ATTACHMENTS:
Attachment 1: Final MND
Attachment 2: Resolution
Attachment 3: Project Delivery Process Chart
UNCLASSIFIED MANAGER:
Manager
Rechelle Blank, 408-630-2615