Flood Protection Capital Improvements
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Flood Protection Capital Improvements FLOOD PROTECTION OVERVIEW • Permanente Creek from S.F. Bay to Foothill Of the approximately 800 miles of creeks in Santa Clara Expressway (Safe, Clean Water) County, Valley Water has jurisdiction over and manages approximately 275 miles to meet the Board’s Ends Major Capital Improvements Identified in the CIP Policy E–3, “There is a healthy and safe environment • Palo Alto Flood Basin Structure Improvements for residents, businesses and visitors, as well as for • Permanente Creek from S.F. Bay to Foothill future generations.” Valley Water’s goals are further Expressway (Safe, Clean Water) defined in E-3.1, “Provide natural flood protection for • San Francisquito Creek from Highway 101 to residents, businesses, and visitors” and E-3.2, “Reduce Searsville Dam (Safe, Clean Water) potential for flood damages.” The 275 miles of creeks are located in five watersheds: Lower Peninsula, West West Valley Watershed Valley, Guadalupe, Coyote, and Uvas/Llagas. Valley Major Capital Improvements Completed Water administers an asset management program for its flood protection infrastructure. The program includes a • Calabazas Creek from Guadalupe Slough to Wardell schedule for maintenance and rehabilitation to ensure Road that each facility functions as intended throughout its • San Tomas Creek from Southern Pacific Railroad to useful life. Cabrillo Avenue • Saratoga Creek from San Tomas Creek to Fifty years of flood protection management has Lawrence Expressway significantly reduced the intensity and frequency of flooding in Santa Clara County. By 2005, Valley Water Major Capital Improvements Identified in the CIP had provided flood protection to 93,253 of the 166,526 parcels in the floodplain and another approximately • Sunnyvale East and West Channels (Clean, Safe 10,445 have been protected since then. Creeks) The voters in Santa Clara County have supported Valley Guadalupe Watershed Water’s flood protection efforts by approving benefit Major Capital Improvements Completed assessment funding in 1982, 1986, and 1990. Voters • Alamitos Creek also approved a special parcel tax in 2000 and 2012 to • Guadalupe River–Lower from Alviso Marina to fund the continuation of Valley Water’s flood protection Interstate 880 capital improvements; specifically, moving upstream • Guadalupe River–Downtown from Interstate 880 to from the completed downstream work or starting new Interstate 280 work on creeks that have not had flood protection work. Major Capital Improvements Identified in the CIP Lower Peninsula Watershed • Guadalupe River–Upper, Interstate 280 to Blossom Major Capital Improvements Completed Hill Road (Clean, Safe Creeks/Safe, Clean Water) • San Francisquito Creek from the S.F. Bay to Highway 101 (Clean, Safe Creeks/Safe, Clean • Guadalupe River, Tasman Drive to I-880 Water) Coyote Watershed • Adobe Creek from El Camino to West Edith Ave. Major Capital Improvements Completed • Barron Creek • Coyote Creek from S.F. Bay to Montague • Matadero Creek from Palo Alto Flood Basin to Expressway Barron Creek 2021–2025 Five-Year Capital Improvement Program :: III-1 Flood Protection Capital Improvements • Lower Penitencia Creek from Coyote Creek to The Board then authorizes release of the Draft CIP to Tasman Drive the public and local municipalities for review, conducts • Lower Silver Creek from Coyote Creek to a public hearing, and approves the resolution to adopt Cunningham Ave. (Reaches 1-6) the Final CIP in May. • Wrigley Ford Creek A financial analysis of the Watershed and Stream Stewardship Fund and Safe, Clean Water Fund, the Major Capital Improvements Identified in the CIP funding sources for flood protection capital • Berryessa Creek from Calaveras Boulevard to improvements, was conducted to determine if there are Interstate 680 (Clean, Safe Creeks) limitations to funding all of the projects proposed for • Berryessa Creek from Lower Penitencia Creek to the FY 2021-25 CIP. Calaveras Boulevard Funding required for portions of several CIP projects is • Coyote Creek Montague Expressway to Tully Road contingent on grants and partnership agreements that are (Clean, Safe Creeks/Safe, Clean Water) under development and not currently secured. As Valley • Upper Penitencia Creek from Coyote Creek to Water works through the process to secure funding the Dorel Drive (Safe, Clean Water) project schedules may be adjusted. Projects with unsecured funding include: Uvas/Llagas Watershed Major Capital Improvements Completed • San Francisquito Creek, upstream of Hwy 101 • Llagas Creek–Lower from Pajaro River to Buena • Upper Llagas, Phase 2 (Reaches 5, 6, 7B, 8, and 14) Vista Avenue It is understood that new capital projects have an impact on • Uvas Creek future operations and maintenance, and this is included in Major Capital Improvements Identified in the CIP the financial analysis. Periodically throughout the project, projections of this impact are updated to reflect changes in • Llagas Creek-Lower, Capacity Restoration from the project elements. Buena Vista Avenue to Pajaro River • Llagas Creek–Upper, Buena Vista Avenue to Llagas Valley Water staff collects high water marks from Road (Clean, Safe Creeks/Safe, Clean Water) significant storm events. Following extreme weather in 2017, Valley Water conducted topographic surveys Multiple Watersheds and collected information on vegetation growth. The Major Capital Improvements Identified in the CIP analyses, completed in 2018 for Guadalupe River, • San Francisco Bay Shoreline (Safe, Clean Water) indicated that a section of the Guadalupe River, from upstream of Tasman Drive to Airport Parkway, no longer • Watershed Asset Rehabilitation Program has conveyance capacity for the 100-year event for which it was designed. Valley Water is actively exploring CIP PLANNING PROCESS AND options to restore the river to 100-year flow capacity FINANCIAL ANALYSIS and has performed significant vegetation removal during The annual CIP Planning Process starts with collecting the FY 2019-20 stream maintenance season, but there information on proposed new capital projects in July, are many challenges ahead. Preliminary assessments followed by the validation of proposed new projects, indicate that vegetation removal as permitted under the preliminary scoping, review and financial analyses to existing SMP alone will not be enough to restore the produce a Draft CIP in February. design conveyance. The Guadalupe River, Tasman Drive III-2 :: 2021–2025 Five-Year Capital Improvement Program Flood Protection Capital Improvements to I-880 Project was included in the FY 2020-24 CIP to The following high priority flood protection projects, investigate options for immediate interim measures and unfunded or partially funded, are of major concern to to conduct an alternatives analysis and environmental meet the Board’s Ends Policy E–3, “There is a healthy and evaluation of additional measures, such as construction safe environment for residents, businesses and visitors, as of a floodwall or levee raising to re-establish flow well as for future generations.” conveyance capacity and freeboard for a 100-year event. Partially Funded and Unfunded CIP Projects The project’s funding has been increased by $95 million • San Francisquito Creek 100-year flood protection in the FY 2021-25 CIP to reflect all future planning, design upstream of Highway 101 and construction costs to restore design flow conveyance • Llagas Creek-Upper, Buena Vista Avenue to Llagas capacity. Road The Palo Alto Flood Basin Tide Gate Structure • Upper Penitencia Creek, Coyote Creek to Dorel Improvement Project increased in cost by $20 million due Drive (USACE funding is unlikely) to increased construction phase cost estimates The voter approved Safe, Clean Water Program is providing funding for some of the highest priority flood protection projects, including: • Permanente Creek, San Francisco Bay to Foothill Expy. • San Francisquito Creek, SF Bay to Middlefield Road • Sunnyvale East & West Channels • Upper Guadalupe River, I-280 to Blossom Hill Road • Upper Penitencia Creek, Coyote to Dorel Drive • Berryessa Creek, Calaveras Blvd. to I-680 • Coyote Creek, Montague Expy. to I-280 • Llagas Creek-Upper, Buena Vista Avenue to Llagas Road • San Francisco Bay Shoreline - Design and Partial Construction of EIA 11 and Planning for other EIAs An implementation schedule for Safe, Clean Water projects is available in Appendix C. Delays in federal funding for many of the U.S. Army Corps of Engineers (USACE) projects have extended project schedules beyond the dates committed by Valley Water. Therefore, Valley Water is evaluating the option of proceeding with the local funding option on several of these projects. 2021–2025 Five-Year Capital Improvement Program :: III-3 Flood Protection Capital Improvements Flooding on Coyote Creek caused by severe storm in February 2017 led Valley Water to reevaluate the schedule, level of flood protection, and funding sources for the Coyote Creek Project. A public hearing was held on June 13, 2017 to extend the Coyote Creek project to Tully Road and evaluate a project that would provide protection from a 20- to 25-year flood event. A preliminary cost range of $40-85 million was identified through a planning study and presented to the Board in December 2019. Based upon the project’s remaining secured funding of approximately $28 million, the project was deemed to have a shortfall between $12-57 million. Staff worked with the Board CIP Committee to identify possible funding for construction of this project. In re- sponse