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, the District has jurisdiction and manages 275 • San Francisquito Creek from S.F. Bay to Searsville miles to meet the Board’s Ends Policy E–3, “There is a Dam (Clean, Safe Creeks/Safe, Clean Water) healthy and safe environment for residents, businesses and visitors, as well as for future generations.” The West Valley Watershed district’s goals are further defined in E-3.1, “Provide Major Capital Improvements Completed natural flood protection for residents, businesses, • Calabazas Creek from Guadalupe Slough to Wardell and visitors” and E-3.2, “Reduce potential for flood Road damages.” The 275 miles of creeks are located in five • San Tomas Creek from Southern Pacific Railroad to watersheds: Lower Peninsula, West Valley, Guadalupe, Cabrillo Avenue Coyote, and Uvas/Llagas. The District administers an asset management program for its flood protection • Saratoga Creek from San Tomas Creek to infrastructure. The program includes a schedule for Lawrence Expressway maintenance and rehabilitation to ensure that each facility functions as intended throughout its useful life. Major Capital Improvements Identified in the CIP • Sunnyvale East and West Channels (Clean, Safe Fifty years of working for flood protection has Creeks) significantly reduced the intensity and frequency of flooding in Santa Clara County. By 2005 the District Guadalupe Watershed had provided flood protection to 93,253 of the 166,526 Major Capital Improvements Completed parcels in the flood plain and another approximately • Alamitos Creek 10,442 have been protected since then. • Guadalupe River–Lower from Alviso Marina to The voters in Santa Clara County have supported the Interstate 880 District’s flood protection efforts by approving benefit • Guadalupe River–Downtown from Interstate 880 to assessment funding in 1982, 1986, and 1990. Voters Interstate 280 approved a special parcel tax in 2000 and 2012 to fund the continuation of the District’s flood protection Major Capital Improvements Identified in the CIP capital improvements, specifically, moving upstream • Guadalupe River–Upper, Interstate 280 to Blossom from the completed downstream work or starting new Hill Road (Clean, Safe Creeks/Safe, Clean Water) work on creeks that have not had flood protection work. • Los Gatos Creek Restoration and Flood Protection Lower Peninsula Watershed (Safe, Clean Water) Major Capital Improvements Completed • Guadalupe River, Tasman Drive to I-880 • Adobe Creek from El Camino to West Edith Ave. Coyote Watershed • Barron Creek Major Capital Improvements Completed • Matadero Creek from Palo Alto Flood Basin to • Coyote Creek from S.F. Bay to Montague Barron Creek Expressway • Stevens Creek from Highway 101 to • Lower Penitencia Creek from Coyote Creek to Homestead Road Tasman Drive • Lower Silver Creek from Coyote Creek to Major Capital Improvements Identified in the CIP Cunningham Ave. (Reaches 1-6) • Palo Alto Flood Basin Structure Improvements • Wrigley Ford Creek 2020–2024 Five-Year Capital Improvement Program :: III-1 Flood Protection Capital Improvements Major Capital Improvements Identified in the CIP process and financial analysis are summarized in Appendix B. • Berryessa Creek from Calaveras Boulevard to Old Piedmont Road (Clean, Safe Creeks) Funding required for portions of several CIP projects is • Berryessa Creek from Lower Penitencia Creek to contingent on grants and partnership agreements that Calaveras Boulevard are under development and not currently secured. As the • Coyote Creek Montague Expressway to Tully Road District works through the process to secure funding the (Clean, Safe Creeks/Safe, Clean Water) project schedules may be adjusted. Projects with unsecured funding include: • Upper Penitencia Creek from Coyote Creek to Dorel Drive (Safe, Clean Water) • San Francisquito Creek, u/s Hwy 101 • Upper Llagas, Phase 2 (Reaches 5, 6, 7B, 8, and 14) Uvas/Llagas Watershed • Coyote Creek, Montague Expy. to Tully Road Major Capital Improvements Completed (actual cost will not be known until the planning • Llagas Creek–Lower from Pajaro River to Buena study is completed in January 2020) Vista Road • Uvas Creek It is understood that new capital projects have an impact on future operations and maintenance, and this is included in Major Capital Improvements Identified in the CIP the financial analysis. Periodically throughout the project, • Llagas Creek Capacity Restoration from Buena projections of this impact are updated to reflect changes in Vista Road to Pajaro River the project elements. • Llagas Creek–Upper, Buena Vista Road to Llagas Road (Clean, Safe Creeks/Safe, Clean Water) Flooding on Coyote Creek caused by severe storm in February 2017 led the District to reevaluate the Multiple Watersheds schedule, level of flood protection, and funding sources Major Capital Improvements Identified in the CIP for the Coyote Creek Project. A public hearing was held on June 13, 2017 to extend the Coyote Creek • San Francisco Bay Shoreline (Safe, Clean Water) project to Tully Road and evaluate a project that would • Watershed Asset Rehabilitation Program provide protection from a 20- to 25-year flood event. Staff worked with the Board CIP Committee to identify PRIORITY PROCESS AND possible funding for construction of this project. FINANCIAL ANALYSIS The Fiscal Year 2019-23 priority criteria for evaluating District staff collects high water marks from significant new flood protection projects were carried over to the storm events, conducts topographic surveys and Fiscal Year 2020-24 priority setting process to allow collected information on vegetation growth following time for further discussions on whether changes to the 2017 storm events. The analyses, completed in 2018 the criteria were needed. The priority criteria used are for Lower Guadalupe River, indicate that a section of the included in Appendix A. Lower Guadalupe River, from upstream of Tasman Drive to Airport Parkway, no longer has conveyance capacity A financial analysis of the Watershed and Steam for the 100-year event for which it was designed. The Stewardship Fund and Safe, Clean Water Fund, District is actively exploring options to restore the river the funding sources for flood protection capital to 100-year flow capacity, but there are many challenges improvements, was conducted to determine if there are ahead. Preliminary assessments indicate that vegetation limitations to funding all of the projects proposed for removal as permitted under the existing SMP alone will the Fiscal Year 2020-24 CIP. Results of the prioritization not be enough to restore the design conveyance. The Guadalupe River, Tasman Drive to I-880 Project was, III-2 :: 2020–2024 Five-Year Capital Improvement Program Flood Protection Capital Improvements included in the FY 2020-24 CIP to; investigate options for Partially Funded and Unfunded CIP Projects immediate interim measures and to conduct an alternatives • Coyote Creek, Montague Expy. to Tully Road (actual analysis and environmental evaluation of additional measures, cost will not be known until the planning study is such as construction of a floodwall or levee raising to re- completed in January 2020) establish flow conveyance capacity and freeboard for a 100- year event. • San Francisquito Creek 100 year flood protection upstream of Highway 101 The voter approved Safe, Clean Water program is providing • Upper Berryessa Creek, I-680 to Old Piedmont Road funding for some of the highest priority flood protection (unfunded; $20 million) projects including: • Upper Llagas, Reach 14 • Permanente Creek, San Francisco Bay to • Upper Penitencia Creek, Coyote Creek to Dorel Foothill Expy. Drive (USACE funding is unlikely) • 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 (Partial funding) • Upper Llagas Creek, Buena Vista Rd. to Llagas Rd. • San Francisco Bay Shoreline - Design and Partial Construction of EIA 11 and Planning for other EIAs • Los Gatos Creek Restoration and Flood Protection An implementation schedule for the Safe, Clean Water projects is available in Appendix E. Delays in the federal funding for many of the USACE projects have extended the schedules beyond the dates committed by the District. Therefore, the District is evaluating the option of proceeding with the local funding option on several of these projects. The following high priority flood protection projects, unfunded or partially funded, are of major concern to meet the Board’s Ends Policy E–3, “There is a healthy and safe environment for residents, businesses and visitors, as well as for future generations.” 2020–2024 Five-Year Capital Improvement Program :: III-3 Flood Protection Capital Improvements The following table is a project funding schedule for flood protection capital improvements resulting from this year’s priority process and financial analysis. Detailed information for each project can be found in this document on the followingThe followin pagesg table isin a theproj eorderct fund ipresentedng schedule infor thisfloo dtable. protec tiTheon c achartpital i malsoprove identifiesments resu ltipartiallyng from thfundedis year's projectspriority pr oandcess aestimatednd financia l unspentanalysis.