LOCATION HYDRAULIC STUDY SANTA CLARA VALLEY TRANSPORTATION AUTHORITY EL CAMINO REAL BUS RAPID TRANSIT PROJECT. February 2014 P R E P A R E D F O R :

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1 EA 04-3G980 LOCATION HYDRAULIC STUDY SANTA CLARA VALLEY TRANSPORTATION AUTHORITY EL CAMINO REAL BUS RAPID TRANSIT PROJECT P R E P A R E D F O R : Santa Clara Valley Transportation Authority 3331 North First Street San José, CA Contact: Christina Jaworski, Senior Environmental Planner P R E P A R E D B Y : WRECO 1243 Alpine Road, Suite 108 Walnut Creek, CA Contact: Analette Ochoa, P.E. (925) February 2014 February 2014

2 EA 04-3G980 ICF International El Camino Real Bus Rapid Transit Project. Location Hydraulic Study. February. San José, CA. Prepared for the Santa Clara Valley Transportation Authority, San José, CA. February 2014

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4 EA 04-3G980 February 2014

5 Table of Contents Executive Summary... v Acronyms...viii 1 General Description Project Description Introduction Project Location and Environmental Setting Overview Project Purpose and Need Alternatives Considered Construction Regulatory Setting Executive Order California s National Flood Insurance Program Design Standards FEMA Standards Affected Environment Watershed Description Traffic Traffic Interruptions for Base Flood (Q 100 ) FEMA Floodplains Floodplain at El Camino Real (PM-8.42) Floodplain at El Camino Real (PM-R10.76) Floodplain at El Camino Real (PM-R11.32) Floodplain of San Tomas Aquino Creek at El Camino Real (PM-12.81) Floodplain of Saratoga Creek at El Camino Real (PM-13.07) Floodplain of Calabazas Creek at El Camino Real (PM-13.66) Floodplain at El Camino Real (PM-15.60) Floodplain of Sunnyvale East Channel at El Camino Real (PM-15.97) Floodplain of Stevens Creek at El Camino Real (PM-18.96) Floodplain of Permanente Creek at El Camino Real (PM-20.43) Floodplain of Adobe Creek at El Camino Real (PM-22.34) Floodplain of Barron Creek at El Camino Real (PM-23.14) Floodplain of Matadero Creek at El Camino Real (PM-23.63) Environmental Consequences and Project Impacts Increase in Impervious Surfaces Summary of Potential Encroachments Potential Traffic Interruptions Due to the Proposed Action Potential Impacts on Natural and Beneficial Floodplain Values Support of Probable Incompatible Floodplain Development Longitudinal Encroachments Risk Associated with the Proposed Action Floodplain at El Camino Real (PM-8.42) Floodplain at El Camino Real (PM-R10.76) Floodplain at El Camino Real (PM-R11.32) Floodplain of San Tomas Aquino Creek at El Camino Real (PM-12.81) February 2014 i

6 4.3.5 Floodplain of Saratoga Creek at El Camino Real (PM-13.07) Floodplain of Calabazas Creek at El Camino Real (PM-13.66) Floodplain at El Camino Real (PM-15.6) Floodplain of Sunnyvale East Channel at El Camino Real (PM-15.97) Floodplain of Stevens Creek at El Camino Real (PM-18.96) Floodplain of Permanente Creek at El Camino Real (PM-20.43) Floodplain of Adobe Creek at El Camino Real (PM-22.34) Floodplain of Barron Creek at El Camino Real (PM-23.14) Floodplain of Matadero Creek at El Camino Real (PM-23.63) Avoidance, Minimization, and/or Mitigation Measures Minimize Floodplain Impacts Restore and Preserve Natural and Beneficial Floodplain Values Alternatives to Significant Encroachments Alternatives to Longitudinal Encroachments References Figures Figure 1. Project Location Map Figure 2. Project Corridor Map Figure 3. Project Alternatives Figure 4. Creek Crossings Figure 5. Overview of FEMA Floodplains Tables Table 1. El Camino Real BRT Project Alternatives... 3 Table 2. BRT Stations... 4 Table 3. Waterway Crossings in the Project Area... 9 Table 4. Average Daily Traffic at El Camino Real Bridge Crossings Table 5. Hydrologic and Hydraulic Information at Flooding Sources on El Camino Real Table 6. Changes in Impervious Area Table 7. Changes in Impervious Area by Percentage to Overall Drainage Area Table 8. Impacts to Nesting Birds due to Tree Removal in the Floodplain Areas Table 9. Summary of Floodplain Impacts Photos Photo 1. San Tomas Aquino Creek at Culvert Crossing Under El Camino Real Photo 2. Saratoga Creek at Bridge Crossing Under El Camino Real Photo 3. Calabazas Creek at Bridge Crossing Under El Camino Real (Looking Downstream) Photo 4. Sunnyvale East Channel at Culvert Crossing Under El Camino Real (Looking Downstream) February 2014 ii

7 Photo 5. Stevens Creek at Bridge Crossing Under El Camino Real Photo 6. Permanente Creek at Culvert Crossing Under El Camino Real Photo 7. Adobe Creek at Bridge Crossing Under El Camino Real (Looking Upstream) Photo 8. Barron Creek at Culvert Crossing Under El Camino Real (Looking Downstream) Photo 9. Matadero Creek at Bridge Crossing Under El Camino Real Appendices Appendix A Federal Emergency Management Agency Flood Insurance Rate Maps and Letters of Map Revisions Appendix B Summary Floodplain Encroachment Report Appendix C Location Hydraulic Study Forms February 2014 iii

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9 Executive Summary The Santa Clara Valley Transportation Authority (VTA) is proposing to provide bus rapid transit (BRT) improvements along 17.6 mi of El Camino Real and The Alameda. The Project corridor passes through the cities of San José, Santa Clara, Sunnyvale, Mountain View, Los Altos, and Palo Alto. The eastern terminus is located at the Arena in San José, and the western terminus is located at the Palo Alto Transit Center, in Palo Alto. The Project would include mixed-flow lanes (lanes for all vehicular travel) and could include BRT-dedicated lanes (lanes for exclusive use of BRT and emergency vehicles). Four alternatives are proposed including the No Build Alternative and three Build Alternatives including design options. Table A provides a brief description of each alternative. Each of the Build Alternatives includes mixed-flow lanes in the City of San José. The short and long dedicated lane alternatives include a combination of mixed-flow and dedicated BRT lanes elsewhere along the Project corridor. Table A. El Camino Real BRT Project Alternatives Alternative Name Abbreviated Name Description 1 No Build from San José to Palo Alto 2 All Mixed Flow from San José to Palo Alto Short Dedicated Lane 3a 3b Long Dedicated Lane 4a 4b 4c Lafayette Street to Halford Avenue in Santa Clara Lafayette Street to Halford Avenue plus Mixed Flow West of Halford Avenue Lafayette Street in Santa Clara to SR 85 in Mountain View Lafayette Street in Santa Clara to Showers Drive in Mountain View Lafayette Street in Santa Clara to Embarcadero Road in Palo Alto Alt 1 - No Build Alt 2 - All Mixed Flow Alt 3a - Short Dedicated (No Build West of Halford) Alt 3b - Short Dedicated (Mixed Flow West of Halford) Alt 4a - Long Dedicated (SR 85) Alt 4b - Long Dedicated (Showers Drive) Alt 4c - Long Dedicated (Embarcadero Road) VTA would not undertake any improvements to El Camino Real. No dedicated bus-only lanes with only mixed-flow lanes and full curbside bulbout stations. Mixed-flow lanes and full bulbout stations between San José and Lafayette Street in Santa Clara, dedicated lanes between Lafayette Street and Halford Avenue, and no improvements between Halford Avenue and Palo Alto. Dedicated lanes between Lafayette Street and Halford Avenue in Santa Clara with mixed-flow lanes and full curbside bulbout stations in all other areas. Dedicated lanes between Lafayette Street and SR 85 with mixed-flow lanes and full curbside bulbout stations in all other areas. Dedicated lanes between Lafayette Street and Showers Drive with mixed-flow lanes and full curbside bulbout stations in all other areas. Dedicated lanes between Lafayette Street and Embarcadero Road with mixed-flow lanes and full curbside bulbout stations in all other areas. Source: VTA, 2013 February 2014 v

10 Nine major waterways, including San Tomas Aquino Creek, Saratoga Creek, Calabazas Creek, Sunnyvale East Channel, Stevens Creek, Permanente Creek, Adobe Creek, Barron Creek, and Matadero Creek, cross El Camino Real (SR 82) within the Project limits. The crossings at Saratoga Creek, Calabazas Creek, Stevens Creek, and Adobe Creek are bridges, and the remaining four are cross culverts. A primary design goal for the Project is to avoid or minimize impacts to Federal Emergency Management Agency (FEMA) floodplains to the maximum extent practicable. The Flood Insurance Rate Maps (FIRMs) show that there are 13 floodplains within the Project limits. Three types of FEMA flood zones representing areas with a 1% annual chance of flooding were identified within the Project right-of-way: Zone A, Zone AO, and Zone AH. The Project will have minimal to no impacts to the floodplains within the Project limits. The Project will not support incompatible floodplain development. The Project does not constitute a longitudinal encroachment to the base floodplain. All creek crossings within the Project limits generally run perpendicularly to El Camino Real. Because the change in impervious area is insignificant compared with the overall watershed area draining to each creek, the Project will not pose a significant risk. Therefore, there will be no significant change in water surface elevation to the identified floodplains due to the changes in impervious areas. Table B includes a summary of the risks of the proposed Project for all FEMA floodplains within the Project limits. February 2014 vi

11 Table B. Summary of Floodplain Impacts Route Approximate Floodplain Post Mile Flood Source Alternatives That Result in Fill in the Floodplain % Area of Fill in the Floodplain Alternatives That Result in Change in Impervious Area Draining to the Floodplain % Change 1 Level of Impact El Camino Real El Camino Real El Camino Real El Camino Real El Camino Real El Camino Real El Camino Real El Camino Real El Camino Real El Camino Real El Camino Real El Camino Real El Camino Real 8.42 N/A None 0 None 0% None R10.76 N/A None 0 None 0% R11.32 N/A None 0 None 0% San Tomas Aquino Creek Saratoga Creek 3a, 3b, 4a, 4b, and 4c 3a, 3b, 4a, 4b, and 4c None None 0.06% 3a, 3b, 4a, 4b, and 4c % Minimal 0.04% 3a, 3b, 4a, 4b, and 4c % Minimal Calabazas Creek None 0 3a, 3b, 4a, 4b, and 4c % Minimal 15.6 N/A None 0 4a, 4b, and 4c - 2 Minimal Sunnyvale East Channel 4a, 4b, and 4c 1.50% 4a, 4b, and 4c % Minimal Stevens Creek 4b and 4c 0.04% None 0% Minimal Permanente Creek None 0 4b and 4c Adobe Creek None 0 4b and 4c % % to % Minimal Minimal Barron Creek None 0 4c 0.006% Minimal Matadero Creek None 0 4c % Minimal Notes: 1. Percentage (%) change in impervious area to overall watershed area draining to each creek. 2. % change is not calculated because there is no available data on the overall watershed area at this location. February 2014 vii

12 Acronyms ADT BFE BMPs Caltrans CFR DWR FEMA FHWA FIRM FIS ft LOMR mi NFIP RCB SCVWD sq mi SR SWPPP USGS VTA WSE average daily traffic base flood elevation best management practices California Department of Transportation Code of Federal Regulations Department of Water Resources Federal Emergency Management Agency Federal Highway Administration Flood Insurance Rate Map Flood Insurance Study feet Letter of Map Revision mile National Flood Insurance Program reinforced concrete box Santa Clara Valley Water District square mile State Route Storm Water Pollution Prevention Plan United States Geological Survey Santa Clara Valley Transportation Authority water surface elevation ort February 2014 viii

13 1 GENERAL DESCRIPTION 1.1 Project Description Introduction The Santa Clara Valley Transportation Authority (VTA) is proposing to provide bus rapid transit (BRT) improvements along 17.6 miles (mi) of El Camino Real. BRT is defined as a high-quality, high-speed form of bus transit that provides services and amenities similar to light rail but at a much lower cost. The El Camino Real BRT Project (Project) would support the development of a balanced multi-modal corridor consistent with local and regional planning. The Project would include mixed-flow lanes (lanes for all vehicular travel) and could include BRT-dedicated lanes (lanes for exclusive use of BRT and emergency vehicles). The Project would accommodate buses that would allow boarding level with the curb, pedestrian and bicycle enhancements, augmented landscaping, street lighting, and intersection improvements. The Project would also enhance the existing traffic signal system, giving buses priority at signals over general vehicular traffic Project Location and Environmental Setting Overview The Project is primarily located along El Camino Real 1, a state-owned route (State Route [SR] 82), in Santa Clara County (Project corridor) (Figure 1). In San José, the Project corridor is located on West Santa Clara Street and The Alameda; these facilities are under the jurisdiction of the City of San José. The Project corridor extends 17.6 mi from east to west and passes through the cities of San José, Santa Clara, Sunnyvale, Mountain View, Los Altos, and Palo Alto. The eastern terminus is located at the Arena in downtown San José, and the western terminus is located at the Palo Alto Transit Center, in downtown Palo Alto (refer to Figure 2). The Project corridor is a four-lane east-west facility in San José and a six-lane facility between Santa Clara and Palo Alto Project Purpose and Need The purpose of the El Camino Real BRT Project is to: Increase the reliability, frequency, and travel speed of transit along the El Camino Real corridor. Improve transit amenities and facilities to provide greater comfort and safety. Enhance the multi-modal character of El Camino Real, with street improvements for pedestrians and bicyclists. Contribute to the implementation of the transit goals and objectives of the Grand Boulevard Initiative (El Camino Real). Contribute to City General and Specific Plans that call for a greater role for transit to complement their growth strategies. Improve efficiency and cost-effectiveness of transit services in the corridor. 1 For the purposes of this environmental document, references to the Project corridor include West Santa Clara Street, The Alameda, and El Camino Real between the cities of San José and Palo Alto. February

14 The El Camino Real BRT Project is needed to address substantial population and employment growth over the next 20 years, which will place a heavy demand on existing transportation infrastructure. Within this timeframe, traffic volumes are anticipated to increase and a greater number of intersections along the Project corridor will experience a poor level of service. To encourage a modal shift from automobile travel to transit on the Project corridor, it will be necessary to provide better transit alternatives to ensure the continuation of effective and efficient transit service. This modal shift will be consistent with regional and local transportation planning described in the BRT Strategic Plan, and Grand Boulevard Initiative (GBI) Transportation Corridor Plan, and Plan Bay Area, as well as approved plans for the jurisdictions in the Project corridor Alternatives Considered Four Project alternatives are proposed including the No Build Alternative and three Build Alternatives including design options (refer to Figure 3). Table 1 shows the Alternative names and provides a brief description of each alternative. Each of the Build Alternatives includes mixed-flow lanes in the City of San José. The short and long dedicated lane alternatives include a combination of mixed-flow and dedicated lanes elsewhere along the Project corridor. Under all Build Alternatives, 14 existing bus stops along the Project corridor would be removed and replaced with new branded BRT stations (in addition three other optional BRT station locations are being considered, of which two may be chosen, for a total of up to 16 new BRT stations). Table 2 lists the locations of the proposed BRT stations. A brief description of the amenities included under the Build Alternatives follows. Mixed Flow Lanes. In mixed-flow lane segments between Santa Clara and Palo Alto, the Project would continue to provide six lanes (three lanes in each direction), and BRT stations would be constructed. These stations would include bulbouts and extend the sidewalk into the parking or curb lane to provide BRT buses with better station accessibility. Signal improvements would be installed at signal locations that do not currently have transit signal priority (TSP), but otherwise, there would be no other improvements between the station areas. Dedicated BRT Lanes. A dedicated lane configuration for a portion of the corridor between Santa Clara and Palo Alto would use two of the six lanes (one in each direction) exclusively for BRT transit and emergency vehicles only, leaving four general-purpose lanes for other traffic. The dedicated lanes would be center-running and would be 11 to 13 feet (ft) wide. At median stations, turn lanes would be maintained to the extent possible, with additional width for the stations gained by removing existing curbside parking or reducing the width of the existing median. At intersections where space allows, curb bulbouts would be constructed to shorten crossing distances. Signal improvements would be implemented at signals that do not currently have TSP. Parking. Curbside parking would be maintained to the extent possible, although some loss of street parking would occur under each of the Build Alternatives. Dedicated lane segments would include bicycle lanes in the place of parking. February

15 Figure 1. Project Location Map Source: ICF International, 2013

16 Figure 2. Project Corridor Map Source: ICF International, 2013

17 Figure 3. Project Alternatives Source: ICF International, 2013

18 BRT Vehicles. To clearly differentiate BRT service from local or other bus transit services, VTA would use distinctive vehicles and specialized branding to call out the BRT service as unique, innovative, and distinctive. Transit Signals. Additional TSP infrastructure would be provided throughout the Project corridor at signals in segments that do not now have TSP. Stations. New BRT stations would be equipped with enhanced amenities, similar to VTA s light rail stations. Table 1. El Camino Real BRT Project Alternatives Alternative Name Abbreviated Name Description 1 No Build from San José to Palo Alto 2 All Mixed Flow from San José to Palo Alto Short Dedicated Lane 3a 3b Long Dedicated Lane 4a 4b 4c Lafayette Street to Halford Avenue in Santa Clara Lafayette Street to Halford Avenue plus Mixed Flow West of Halford Avenue Lafayette Street in Santa Clara to SR 85 in Mountain View Lafayette Street in Santa Clara to Showers Drive in Mountain View Lafayette Street in Santa Clara to Embarcadero Road in Palo Alto Alt 1 - No Build Alt 2 - All Mixed Flow Alt 3a - Short Dedicated (No Build West of Halford) Alt 3b - Short Dedicated (Mixed Flow West of Halford) Alt 4a - Long Dedicated (SR 85) Alt 4b - Long Dedicated (Showers Drive) Alt 4c - Long Dedicated (Embarcadero Road) VTA would not undertake any improvements to El Camino Real. No dedicated bus-only lanes; only mixed-flow lanes and full bulbout stations. Mixed-flow lanes and full bulbout stations between San José and Lafayette Street in Santa Clara, dedicated lanes between Lafayette Street and Halford Avenue, and no improvements between Halford Avenue and Palo Alto. Dedicated lanes between Lafayette Street and Halford Avenue in Santa Clara with mixedflow lanes and full bulbout stations in all other areas. Dedicated lanes between Lafayette Street and SR 85 with mixed-flow lanes and full bulbout stations in all other areas. Dedicated lanes between Lafayette Street and Showers Drive with mixed-flow lanes and full bulbout stations in all other areas. Dedicated lanes between Lafayette Street and Embarcadero Road with mixed-flow lanes and full bulbout stations in all other areas. Source: VTA, 2013 February

19 Table 2. BRT Stations City Jurisdiction Proposed Station San José Santa Clara Sunnyvale Mountain View Los Altos Palo Alto Arena (this station is to be constructed by VTA s Santa Clara-Alum Rock [SCAR] BRT Project) Race/Julian Taylor/Naglee Santa Clara Transit Center Scott Kiely Flora Vista Wolfe Fair Oaks Hollenbeck Bernardo Castro Escuela (Optional Station) Showers Arastradero California Churchill or Embarcadero (Optional Station) Palo Alto Transit Center (existing) Alternative 1: No Build from San José to Palo Alto Alternative Source: VTA, 2013 Alternative 1, the No Build from San José to Palo Alto Alternative (No Build Alternative), would not include BRT service and assumes that the existing roadway and transit services in the Project corridor would continue. Local bus route 22 (Local 22) would continue to run in the El Camino Real corridor. Rapid 522 buses would be replaced in 2014 by BRT buses that would run at 10-minute headways. The 2014 BRT buses would provide near-level boarding, resulting in easier and faster boarding and off-boarding. Under Alternative 1, there would be no station improvements and no off-board fare collection. Alternative 2: All Mixed Flow from San José to Palo Alto Build Alternative 2, the All Mixed Flow from San José to Palo Alto (All Mixed Flow) Alternative, would provide mixed-flow lanes along the entire 17.6-mile Project corridor. This would include development of curbside bulbout BRT branded stations along the Project corridor. Alternative 3: Short Dedicated Lane Under Build Alternative 3, the Short Dedicated Lane Alternative, a certain portion of the Project corridor would have dedicated BRT Lanes. Under Build Alternative 3, there are two options (3a and 3b). Under each of the options, there would be mixed-flow lanes from the Arena in San José February

20 to Lafayette Street in Santa Clara and a 3.0-mile dedicated BRT lane from Lafayette Street in Santa Clara to Halford Street in Santa Clara. The two options differ in their configuration west of Halford Street to the Palo Alto Transit Center. Alternative 3a does not include any further BRT infrastructure west of Halford Avenue, and 3b includes a mixed-flow configuration with full bulbout stations (similar to Alternative 2) west of Halford Avenue. Alternative 4: Long Dedicated Lane Build Alternative 4, the Long Dedicated Lane Alternative, would provide a dedicated BRT lane segment along the Project corridor. There are three options considered under Alternative 4 (4a, 4b, and 4c) which differ based on the extent of the dedicated lane. Under each of the options, there would be mixed-flow lanes from the Arena in San José to Lafayette Street in Santa Clara and west of the dedicated lane terminus to the Palo Alto Transit Center. Alternative 4a would have a 7.1-mile dedicated lane segment from Lafayette Street in Santa Clara to SR 85 in Mountain View. Alternative 4b would have a 10.1-mile dedicated lane segment from Lafayette Street in Santa Clara to Showers Drive in Mountain View. Alternative 4c would have the longest dedicated lane segment (13.9 mi) from Lafayette Street in Santa Clara to Embarcadero Road in Palo Alto Construction Construction Scenario Construction of the Project would consist of BRT stations for passenger boarding, bus bulb-outs, paving, striping, and associated landscaping and utility improvements. BRT station platforms for mixed-flow lane scenarios would be constructed as an extension (i.e., bulb-out) of the existing sidewalk. BRT station platforms for dedicated lanes would be constructed in the street median. Should dedicated lanes be constructed as part of the Project, construction staging activities would occur within the two median lanes (in the center of the Project corridor). Should mixed-flow lanes be constructed as part of the Project, temporary closure of one existing through lane in each direction (two lanes) may be required in the vicinity of station platform construction. These lanes for curbside stations would be returned to through traffic after the majority of construction at any individual platform is completed. In order to minimize disruption to the traveling public that uses the Project corridor, it is anticipated that the Project would be constructed in stages, and existing sidewalks would remain intact to the greatest extent possible. It is anticipated that Project construction would take approximately two years to complete. To the extent feasible, detours/service interruptions would be disclosed to affected parties in advance and occur during non-peak periods. The following outlines the anticipated methods of construction staging for the purposes of identifying and evaluating potential construction impacts. Specific construction staging requirements will be defined during the final design process. February

21 Construction Activities The contractor s work plan would likely maximize productivity of the labor and equipment force employed, minimize mobilizations, and keep subcontractors workloads grouped together, while progressing through the Project corridor in a linear fashion. While the exact schedule would be prepared by the contractor, a logical approach would involve construction in these steps: Install construction area signage Relocate utilities Construct curb bulbouts and curbside bulbout stations Construct median stations Reconstruct BRT lanes Repair and overlay street Complete striping, signs, and landscaping To minimize construction impacts and shorten the total duration of construction, several noncontiguous areas would be constructed simultaneously. Within each area work would be sequenced such that individual traffic delays are minimized. Closures would require advance approval by the resident engineer and would be allowed mostly during periods of low traffic defined through traffic studies made during the design phase in support of the construction activity. The majority of construction would occur during daylight hours, but some nighttime work may be required to permit temporary closures for tasks that could interfere with daytime traffic or create safety hazards. Examples of these tasks include placing and removing temporary concrete barriers, certain utility relocation activities, canopy installation, or pavement conforms. During excavation, station construction, and pavement rehabilitation operations, the contractor would restrict parking and place long-term lane closures where work is active. The contractor would be required to safely protect the excavation each day during hours of non-activity. It is anticipated bicycles would share the road during this stage. The construction work through intersections would be performed under a flagging operation, half-width at a time, and temporary steel plates may be required to maintain traffic during non-working hours. A transportation management plan (TMP) would be developed in conjunction with the local municipalities prior to construction. The TMP would provide a plan for the advance notice to residents, businesses, motorists, transit users, and emergency service providers of construction activities and durations, temporary closures, detours, and access issues during each stage of construction. The TMP would identify services to facilitate the safe implementation of the February

22 construction project, such as increased California Highway Patrol presence during critical construction operations. 1.2 Regulatory Setting Executive Order Executive Order (Floodplain Management) directs all federal agencies to avoid, to the extent possible, long- and short-term adverse impacts associated with the occupancy and modification of floodplains, and to avoid direct and indirect support of floodplain development wherever there is a practicable alternative. Requirements for compliance are outlined in Title 23, Code of Federal Regulations, Part 650, Subpart A (23 CFR 650A) titled Location and Hydraulic Design of Encroachment on Floodplains. If the preferred alternative involves significant encroachment onto the floodplain, the final environmental document (final environmental impact statement or finding of no significant impact) must include: The reasons why the proposed action must be located in the floodplain. The alternatives considered and why they were not practicable, and A statement indicating whether the action conforms to applicable State or local floodplain protection standards California s National Flood Insurance Program The Federal Emergency Management Agency (FEMA) is the nationwide administrator of the National Flood Insurance Program (NFIP), which is a program that was established by the National Flood Insurance Act of 1968 to protect lives and property, and to reduce the financial burden of providing disaster assistance. Under the NFIP, FEMA has the lead responsibility for flood hazard assessment and mitigation, and it offers federally backed flood insurance to homeowners, renters, and business owners in communities that choose to participate in the program. FEMA has adopted the 100-year floodplain as the base flood standard for the NFIP. FEMA issues the Flood Insurance Rate Maps (FIRMs) for communities that participate in the NFIP. These FIRMs present delineations of flood hazard zones. In California, nearly all of the State s flood-prone communities participate in the NFIP, which is locally administered by the California Department of Water Resources (DWR) Division of Flood Management. Under California s NFIP, communities have a mutual agreement with the State and Federal government to regulate floodplain development according to certain criteria and standards, which is further detailed in the NFIP. Typically, each county (or community) has a Flood Insurance Study (FIS), which is used to locally develop FIRMs and Base Flood Elevations (BFE). The Project is located in Santa Clara County. FIS 06085CV001A, 002A, 003A, and 004A were published for Santa Clara County on May 18, The FIS volumes contain summary of discharge tables, floodway data tables, flood profiles, and other information about creeks crossing El Camino Real along the Project corridor. February

23 1.3 Design Standards FEMA Standards FEMA standards are employed for design, construction, and regulation to reduce flood loss and to protect resources. Two types of standards are often employed: design criteria and performance standards. A design criteria or specified standard dictates that a provision, practice, requirement, or limit be met; e.g. using the 1% flood and establishing floodway boundaries so as not to cause more than a 1-ft increase in flood stages. A performance standard dictates that a goal is to be achieved, leaving it to the individual application as to how to achieve the goal; e.g. providing protection to the regulatory flood, keeping post-development stormwater runoff the same as pre-development, or maintaining the present quantity and quality of water in a wetland. The 1% annual chance flood and floodplain have been adopted as a common design and regulatory standard in the United States. The NFIP adopted it in the early 1970s, and was adopted as a standard for use by all federal agencies with the issuance of Executive Order States or local agencies are free to impose a more stringent standard within their jurisdiction. February

24 2 AFFECTED ENVIRONMENT 2.1 Watershed Description Nine major waterways cross El Camino Real within the Project limits (see Figure 4). Five of these crossings are bridges, and the remaining four are cross culverts. These crossings were located from FEMA maps, as-built record drawings, and Caltrans Structure Maintenance Logs. The sizes and types of these crossings are discussed in the following sections and listed in Table 3. All creeks that pass through the Project limits are maintained by the Santa Clara Valley Water District (SCVWD). Table 3. Waterway Crossings in the Project Area Stream Name San Tomas Aquino Creek El Camino Real (SR 82) Post Mile Crossing Type Bridge Dimensions 1 Length Width Number of (ft) (ft) Spans Reinforced Concrete Box NA Saratoga Creek Bridge No Calabazas Creek Bridge No Sunnyvale East Channel Reinforced Concrete Box NA Stevens Creek Bridge No Permanente Creek Reinforced Concrete Box NA Adobe Creek Bridge No Barron Creek Reinforced Concrete Box NA Matadero Creek Bridge No Notes: 1. Bridge dimensions are from the California Log of Bridges on State Highways (Caltrans, 2013). February

25 San Tomas Aquino Creek (El Camino Real PM 12.81) San Tomas Aquino Creek crosses El Camino Real at the intersection of El Camino Real and San Tomas Expressway; see Photo 1. San Tomas Creek originates in the forested foothills of the Santa Cruz Mountains flowing in a northerly direction through the cities of Campbell and Santa Clara, into the Guadalupe Slough, and finally into the Lower South San Francisco Bay. The major tributaries to San Tomas Aquino Creek include Saratoga, Wildcat, Smith, and Vasona creeks. Of these, Saratoga Creek drains the largest area (17 square miles [sq mi]) and joins San Tomas Creek 1.5 mi upstream of U.S. Route 101. Most of the San Tomas Aquino watershed is developed as high-density residential neighborhoods, with additional areas developed for commercial and industrial uses. The majority of the San Tomas Aquino Creek channel has been modified and lined with concrete (from the Smith Creek confluence in the upper reaches downstream to U.S. Route 101) (Santa Clara Valley Urban Runoff Pollution Prevention Program [SCVURPPP]). San Tomas Aquino Creek at El Camino Real is estimated to have a drainage area of sq mi (FEMA, 2009). Saratoga Creek (El Camino Real PM 13.07) Saratoga Creek crosses El Camino Real approximately 1,400 ft west of the intersection of El Camino Real and San Tomas Expressway; see Photo 2. Saratoga Creek originates on the northeastern slopes of the Santa Cruz Mountains along Castle Rock Ridge at 3,100 ft in elevation. Saratoga Creek flows for approximately 4.5 mi in an easterly direction through forested terrain, largely contained within Sanborn County Park. It continues for about 1.5 mi through the low-density residential foothill region of the Town of Saratoga and then for another 8 mi along the alluvial plain of the Santa Clara Valley, and through the cities of San José and Santa Clara, which are characterized by high-density residential neighborhoods. Major tributaries include San Andres, Bonjetti, and Booker creeks (SCVURPPP). Saratoga Creek at El Camino Real is estimated to have a drainage area of sq mi (FEMA, 2009). Calabazas Creek (El Camino Real PM 13.66) Calabazas Creek crosses El Camino Real approximately 840 ft east of the intersection of El Camino Real and Pomeroy Avenue; see Photo 3. The Calabazas Creek watershed covers an area of approximately 20 sq mi. This 13.3-mile long creek originates from the northeast-facing slopes of the Santa Cruz Mountains and flows into the Lower South San Francisco Bay via the Guadalupe Slough. Major tributaries to Calabazas Creek include Prospect, Rodeo, and Regnart creeks. Additional sources of water to Calabazas Creek include the El Camino storm drain (and the Junipero Serra Channel). The creek traverses through a small portion of unincorporated County land, and flows through the cities of Saratoga, Cupertino, Sunnyvale, San José, and Santa Clara. The upper reaches of Calabazas Creek, where it passes through unincorporated County jurisdiction, and into Saratoga, are rural, and the creek is relatively untouched. The Calabazas Creek watershed is highly urbanized, predominantly with high-density residential neighborhoods (SCVURPPP). Calabazas Creek at El Camino Road is estimated to have a drainage area of sq mi (FEMA, 2009). February

26 NORTH NO SCALE Figure 4. Creek Crossings Source: USGS

27 Sunnyvale East Channel (El Camino Real PM 15.97) Sunnyvale East Channel crosses El Camino Real approximately 1,110 ft southeast of the intersection of El Camino Real and South Fair Oaks Avenue; see Photo 4. The Sunnyvale East Channel was constructed in 1967 to manage flooding that was becoming a problem due to subsidence of lands in the drainage area. The Sunnyvale East Channel watershed covers 7.1 sq mi extending from central Cupertino northeast through the City of Sunnyvale. The watershed draining to the channel is located entirely on the alluvial plain of the Santa Clara Valley. The channel is approximately 6 mi in length and extends from Interstate 280 in the south to Guadalupe Slough in the north. One quarter of it runs through underground culverts (SCVWD 2005b). It drains to the Lower South San Francisco Bay via the Junipero Serra Channel and the Guadalupe Slough. The Sunnyvale East Channel watershed is almost entirely urbanized with predominantly residential development (59%), as well as commercial and industrial land uses (23%) (SCVURPPP). Stevens Creek (El Camino Real PM 18.96) Stevens Creek crosses El Camino Real approximately 675 ft west of the intersection of El Camino Real and SR 85; see Photo 5. The Stevens Creek watershed covers an area of approximately 29 sq mi. The headwaters originate in the Santa Cruz Mountains within the City of Palo Alto and Santa Clara County. Much of the headwater area is protected open space managed by the County and the Midpeninsula Regional Open Space District. In the upper watershed, the mainstem flows southeast for about 5 mi along the San Andreas Fault, and another three mi northeast to the Stevens Creek Reservoir. From the reservoir, the Creek flows northward for a total of 12.5 mi through the foothills in the cities of Cupertino and Los Altos, and across the alluvial plain through the cities of Sunnyvale and Mountain View, finally draining into the Lower South San Francisco Bay. Below the reservoir, the watershed is largely developed with residential neighborhoods and commercial areas clustered along major surface streets such as El Camino Real. Tributaries above the reservoir include Montebello and Swiss creeks (SCVURPPP). Permanente Creek (El Camino Real PM 20.43) Permanente Creek crosses El Camino Real approximately 1,470 ft northwest of the intersection of El Camino Real and Miramonte Avenue; see Photo 6. Permanente Creek covers an area of approximately 17.5 sq mi on the northeast-facing slopes of the Santa Cruz Mountains. The headwaters originate near Black Mountain along the Montebello Ridge. Permanente Creek flows east through unincorporated County land for about 5 mi, then turns to the north at the base of the foothills and continues another 8 mi along the valley floor traversing through the cities of Los Altos and Mountain View, finally draining to the Lower South San Francisco Bay. The major tributaries are the West Branch Permanente Creek and Hale Creek. Unlike most watersheds in the Santa Clara Basin, the headwaters of the Permanente Creek are not protected as open space, but are developed for light industry and mining. Only the headwaters of the West Branch Permanente Creek are protected as open space by the Midpeninsula Regional Open Space District. The majority of the watershed downstream of this tributary confluence is developed as high-density residential neighborhoods, with commercial development clustered along major surface streets such as El Camino Real (SCVURPPP). Permanente February

28 Creek at El Camino Real is estimated to have a drainage area of sq mi (FEMA, 2009). Adobe Creek (El Camino Real PM 22.34) Adobe Creek crosses El Camino Real approximately 1,740 ft southeast of the intersection of El Camino Real and Arastradero Road; see Photo 7. The Adobe Creek watershed covers an area of approximately 10 sq mi in northwestern Santa Clara County, of which roughly 7.5 sq mi are mountainous and 2.5 sq mi are on the valley floor. Adobe Creek originates on the northeastern facing slopes of the Santa Cruz Mountains and flows northerly over steep forested terrain until it meets the Middle, West, and North Adobe Forks. Other major tributaries in the upper watershed are Moody and Purissima creeks. The drainage area above the confluence of the Adobe Forks is undeveloped open space. The remainder of the watershed primarily consists of residential development. Along the valley floor, Adobe Creek flows through Los Altos Hills, Los Altos, Palo Alto, and Mountain View. Adobe Creek is joined by Barron Creek west of U.S. Route 101 and continues to flow through estuarine area with tidal influence until it drains into the Palo Alto Flood Basin and then the Lower South San Francisco Bay (SCVURPPP). Adobe Creek at El Camino Real is estimated to have a drainage area of 8.50 sq mi (FEMA, 2009). Barron Creek (El Camino Real PM 23.14) Barron Creek crosses El Camino Real approximately 2,350 ft northwest of the intersection of El Camino Real and Arastradero Road; see Photo 8. The Barron Creek watershed covers an area of approximately 3 sq mi of urban development between the Matadero and Adobe creek watersheds. Barron Creek is approximately 5 mi long, originating in the low-density residential foothill region of the Town of Los Alto Hills and flowing in a northeasterly direction through residential, commercial, and industrial areas within the City of Palo Alto. The Creek joins neighboring Adobe Creek just upstream of U.S. Route 101 and drains via a tide gate to the Lower South San Francisco Bay through the Palo Alto Flood Basin. It has no major tributaries. Barron Creek has been greatly modified for flood control purposes; approximately 67 percent of the total length of creek bed has been hardened. Upstream of El Camino Real, the creek is piped for much of its length. Natural channel sections occur immediately adjacent to Arastradero Road and at the Barron Creek Debris Basin (SCVWD 2005a). Downstream of El Camino Real, Barron Creek is contained in a concrete trapezoidal channel. During wet storm events, high flows from Barron Creek may be diverted to Matadero Creek via the Barron Creek Bypass structure (SCVURPPP). Barron Creek at El Camino Real is estimated to have a drainage area of 2.60 sq mi (FEMA, 2009). Matadero Creek (El Camino Real PM 23.63) Matadero Creek crosses El Camino Real approximately 2,370 ft southeast of the intersection of El Camino Real and Oregon Expressway; see Photo 9. The Matadero Creek watershed covers an area of about 14 sq mi, of which approximately 11 sq mi are mountainous land, and 3 sq mi are gently sloping valley floor. Matadero Creek originates in the foothills of the Santa Cruz Mountains and flows in a northeasterly direction for approximately 8 mi until it discharges into the Palo Alto Flood Basin, and then drains February

29 into the Lower South San Francisco Bay. Major tributaries to Matadero Creek are Arastradero and Deer creeks and Stanford Channel. Through the foothills, Matadero Creek traverses through low-density residential development in the town of Los Altos Hills. As it nears the valley floor, it flows through the Stanford University Preserve and Campus, and then through residential, commercial, and industrial areas of Palo Alto. The portions of the watershed that are in the northern part of the City of Palo Alto are predominantly residential, commercial, and public/institutional (SCVURPPP). Matadero Creek at El Camino Real is estimated to have a drainage area of 7.60 sq mi (FEMA, 2009). 2.2 Traffic El Camino Real is a major state route used for emergency supply or evacuation, emergency vehicle access, school buses, and mail delivery. However, practical detour routes are available and can be made available during construction. Following is the summary of the traffic assessment: Emergency Supply or Evacuation Route: Emergency Vehicle Access: Practical Detour Route: School bus or mail route: Yes Yes Yes Yes Average daily traffic (ADT) information was obtained from the National Bridge Inventory Data as shown in Table 4. The future ADT as of 2040 is anticipated to be approximately 50,000 per the Project team. Table 4. Average Daily Traffic at El Camino Real Bridge Crossings Waterway Bridge Number Route PM ADT 1 Saratoga Creek El Camino Real ,000 Calabazas Creek El Camino Real ,000 Stevens Creek El Camino Real ,000 Adobe Creek El Camino Real ,250 Matadero Creek El Camino Real ,250 Source: National Bridge Inventory Data Notes: 1. ADT was as of Traffic Interruptions for Base Flood (Q 100 ) There are several areas within the Project corridor that are inundated during a 1% annual chance flood, and there may be associated traffic interruptions. During the time that the traffic on El Camino Real is interrupted, other local roads that are not flooded can be used as a detour route. February

30 3 FEMA FLOODPLAINS Floodplains were defined using the FEMA FIRMs. The FIRMs show that there are 13 floodplains within the Project limits. Three types of FEMA flood zones representing areas with a 1% annual chance of flooding were identified within the Project right-ofway: Zone AO, Zone A, and Zone AH. The following are FEMA s definitions of the three types of FEMA flood zones. Floodplains within hazard zone designation Zone AO represent areas with a 1% chance of shallow flooding, with specified flood depths of 1 to 3 ft. Floodplains identified as being within Zone A represent areas with a 1% annual chance of flooding, where base flood elevations have not been determined, and the floodplain has been analyzed by approximate methods based on historic information, existing hydrologic analyses, available data, and field observations. Floodplains identified as being within Zone AH represent areas with a 1% annual chance of shallow flooding, usually in the form of a pond, with specified flood depths of 1 to 3 ft. The FIS for Santa Clara County, CA and Incorporated Areas (2009) was used to obtain existing floodplain information within the Project area to supplement the data provided by the FIRMs. The FIS provides hydrologic information and explains the methods of analysis used to generate the floodplains shown on the FIRMs. The FIS also includes profiles of the floodplain elevations. Letters of Map Revision (LOMRs) were also used to obtain existing floodplain information. An overview of the floodplain maps is shown in Figure 5, and the FIRMs can be found in Appendix A. Table 5 summarizes the hydrologic, hydraulic, and floodplain information for the creek crossings within the Project area. February

31 Zone AH at PM R11.32 Zone AO at PM Zone AH at PM R10.76 Zone AO at PM 8.42 Figure 5. Overview of FEMA Floodplains Source: FEMA, 2009

32 Table 5. Hydrologic and Hydraulic Information at Flooding Sources on El Camino Real 1-Percent Water Surface Elevation (ft) Annual or Flood Depth (ft) Post At Creek Flood Source FIRM Panel(s) SFHA 1 Drainage Chance Peak Mile Crossing Area (mi 2 ) Discharge Upstream Downstream (cfs) Approximate Roadway Elevation (ft) Inundates El Camino Real N/A No 06085C0234H AO N/A N/A Depth 1' Yes R10.76 N/A No 06085C0231H AH N/A N/A Elevation Yes R11.32 N/A No 06085C0227H AH N/A N/A Elevation Yes San Tomas Aquino Creek Saratoga Creek Calabazas Creek Yes 06085C0227H, 06085C0226H AO/AH 3, Elevation 79 Depth 1' Yes Yes 06085C0226H A 4, Contained 3 Contained No 3 Yes 06085C0226H A 2, Contained 3 Contained 3 89 No N/A No 06085C0207H AO N/A N/A Depth 1.5' Yes Sunnyvale East Channel No 06085C0207H AO N/A N/A Depth 1.5' Yes Stevens Creek Yes 06085C0039H A N/A N/A N/A N/A Yes Permanente Creek Yes 06085C0039H AO 1, Depth Yes 06085C0036H Adobe Creek Yes and A 2, Contained 4 Contained No C0038H Barron Creek No 06085C0017H A Contained 4 Contained 4 42 No Matadero Creek Yes 06085C0017H A 2, Contained 4 Contained 4 39 No 4 Notes: 1. SFHA=Special Flood Hazard Area. 2. Based on information shown on FIRMs. 3. To be verified. FEMA flood profile not available at this location. 4. Confirmed by available FEMA flood profile at this location. Source: FEMA, 2009 and SCVWD February

33 3.1 Floodplain at El Camino Real (PM-8.42) According to FIRM 06085C0234H, a Zone AO floodplain is at the railroad underpass on El Camino Real, extending across El Camino Real and flooding the property on the south side of the roadway with a depth of 1 ft during a 1% annual chance shallow flooding (usually sheet flow on sloping terrain). 3.2 Floodplain at El Camino Real (PM-R10.76) According to FIRM 06085C0231H, a Zone AH floodplain is 0.1 mi southeast of the intersection of El Camino Real with Palm Drive, and extends onto El Camino Real in both directions, with a 1% annual chance water surface elevation (WSE) of 66 ft. This floodplain is subject to inundation by 1% annual chance shallow flooding (usually areas of ponding) and also covers much of the area south of El Camino Real. 3.3 Floodplain at El Camino Real (PM-R11.32) According to FIRM 06085C0227H, a Zone AH floodplain is south of the intersection of El Camino Real with De la Cruz Boulevard, and extends onto El Camino Real in both directions, with a 1% annual chance WSE of 65 ft. This floodplain is subject to inundation by 1% annual chance shallow flooding (usually areas of ponding) and also covers much of the area north of El Camino Real. 3.4 Floodplain of San Tomas Aquino Creek at El Camino Real (PM-12.81) The area at the San Tomas Aquino Creek crossing is a large floodplain, according to FIRMs 06085C0226H and 06085C0227H. This floodplain covers both sides of El Camino Real (including the traveled way in both directions), and extends to the north and south sides of El Camino Real. The FIRM designates the southern part of this large floodplain (south of El Camino Real) as Zone AH, with a 1% annual chance flood WSE of 79 ft; the FIRM designates the northern part of this large floodplain (south of El Camino Real) as Zone AO, with a 1% annual chance flood depth of 1 ft. 3.5 Floodplain of Saratoga Creek at El Camino Real (PM ) Saratoga Creek crosses El Camino Real 0.3 mi west of San Tomas Expressway. FIRM 06085C0226H identifies the area within the creek crossing as being within flood hazard Zone A, and indicates that the 1% annual chance flood discharge is entirely contained within the channel. The floodplain extends from north of Stevens Creek Boulevard/Doyle Road intersection to 1.5 mi upstream of U.S. Route 101 where it joins San Tomas Aquino Creek. Therefore, the Project roadway at this crossing is not inundated by the 1% annual chance flood. February

34 3.6 Floodplain of Calabazas Creek at El Camino Real (PM ) Calabazas Creek crosses El Camino Real approximately 840 ft east of the intersection of El Camino Real and Pomeroy Avenue. FIRM 06085C0226H identifies the area within the creek crossing as being within flood hazard Zone A, and indicates that the 1% annual chance flood discharge is entirely contained within the channel. The floodplain extends from north of Junipero Serra Freeway upstream to 0.5 mi north of U.S. Route 101. Therefore, the El Camino Real roadway at this crossing is not inundated by the 1% annual chance flood. 3.7 Floodplain at El Camino Real (PM-15.60) According to FIRM 06085C0207H, a Zone AO floodplain is on the eastbound side of El Camino Real 0.3 mi northwest of South Wolfe Road intersection with El Camino Real, and it floods the property on the south side of the roadway with a depth of 1.5 ft during a 1% annual chance shallow flooding. 3.8 Floodplain of Sunnyvale East Channel at El Camino Real (PM-15.97) Approximately 1,110 ft southeast of the intersection of El Camino Real and South Fair Oaks Avenue, FIRM number 06085C0207H shows the floodplain of Sunnyvale East Channel on the eastbound side of El Camino Real and flooding the property on the south side of the roadway. The FIRM lists this floodplain as Zone AO with a depth of 1.5 ft during a 1% annual chance flood. 3.9 Floodplain of Stevens Creek at El Camino Real (PM ) Stevens Creek crosses El Camino Real approximately 675 ft west of the intersection of El Camino Real and SR 85. According to FIRM 06085C0039H, there is a floodplain directly at the El Camino Real crossing, and this floodplain extends upstream from Homestead Road to downstream at the south of SR 85/SR 237 intersection. This area is designated as being within Zone A. This overtopping is due to insufficient capacity of the channel upstream of El Camino Real Floodplain of Permanente Creek at El Camino Real (PM-20.43) Permanente Creek crosses El Camino Real approximately 1,470 ft northwest of the intersection of El Camino Real and Miramonte Avenue. According to FIRM 06085C0039H, there is a floodplain directly at the El Camino Real crossing, and this floodplain extends approximately 0.35 mi southeast of the creek crossing and covers part of the SR 82 eastbound lanes. This area is designated as being within Zone AO with a depth of 1 ft, which represents the floodplain caused by the shallow sheet flow that overtops the banks of Permanente Creek during a 1% annual chance storm event. This February

35 overtopping is due to insufficient capacity of the channel upstream of El Camino Real. The creek area immediately downstream of the El Camino Real crossing is defined as being within Zone A Floodplain of Adobe Creek at El Camino Real (PM ) Adobe Creek crosses El Camino Real approximately 1,740 ft southeast of the intersection of El Camino Real and Arastradero Road. According to FIRMs 06085C0036H and 06085C0038H, there is a floodplain directly at the El Camino Real crossing. This area is designated as being within Zone A. The floodplain extends from upstream 0.2 mi west of Pine Lane in Los Altos to downstream at Grove Avenue in Palo Alto. The 1% annual chance flood discharge is entirely contained within the channel at the areas upstream and downstream of the crossing. The FEMA flood profile confirms that the 1% annual chance flood discharge is entirely contained within the channel at the crossing Floodplain of Barron Creek at El Camino Real (PM ) Barron Creek crosses El Camino Real approximately 2,350 ft northwest of the intersection of El Camino Real and Arastradero Road. FIRM 06085C0017H identifies the area within the channel on the downstream side of El Camino Real as being within flood hazard Zone A, and indicates that the 1% annual chance flood discharge is entirely contained within the channel. The FEMA flood profile confirms that the 1% annual chance flood discharge is entirely contained within the channel at the crossing. Therefore, the El Camino Real roadway at this crossing is not inundated by the 1% annual chance flood Floodplain of Matadero Creek at El Camino Real (PM ) Matadero Creek crosses El Camino Real approximately 2,370 ft southeast of the intersection of El Camino Real and Oregon Expressway. According to FIRM 06085C0017H, there is a floodplain directly at the El Camino Real crossing. This area is designated as being within Zone A. The floodplain extends upstream from 0.22 mi north of Foothill Expressway to downstream at Louis Road. The FEMA flood profile indicates that the 1% annual chance flood discharge is entirely contained within the channel at the crossing. February

36 4 ENVIRONMENTAL CONSEQUENCES AND PROJECT IMPACTS 4.1 Increase in Impervious Surfaces In addition to constructing BRT stations in both mixed-flow lanes and dedicated lanes, the Project will construct new landscaped and hardscaped medians as part of the dedicated lanes construction under Alternatives 3 and 4. Under Alternatives 3 and 4, the total areas of newly constructed landscaped median are greater than the total areas of newly constructed hardscaped median and newly constructed pavement. As a result, the landscaped median construction will reduce the impervious area within the Project limits, resulting in decreases in the peak runoff due to the addition of the amount of pervious surfaces available for infiltration of stormwater runoff. Table 6 and Table 7 summarize the amount of change in impervious area draining to each of the floodplains. The watershed areas for each creek at the creek crossings are also listed in the table for comparison. These watershed areas were taken from the FIS for Santa Clara County (see Table 5) when available; USGS StreamStats and Santa Clara County watersheds from SCVWD were used to determine the sizes of the remaining watershed areas. Added pervious areas and added impervious areas, as shown on the preliminary engineering plans, were delineated for the Project. The changes in impervious areas were determined by subtracting added impervious areas from added pervious areas, from the creek crossing locations to the nearest high points for each floodplain. Table 6. Changes in Impervious Area Approximate Drainage Floodplain Post Flood Source Area (ac) 1 Mile Total Change in Impervious Area Draining to the Floodplain (ac) by Alternative 2 3a 3b 4a 4b 4c 8.42 N/A R10.76 N/A R11.32 N/A San Tomas Aquino Creek 14, Saratoga Creek 10, Calabazas Creek 8, N/A Sunnyvale East Channel 2, Stevens Creek 14, Permanente Creek 9, Adobe Creek 5, Barron Creek 1, Matadero Creek 4, Source: 1. FEMA, USGS. February

37 Table 7. Changes in Impervious Area by Percentage to Overall Drainage Area Approximate Flood Source Drainage Area (ac) 1 % Changes in Impervious Area to Overall Drainage Area by Alternative Floodplain Post Mile 2 3a 3b 4a 4b 4c 8.42 N/A - 0% 0% 0% 0% 0% 0% R10.76 N/A - 0% 0% 0% 0% 0% 0% R11.32 N/A - 0% 0% 0% 0% 0% 0% San Tomas Aquino Creek 14,208 0% % % % % % Saratoga Creek 10,496 0% % % % % % Calabazas Creek 8, % % % % % % 15.6 N/A - 0% 0% 0% Sunnyvale East Channel 2,642 0% 0% 0% % % % Stevens Creek 14,912 0% 0% 0% 0% 0% 0% Permanente Creek 9,152 0% 0% 0% 0% % % Adobe Creek 5,440 0% 0% 0% 0% % % Barron Creek 1,664 0% 0% 0% 0% 0% 0.006% Matadero Creek 4,864 0% 0% 0% 0% 0% % Notes: 1. Source: FEMA, USGS. 2. % change is not calculated because there is no available data on the overall watershed area at this location. February

38 Because the change in impervious area is insignificant compared with the overall watershed area draining to each creek, the Project will not pose a significant risk. As shown in Table 6 and Table 7, the change in impervious area as a result of the Project is minimal in comparison to the overall watershed area for each creek (less than 0.01%). Therefore, there will be no significant change in WSE to the identified floodplains due to the change in impervious areas. 4.2 Summary of Potential Encroachments The Federal Highway Administration (FHWA) defines a significant encroachment as a highway encroachment, and any direct support of likely base floodplain development, that would involve one or more of the following construction or flood-related impacts: 1) significant potential for interruption or termination of a transportation facility that is needed for emergency vehicles or provides a community s only evacuation route; 2) a significant risk; or 3) a significant adverse impact on the natural and beneficial floodplain values (1994). The following sections discuss the potential impacts to the floodplain that result from the proposed action. The risk associated with implementation of the action is discussed in Section Potential Traffic Interruptions Due to the Proposed Action The Project does not have significant potential for interruption or termination of a transportation facility that is needed for emergency vehicles or provides a community s only evacuation route. Other local roads can be used for emergency vehicles or as evacuation routes. There may be traffic interruptions for the base flood (locations are summarized in Table 5, where the floodplain inundates El Camino Real), but traffic from El Camino Real may use the local roads that are not flooded for a detour route. The Project will not have a significant impact to the floodplains within the Project area, and therefore, will not have any adverse effect on traffic interruptions for the base flood Potential Impacts on Natural and Beneficial Floodplain Values Natural and beneficial floodplain values include, but are not limited to: fish, wildlife, plants, open space, natural beauty, scientific study, outdoor recreation, agriculture, aquaculture, forestry, natural moderation of floods, water quality maintenance, and ground water recharge. The Project would not result in fill of wetlands or other waters (ICF International, 2013). Nesting bird species, including Cooper s hawk and white-tailed kite, have the potential to nest in the trees within the Project median areas within the floodplains and could be disturbed by Project construction activities. Nesting birds are protected under the Migratory Bird Treaty Act and California Fish and Wildlife Code Sections 3503 and , all of which prohibit disturbances to active nests. Project activities could disturb active bird nests and result in nest abandonment and mortality of young if activities start or move into previously inactive areas during the bird nesting season from February 1 to August 31. Because Project activities are not expected to begin throughout the entire Project corridor simultaneously and could start or move into previously inactive portions February

39 of the corridor during the nesting season, surveys for nesting birds are expected to be necessary to avoid impacting active bird nests (ICF International, 2013). Under Alternatives 3a, 3b, 4a, 4b, and 4c, Project construction could result in potential impacts to nesting bird species that could nest in the trees in the median areas within the floodplains. Of the Build Alternatives, Alternatives 3a and 3b would result in fewer nesting bird impacts as no median construction within the floodplains are proposed west of Halford Avenue, and impacts would likely be limited to the floodplain at San Tomas Aquino Creek. Alternative 4c would have the most effects on nesting bird species dependent on final design. No impacts to nesting birds are anticipated as a result of the No Build Alternative and Alternative 2, which propose no median construction work in the floodplains; see Table 8. Refer to the Biological Resources Technical Memorandum (ICF International, 2013) for more detailed information including maps of trees marked for removal in the Project area. Table 8. Impacts to Nesting Birds due to Tree Removal in the Floodplain Areas Approximate Impacts to Nesting Birds by Alternative Floodplain Post Flood Source Mile 2 3a 3b 4a 4b 4c 8.42 N/A None None None None None None R10.76 N/A None None None None None None R11.32 N/A None None None None None None San Tomas Aquino Creek None Potential Potential Potential Potential Potential Saratoga Creek None None None None None None Calabazas Creek None None None None None None 15.6 N/A None None None None None None Sunnyvale East Channel None None None Potential Potential Potential Stevens Creek None None None None None None Permanente Creek None None None None Potential Potential Adobe Creek None None None None None Potential Barron Creek None None None None None None Matadero Creek None None None None None None Source: ICF International, 2013 February

40 4.2.3 Support of Probable Incompatible Floodplain Development As defined by the FHWA, the support of incompatible base floodplain development will encourage, allow, serve, or otherwise facilitate incompatible base floodplain development, such as commercial development or urban growth. The Project will construct BRT stations for passenger boarding, curb bulb-outs, and associated landscaping and utility improvements in an existing transit corridor, and will not create new access to developed or undeveloped land; therefore, the Project will not support incompatible floodplain development Longitudinal Encroachments As defined by the FHWA, a longitudinal encroachment is an action within the limits of the base floodplain that is longitudinal to the normal direction of the floodplain. A longitudinal encroachment is [a]n encroachment that is parallel to the direction of flow. Example: A highway that runs along the edge of a river is, usually considered a longitudinal encroachment. The requirement for consideration of avoidance alternatives must be included in a Location Hydraulic Study by including an evaluation and a discussion of the practicability of alternatives to any significant encroachment or any support of incompatible floodplain development. The Project does not constitute a longitudinal encroachment of the base floodplain. All creek crossings within the Project limits generally run perpendicularly to El Camino Real. 4.3 Risk Associated with the Proposed Action As defined by the FHWA, risk shall mean the consequences associated with the probability of flooding attributable to an encroachment. It shall include the potential for property loss and hazard to life during the service life of the bridge and roadway. The potential risk associated with the implementation of the proposed action includes but is not limited to: 1) change in land use, 2) fill inside the floodplain, or 3) change in the 100-year WSE. The measures to minimize the potential floodplain impacts associated with the action are summarized in Section 5. The proposed dedicated lanes are at-grade and the locations of new BRT stations are not within any floodplains; therefore, there will be no associated floodplain impacts as a result. There is potential fill inside the floodplain under Alternatives 3a, 3b, 4a, 4b, and 4c as a result of median construction. The overall change in land use due to median construction is minimal. The fill and the change in impervious area will have minimal impact on the 100-year WSE. The proposed curb at the median likely would have a height of 6 inches February

41 and therefore would not interrupt flood pattern. A summary of the potential risks associated with the proposed Build Alternatives is included in Table 9. February

42 Table 9. Summary of Floodplain Impacts Approximate Floodplain Post Mile Flood Source Alternatives That Result in Fill in the Floodplain Area of Fill in the Floodplain, ac Estimated Overall Floodplain Area, ac * % Area of Fill in the Floodplain Alternatives That Result in Change in Impervious Area Draining to the Floodplain 1 Level of % Change Impact 8.42 N/A None 0-0 None 0% None R10.76 N/A None 0-0 None 0% None R11.32 N/A None 0-0 None 0% None San Tomas 3a, 3b, 4a, 4b, Aquino Creek and 4c % 3a, 3b, 4a, 4b, and 4c % Minimal Saratoga 3a, 3b, 4a, 4b, Creek and 4c % 3a, 3b, 4a, 4b, and 4c % Minimal Calabazas Creek None a, 3b, 4a, 4b, and 4c % Minimal 15.6 N/A None a, 4b, and 4c - 2 Minimal Sunnyvale East Channel 4a, 4b, and 4c % 4a, 4b, and 4c % Minimal Stevens Creek 4b and 4c % None 0% Minimal Permanente Creek None b and 4c % Minimal Adobe Creek None b and 4c % to Minimal % Barron Creek None c 0.006% Minimal Matadero Creek None c % Minimal *Source: FEMA. Notes: 1. Percentage (%) change in impervious area to overall watershed area draining to each creek. 2. % change is not calculated because there is no available data on the overall watershed area at this location. February

43 4.3.1 Floodplain at El Camino Real (PM-8.42) There will be no impacts to the floodplain of El Camino Real at PM There will be no proposed construction in all Build Alternatives at this location. Therefore, the potential risk as a result of this Project is minimal at this location Floodplain at El Camino Real (PM-R10.76) There will be no impacts to the floodplain of El Camino Real at PM-R There will be no proposed construction in all Build Alternatives at this location. Therefore, the potential risk as a result of this Project is minimal at this location Floodplain at El Camino Real (PM-R11.32) There will be no impacts to the floodplain of El Camino Real at PM-R There will be no proposed construction in all Build Alternatives at this location. Therefore, the potential risk as a result of this Project is minimal at this location Floodplain of San Tomas Aquino Creek at El Camino Real (PM-12.81) Alternative 2 involves the removal of existing pork-chop islands, and there would be no fill in the floodplain. Therefore, the potential risk as a result of Alternative 2 is low at this location. Alternatives 3a, 3b, 4a, 4b, and 4c involve the construction of dedicated lanes, bike lanes, and median work in the floodplain. The construction of new landscaped median would constitute a fill in the floodplain. The area of the fill is insignificant compared to the overall floodplain area. The median construction will result in an increase in impervious area draining to the creek under Alternatives 3a, 3b, 4a, 4b, and 4c, but this increase will be insignificant compared to the overall watershed of the creek. The increase in impervious area will not significantly increase the 1% annual chance flood WSE; therefore, the potential risk as a result of Alternatives 3a, 3b, 4a, 4b, and 4c is low at this location Floodplain of Saratoga Creek at El Camino Real (PM-13.07) There will be no proposed construction in Alternative 2 at this location. Therefore, the potential risk as a result of Alternative 2 is minimal at this location. Alternatives 3a, 3b, 4a, 4b, and 4c involve the construction of dedicated lanes, bike lanes, and median work in the floodplain. The construction of new landscaped median would constitute a fill in the floodplain. The area of the fill is insignificant compared to the overall floodplain area. The median construction will result in a net decrease in impervious area draining to the creek under Alternatives 3a, 3b, 4a, 4b, and 4c, but this decrease will be insignificant February

44 compared to the overall watershed of the creek. The decrease in impervious area will not significantly decrease the 1% annual chance flood WSE; the potential risk as a result of Alternatives 3a, 3b, 4a, 4b, and 4c is low at this location Floodplain of Calabazas Creek at El Camino Real (PM-13.66) There will be no impacts to the floodplain of El Camino Real at PM There will be no proposed construction in all Build Alternatives within the floodplain at this location. Therefore, the potential risk as a result of all Build Alternatives is minimal at this location. The median construction within the drainage area to the floodplain will result in a net decrease in impervious area draining to the creek under Alternatives 3a, 3b, 4a, 4b, and 4c, but this decrease will be insignificant compared to the overall watershed of the creek. The decrease in impervious area will not significantly reduce the 1% annual chance flood WSE; the potential risk as a result of this Project is minimal at this location Floodplain at El Camino Real (PM-15.6) Under Alternatives 2, 3a, and 3b, there will be no impacts to the floodplain of El Camino Real at PM There will be no proposed construction in Alternatives 2, 3a, and 3b in the floodplain. Therefore, the potential risk as a result of Alternatives 2, 3a, and 3b is minimal at this location. Alternatives 4a, 4b, and 4c involve the construction of dedicated lanes and bike lanes at this location. The maintenance of existing hardscaped median would not constitute any fill in the floodplain. The median construction will result in a net decrease in impervious area draining to the creek under Alternatives 4a, 4b, and 4c; therefore, the potential risk as a result of Alternatives 4a, 4b, and 4c is low at this location Floodplain of Sunnyvale East Channel at El Camino Real (PM ) Under Alternatives 2, 3a, and 3b, there will be no impacts to the floodplain of El Camino Real at PM There will be no proposed construction in Alternatives 2, 3a, and 3b in the floodplain. Therefore, the potential risk as a result of Alternatives 2, 3a, and 3b is minimal at this location. Alternatives 4a, 4b, and 4c involve the construction of dedicated lanes, bike lanes, and median work in the floodplain. The construction of new landscaped median would constitute a fill in the floodplain. The area of the fill is insignificant compared to the overall floodplain area. The construction of new landscaped median would result in a net decrease in impervious area draining to the creek under Alternatives 4a, 4b, and 4c, although this decrease will be insignificant compared to the overall watershed of the creek. The decrease in February

45 impervious area will not significantly reduce the 1% annual chance flood WSE; the potential risk as a result of Alternatives 4a, 4b, and 4c is low at this location Floodplain of Stevens Creek at El Camino Real (PM-18.96) Under Alternatives 2, 3a, 3b, and 4a, there will be no impacts to the floodplain of El Camino Real at PM There will be no proposed construction in Alternatives 2, 3a, 3b, and 4a at this location. Therefore, the potential risk as a result of Alternatives 2, 3a, 3b, and 4a is minimal at this location. Alternatives 4b and 4c involve the construction of dedicated lanes, bike lanes, and median work at this location. The construction of new hardscaped median would constitute a fill in the floodplain. The area of the fill is insignificant compared to the overall floodplain area. There is no change in impervious area draining to the creek under all Build Alternatives, and therefore no impact to the 1% annual chance flood WSE; the potential risk as a result of this Project is low at this location Floodplain of Permanente Creek at El Camino Real (PM-20.43) Under Alternatives 2, 3a, 3b, and 4a, there will be no impacts to the floodplain of El Camino Real at PM There will be no proposed construction in Alternatives 2, 3a, 3b, and 4a at this location. Therefore, the potential risk as a result of Alternatives 2, 3a, 3b, and 4a is minimal at this location. Alternatives 4b and 4c involve the construction of dedicated lanes, bike lanes, and the maintenance of existing median and landscaping in the floodplain. The maintenance of existing median and landscaping would not constitute any fill in the floodplain. The median construction will result in a net decrease in impervious area draining to the creek under Alternatives 4b and 4c; therefore, the potential risk as a result of Alternatives 4b and 4c is low at this location Floodplain of Adobe Creek at El Camino Real (PM-22.34) Under Alternatives 2, 3a, 3b, 4a, and 4b, there will be no impacts to the floodplain of El Camino Real at PM There will be no proposed construction in Alternatives 2, 3a, 3b, 4a, and 4b at this location. Therefore, the potential risk as a result of Alternatives 2, 3a, 3b, 4a, and 4b is minimal at this location. Alternative 4c involves the construction of dedicated lanes, bike lanes, and median work in the floodplain. The construction of new hardscaped median would not constitute a fill in the floodplain because the FEMA flood profile indicates that the 1% annual chance flood discharge is entirely contained within the channel at the crossing. The median construction will result in a net decrease in impervious area draining to the creek under Alternatives 4b and 4c, although this decrease will be insignificant compared February

46 to the overall watershed of the creek. The decrease in impervious area will not significantly reduce the 1% annual chance flood WSE; the potential risk as a result of Alternative 4c is low at this location Floodplain of Barron Creek at El Camino Real (PM-23.14) There will be no impacts to the floodplain of El Camino Real at PM There will be no proposed construction within the FEMA floodplain of El Camino Real at PM in all Build Alternatives. Therefore, the potential risk as a result of the Build Alternatives is minimal at this location. The median construction under Alternative 4c within the drainage area to the floodplain will result in an increase in impervious area draining to the creek, but this increase will be insignificant compared to the overall watershed of the creek. The increase in impervious area will not significantly increase the 1% annual chance flood WSE; therefore, the potential risk as a result of Alternative 4c is minimal at this location Floodplain of Matadero Creek at El Camino Real (PM-23.63) Under Alternatives 2, 3a, 3b, 4a, and 4b, there will be no impacts to the floodplain of El Camino Real at PM There will be no proposed construction in Alternatives 2, 3, 4a, and 4b at this location. Therefore, the potential risk as a result of Alternatives 2, 3, 4a, and 4b is minimal at this location. Alternative 4c involves the construction of dedicated lanes, bike lanes, and median work at this location. The construction of new landscaped median would not constitute a fill in the floodplain because the FEMA flood profile confirms that the 1% annual chance flood discharge is entirely contained within the channel at the crossing. The median construction work under Alternative 4c will result in a net decrease in impervious area draining to the creek, although this decrease will be insignificant compared to the overall watershed of the creek. The decrease in impervious area will not significantly reduce the 1% annual chance flood WSE; the potential risk as a result of Alternative 4c is low at this location. February

47 5 AVOIDANCE, MINIMIZATION, AND/OR MITIGATION MEASURES 5.1 Minimize Floodplain Impacts The FIRMs show that there are 13 floodplains within the Project limits. In order to minimize impacts to the floodplains, the Project has avoided any fill in the floodplains whenever feasible and minimized additional impervious area that will result in additional flow to the floodplains. In addition, the Project will maintain existing median and landscaping whenever feasible to maintain the existing flow characteristics within the floodplains. The Project will also avoid any floodplain areas for all proposed BRT stations. As a result of these measures, the Project will have minimal to no impacts to the floodplains within the Project limits. 5.2 Restore and Preserve Natural and Beneficial Floodplain Values There are minimal anticipated impacts to areas with natural and beneficial floodplain values as a result of the Project. Refer to the Biological Resources Technical Memorandum (ICF International, 2013) for more details on efforts to restore and preserve natural and beneficial floodplain values. Prior to construction or site preparation activities, a qualified biologist will be retained to conduct nest surveys of appropriate nesting substrate. If active nests of migratory bird species protected under the Migratory Bird Treaty Act and the California Fish and Game Code are found sufficiently close to work areas to be disturbed by Project impact areas, an ornithologist, in consultation with the California Department of Fish and Wildlife, will determine the extent of a buffer zone to be established around the nest, which can range from 100 to 300 feet or more depending on the sensitivity of the nest or species. (ICF International, 2013). Environmentally sensitive areas (ESAs), if any, including wetlands, waters, and habitats that support sensitive species will be specified on contract documents to be protected. Contractor encroachment into ESAs will be prohibited. Currently no impacts are anticipated on jurisdictional areas such as wetlands or other waters. VTA will remove trees in the cities of San José, Santa Clara, Sunnyvale, Mountain View, Los Altos, and Palo Alto. VTA will also determine and implement tree mitigation in coordination with applicable municipalities (ICF International, 2013). In addition, the contractor will be required to prepare and submit a Storm Water Pollution Prevention Plan (SWPPP) to ensure water quality during the construction. The contractor will be required to install erosion control best management practices (BMPs), prevent asphalt concrete from entering live streams, and keep all staging areas away from the waters of the U.S. or wetlands. February

48 5.3 Alternatives to Significant Encroachments The Project will generally maintain the existing roadway alignment and profile. The impacts to the floodplains will be minimal due to the minor fill and minor changes in flows in localized areas. Therefore, the floodplain encroachments will not be significant. The Project will be primarily located along El Camino Real in Santa Clara County. In San José, the Project corridor is located on West Santa Clara Street and The Alameda. It will be impractical to relocate the Project. 5.4 Alternatives to Longitudinal Encroachments The Project does not constitute a longitudinal encroachment of the base floodplain. All creek crossings within the Project limits generally run perpendicularly to El Camino Real. At those locations where the roadway is inundated by the 1% annual chance flood, minimal fill and median structures that would decrease the flow area will be proposed at these areas. February

49 6 REFERENCES California Department of Transportation. (2011). California Log of Bridges on State Highways District 4. < (Last Accessed: July 5, 2013). Federal Emergency Management Agency. (2006). National Training and Education Emergency Management Institute. Floodplain Management An Integrated Approach. Chapter 13: Regulatory and Design Standards for Reducing Losses. < %20Regulatory%20and%20Design%20Standards%20for%20Reducing%20Lo.pd f> Federal Highway Administration. (2004). Code of Federal Regulations. Title 23 Highways. Sub-chapter G Engineering and Traffic Operations. Part 650 Bridges, Structures, and Hydraulics. Federal Highway Administration. (1994). Federal-Aid Policy Guide. Title 23, Code of Federal Regulations, Part 650, Subpart A (23 CFR 650A) Location and Hydraulic Design of Encroachment on Flood Plains. December 7, 1994, Transmittal 12. < Federal Emergency Management Agency. (May 18, 2009). Flood Insurance Study: and Incorporated Areas. Volumes 1-4 Federal Emergency Management Agency. (2009). Flood Insurance Rate Map, Santa Clara County, California and Incorporated Areas, Panel 10 of 830, (Map Number 06085C0010H). Federal Emergency Management Agency. (2009). Flood Insurance Rate Map, Santa Clara County, California and Incorporated Areas, Panel 16 of 830, (Map Number 06085C0016H). Federal Emergency Management Agency. (2009). Flood Insurance Rate Map, Santa Clara County, California and Incorporated Areas, Panel 17 of 830, (Map Number 06085C0017H). Federal Emergency Management Agency. (2009). Flood Insurance Rate Map, Santa Clara County, California and Incorporated Areas, Panel 36 of 830, (Map Number 06085C0036H). Federal Emergency Management Agency. (2009). Flood Insurance Rate Map, Santa Clara County, California and Incorporated Areas, Panel 38 of 830, (Map Number 06085C0038H). Federal Emergency Management Agency. (2009). Flood Insurance Rate Map, Santa Clara County, California and Incorporated Areas, Panel 39 of 830, (Map Number 06085C0039H). February

50 Federal Emergency Management Agency. (2009). Flood Insurance Rate Map, Santa Clara County, California and Incorporated Areas, Panel 45 of 830, (Map Number 06085C0045H). Federal Emergency Management Agency. (2009). Flood Insurance Rate Map, Santa Clara County, California and Incorporated Areas, Panel 206 of 830, (Map Number 06085C0206H). Federal Emergency Management Agency. (2009). Flood Insurance Rate Map, Santa Clara County, California and Incorporated Areas, Panel 207 of 830, (Map Number 06085C0207H). Federal Emergency Management Agency. (2009). Flood Insurance Rate Map, Santa Clara County, California and Incorporated Areas, Panel 226 of 830, (Map Number 06085C0226H). Federal Emergency Management Agency. (2009). Flood Insurance Rate Map, Santa Clara County, California and Incorporated Areas, Panel 227 of 830, (Map Number 06085C0227H). Federal Emergency Management Agency. (2009). Flood Insurance Rate Map, Santa Clara County, California and Incorporated Areas, Panel 231 of 830, (Map Number 06085C0231H). Federal Emergency Management Agency. (2009). Flood Insurance Rate Map, Santa Clara County, California and Incorporated Areas, Panel 233 of 830, (Map Number 06085C0233H). Federal Emergency Management Agency. (2009). Flood Insurance Rate Map, Santa Clara County, California and Incorporated Areas, Panel 234 of 830, (Map Number 06085C0234H). Federal Emergency Management Agency (2013). Letter of Map Revision, City of Santa Clara, Santa Clara County, CA, Community No , Case # P. Federal Emergency Management Agency (2009). Letter of Map Revision, City of Sunnyvale, Santa Clara County, CA, Community No , Case # P. ICF International. (2013). Biological Resources Technical Memorandum. National Bridge Inventory Data. Santa Clara County Bridges. < (Last Accessed: July 5, 2013). Santa Clara Valley Urban Runoff Pollution Prevention Program. Santa Clara Basin Watershed. < (Last Accessed: July 5, 2013). Santa Clara Valley Water District (SCVWD). SCVWD GIS Data. < (Last Accessed: July 5, 2013). February

51 United States Geological Survey. (2001). California: Seamless USGS Topographic Maps (CDROM, Version 2.6.8, Part Number: ). National Geographic Holdings, Inc. United States Geological Survey. StreamStats. < (Last Accessed: July 5, 2013). February

52 Photo 1. San Tomas Aquino Creek at Culvert Crossing Under El Camino Real (Looking Upstream) Photo 2. Saratoga Creek at Bridge Crossing Under El Camino Real (Looking Upstream)

53 Photo 3. Calabazas Creek at Bridge Crossing Under El Camino Real (Looking Upstream) Photo 4. Sunnyvale East Channel at Culvert Crossing Under El Camino Real (Looking Downstream)

54 Photo 5. Stevens Creek at Bridge Crossing Under El Camino Real (Looking Downstream) Culvert NORTH Photo 6. Permanente Creek at Culvert Crossing Under El Camino Real Source: Google Maps

55 Photo 7. Adobe Creek at Bridge Crossing Under El Camino Real (Looking Upstream) Flow Photo 8. Barron Creek at Culvert Crossing Under El Camino Real (Looking Upstream)

56 Photo 9. Matadero Creek at Bridge Crossing Under El Camino Real (Looking Upstream)

57 Appendix A Federal Emergency Management Agency Flood Insurance Rate Maps and Letters of Map Revisions February 2014 A-1

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