Multi-Benefit Planning in the San Joaquin River Basin-wide Feasibility Study

Transcription

1 Multi-Benefit Planning in the San Joaquin River Basin-wide Feasibility Study September 8 th, 2016 Presented by: Eric Tsai, P.E. California Department of Water Resources Eric.Tsai@water.ca.gov Jeremy Thomas, M.L.A. CH2M Jeremy.Thomas@ch2m.com 1

2 Presentation Overview Background and Context Multi-Benefit Planning Lessons Learned and Next Steps 2

3 Background and Context 3

4 2017 Update to the CVFPP CVFPP is a dynamic, programmatic plan, updated in five year cycles CVFPP first adopted in 2012, first Update in Update has same goals and planning horizon as 2012 CVFPP (30 years) Refines and updates the State Systemwide Investment Approach (SSIA) Adds specificity about recommended near and longerterm investment and financing approach Provides broad guidance about more resilient risk management Coordinated and aligned with other major flood management efforts 4

5 San Joaquin Basin-wide Feasibility Study San Joaquin River BWFS Purpose: Refines the scale and location of major system elements Informs potential State interest in regional-scale elements Integrates environmental conservation with flood improvements 2012 CVFPP State Systemwide Investment Approach 5

6 CVFPP Draft Conservation Strategy Serves as roadmap for ecosystem improvement priorities Provides guidance and measureable objectives for: Improving and enhancing dynamic hydrologic and geomorphic processes Improving habitat Reducing stressors Conserving target species 6

7 Multi-Benefit Planning 7

8 BWFS Objectives CVFPP Goals BWFS Objectives Reduce Flood Damages from large flood events Improve Flood Risk Management Reduce life loss from large flood events Achieve and maintain 200-year level of protection for urban areas Achieve and maintain 100-year level of protection for small communities Reduce stages In urban areas, small communities, and rural-agricultural areas Ecosystem Processes Improve natural dynamic hydrologic and geomorphic processes in the SPFC Habitats - Increase and improve quantity, diversity, quality, and connectivity of riverine aquatic and floodplain habitats Promote Ecosystem Functions Species - Contribute to the recovery and sustainability of native species populations and overall biotic community diversity Stressors - Reduce stressors related to the development and operation of the SPFC that negatively affect at-risk species Cumulative Benefits to Ecosystems - Increase and improve quantity, diversity, quality, and connectivity of riverine aquatic and floodplain habitats Promote Multi-Benefit Projects Improve water supply, water quality, navigation, commercial fisheries, hydropower, recreation opportunities, open space, and agricultural stewardship 8

9 Restoration Concept Development Approach Define ecosystem restoration footprint Consider baseline conditions Establish restoration priorities Coordinate with concurrent planning efforts Analyze physical suitability for habitat restoration Analyze floodplain inundation Analyze acceptability Analyze flood performance 9

10 Example: Paradise Cut 10

11 Restore riparian scrub habitat in interior of bypass to benefit riparian obligate species and minimize roughness to allow floodwater conveyance Setback levees in bypass Setback levee on Stewart Tract as per River Islands restoration plans and restore tidal marsh and freshwater emergent wetlands habitat Maintain floodcompatible agriculture where feasible Selectively breach levee along mainstem San Joaquin River and restore riparian / SRA habitat along channel margin 11

12 Change in Stage Compared to Existing Conditions (Feet) Paradise Cut Bypass Hydraulic Roughness Sensitivity 2 Paradise Cut Roughness Sensitivity Based on 1956 Scaled Events % Scaled Event 110% Scaled Event Manning's n (Roughness Value) 12

13 Paradise Cut Benefits Summary CVFPP Goal Screening Metric Option M-Ag Improve Flood Risk Management Peak Stage reduction for 200-year event for urban areas (feet) 2.5 Inundated floodplain total amount (acres) of 50% flows (i.e., 2-year event) with 14-day or longer duration during December- May N/A Natural bank total length (miles) 2 Promote Ecosystem Functions River meander potential total amount (acres) 519 Shaded riverine aquatic (SRA) cover total length (miles) 2 Riparian Habitat amount total amount in floodways (acres) 587 Marsh/Wetland Habitat Amount - total amount in floodways (acres)

14 Example: Firebaugh Levee Improvements 14

15 Firebaugh Benefits Summary CVFPP Goal Screening Metric Option C Improve Flood Risk Management Promote Ecosystem Functions Flood risk reduction (from a 100-year event) ($ millions) $2.47 (92% reduction) Life risk reduction (annual life loss) 0 Inundated floodplain total amount (acres) of 50% flows (i.e., 2-year event) with 14-day or longer duration during December- May Natural bank total length (miles) River meander potential total amount (acres) 367 Shaded riverine aquatic (SRA) cover total length (miles) 0.3 Riparian Habitat amount total amount in floodways (acres) 384 Marsh/Wetland Habitat Amount - total amount in floodways (acres)

16 Firebaugh Expected Annual Habitat Results 16

17 Lessons Learned and Next Steps 17

18 Lessons Learned Significant multi-benefit opportunities exist to restore floodplain and riparian habitats along the San Joaquin River corridor Opportunities are tempered by hydrologic alterations that limit floodplain inundation Alignment with other programs is key 18

19 Next Steps Draft San Joaquin River Basinwide Feasibility Study in September/October Public Draft 2017 Update to the CVFPP in December Continue to work with project partners on multi-benefit project development and refinement 19

20 The Path Forward Need to change how we think about flood risk management 2017 Update will refine the 2012 CVFPP and provides a holistic path forward to a different approach The refined SSIA enables the State to integrate and prioritize investments in multi-benefit flood risk reduction projects CVFPP will take 30 years to implement 20