February 11, 2020 Overview / Board Policies Strategic Assessments - PowerPoint PPT Presentation

Real Property and Asset Management Committee Item 6a February 11, 2020

Overview / Board Policies Strategic Assessments Management Actions Next Steps Real Property & Asset Management 2 Item #6a February 11, 2020

Rio Vista TyIer TULE Island Brannan Staten RED Island Terminous Island Tract Andrus Grizzly Bay Island BOULDIN Twitchell ISLAND Island Simmons Decker Island Island Ryer WEBB Bradford Island Venice Honker Bay Island TRACT Island Empire Spinner Van Sickle Tract Island Island CHIPPS Sherman ISL. Island West Winter Mandeville Mallard Isl. Sherman Island Franks Island Island Sherman Browns Tract Lake Jersey Medford Island Bethel Island Island Kimball Island Quimby Isl. West Isl. Pittsburg Island Big Break Little Mandeville Antioch MacDonald Hotchkiss HOLLAND Island Island Tract TRACT BACON Oakley ISLAND Mildred Island Veale Tract Palm Tract Jones Tract Brentwood 6 Delta & Suisun Marsh properties Orwood Woodward Tract Island 20,400+ acres (13 sq. miles) 111 structures (houses, farm facilities) Byran Victoria Tract Island Bridges, auto ferry, boat docks, pumps In-Delta Freshwater Pathway Union 3 3 Island

Notice of Preparation Alignment options 1 Central Tunnel Corridor Eastern Tunnel Corridor 1 tunnel up to 6,000 cfs 2 intakes (3,000 cfs each) 2 forebays Intermediate/Southern Pumping plant & South Delta facilities 1. NOP identifies two options (Central and Eastern Corridor; Final choice of potentially feasible alternatives for Draft EIR will be made after receipt of scoping comments 4

Bay Delta Focus on Science & Research Science & Research Conduct applied science Base all actions on comprehensive science System Reliability System Reliability Improve water quality & supply reliability Environmental Secure levees along freshwater pathway Protection & Limit land subsidence Seek emergency response plan approval Ag Sustainability Complete emergency preparedness measures Environmental Protection & Ag Sustainability Advance ecosystem restoration actions Select and finance habitat opportunities Develop sustainable agriculture programs Limit carbon production Reduce climate change risks Real Property & Asset Management Item #6a February 11, 2020 5

Overview / Board Policies Strategic Assessments Management Actions Next Steps Real Property & Asset Management 6 Item #6a February 11, 2020

Landscape Issues & Opportunities P RE -1880 At sea-level None Unknown Peat Sands|Silts|Clays Liquefiable Sands 7

Landscape Issues & Opportunities C URRENT -10 to 30 feet -0.5 to 1.5 inch/yr . + 0.2 to 1.5 inch/yr . below sea-level (-3 to 10 ft. by 2100) (+1 to 10 ft. by 2100) L AND E LEVATION I NCREASED S UBSIDENCE S EA L EVEL - 10 to 30 ft. - 0.5 to 1.5 + 0.2 to 1.5 SEEPAGE inch/yr. inch/yr. Actual sea level in the past 130 years is 0.64 feet 8

Landscape Issues & Opportunities C URRENT -10 to 30 feet -0.5 to 1.5 inch/yr . + 0.2 to 1.5 inch/yr . below sea-level (-3 to 10 ft. by 2100) (+1 to 10 ft. by 2100) L AND E LEVATION I NCREASED S UBSIDENCE S EA L EVEL - 10 to 30 ft. - 0.5 to 1.5 + 0.2 to 1.5 SEEPAGE inch/yr. inch/yr. 9

Landscape Issues & Opportunities F UTURE O PPORTUNITIES Carbon sequestration & Integrated landscape Delta Conveyance & regenerative agriculture management Freshwater Pathway projects projects Levee Improvements Widen crown to allow habitat Soil Accretion . 1 +1 to 2 inch/yr (+ 7 to 14 ft. by 2100) 1 Based on Twitchell Island and other habitat restoration projects 10

Landscape Issues & Opportunities F UTURE O PPORTUNITIES 50% reduction in risk with wetlands 1,2 20% Levee Failure Risk by 2070 15% 10% 5% 0% Staten Bouldin Bacon Jersey 1. Source: “Subsidence and levee failure in the California Delta: A proof -of-concept study demonstrates rice and wetland implementation strategy to reduce probability of failure ” Bachand & Associates, Stillwater Sciences, Hydrofocus, and San Francisco State University 2. The analysis looked at two primary modes of failure -static stability and piping failures; The analysis does not consider changes to the dynamic stability/seismic failure risks, over-topping risks, or ongoing annual levee improvements currently taking place. 11

Landscape Issues & Opportunities F UTURE O PPORTUNITIES … L everaging S uccessful A pproaches Netherlands Bract Tract Louisiana Real Property & Asset Management Item #6a Slide 12 February 11, 2020

System Reliability Delta Conveyance In conjunction with DWR, Delta Conveyance Mitigation developed conceptual plan for Mitigation 4,900 ac. utilizing MWD properties to Ag preservation 14,330 ac. accommodate certain mitigation 1 TOTAL 19,230 ac . MWD Property Available Ongoing discussion with DWR & TOTAL 20,400 ac. Design Construction Authority as potential alignments are revised 1.Acreage based on 2018 Cal WaterFix twin tunnel design; Potential future mitigation for single tunnel approach still to be determined. MWD staff concept not yet analyzed or approved by DCA, DWR, or MWD Board Real Property & Asset Management 13 Item #6a February 11, 2020

System Reliability Bouldin Island – Mitigation Conceptual Plan Fishing Science Access Center Delta Conveyance Managed Wetlands In conjunction with DWR, Delta Conveyance Mitigation developed conceptual plan for Mitigation 4,900 ac. utilizing MWD properties to Ag preservation 14,330 ac. Ag Preservation & Rice accommodate certain mitigation 1 TOTAL 19,230 ac . Regenerative Riparian MWD Property Available Ag Ongoing discussion with DWR & TOTAL 20,400 ac. Tunnel Design Construction Authority as Portal Tidal potential alignments are revised Marsh Native Grasses 1.Acreage based on 2018 Cal WaterFix twin tunnel design; Potential future mitigation for single tunnel approach still to be determined. MWD staff concept not yet analyzed or approved by DCA, DWR, or MWD Board Real Property & Asset Management 14 Item #6a February 11, 2020

System Reliability Delta Conveyance Soil Borings for Tunnel Portal Sites Provided DWR access to conduct geotechnical & environmental investigations 1 1.In the Notice of Preparation released in January 2020, the State indicated two alignment options (central and eastern). Final choice of potentially feasible alternatives for Draft EIR will be made after receipt of scoping comments Real Property & Asset Management DWR Geotechnical Investigation 15 Item #6a February 11, 2020

System Reliability Freshwater Pathway Continuing seismic analyses to better understand levee risks and focus solutions Analyzing new levee void detection monitoring technologies Levee Void Detection Illustration Real Property & Asset Management 16 Item #6a February 11, 2020

Invasive Species Control Environmental Protection Invasive Species Control Working with California Department of Fish & Wildlife on invasive species control Cameras and detection station setup on Bacon Isl. Used to detect if Nutria are presence Coordinating with CDFW & others on use of detection dogs Invasive species control detection dogs Real Property & Asset Management Mel Tucker – Farm security, dog handler 17 Item #6a February 11, 2020

Environmental Protection Invasive Species Control Working with California Fish & Wildlife on invasive species control Cameras and detection station setup on Bacon Isl. Used to detect if Nutria are presence Coordinating with CDFW & others on use of detection dogs Nutria Detection Station – Bacon Island Kyle Beardsley, Nutria Specialist, Cal Dept. of Fish & Wildlife Real Property & Asset Management 18 Item #6a February 11, 2020

Environmental Protection Fishery Research Islands provide a platform Bouldin Island to conduct long-term aquatic research MWD salmon predation study Real Property & Asset Management MWD Salmon Predation Study Item #6a February 11, 2020 19

Environmental Protection Wetlands & Ag Sustainability Research Pilot Concepts Wetlands (tule, rice, etc.) Paludiculturecultivated wetlands Paludiculture Regenerative agriculture Floating peat wetlands Benefits Reduce land subsidence Enhance marginal farm land Regenerative Agriculture Reduce sea-level rise impacts Secure carbon capture credits Enhance habitat restoration Limit herbicide & pesticide usage Bouldin Island Floating Peat Wetland Real Property & Asset Management 20 Item #6a February 11, 2020

Environmental Protection & Ag Sustainability Floating Peat Wetlands From Louisiana to Nova Scotia, and Africa to Netherlands Floating Peat Wetland Research Can restore subsided lands to productive wetlands faster Benefits terrestrial and aquatic species, water quality, etc. MWD initiated research taking place on Bouldin Island Working with DWR, Hydrofocus, UC Davis, UC Berkeley, U.S . Geological Survey, Louisiana State University, Univ. of Montana, etc. Louisiana Floating Peat Wetland Real Property & Asset Management Dr. Chris Swarzenski, USGS Louisiana Water Science Center 21 Item #6a February 11, 2020