Sacramento and San Joaquin Basins Climate Impact Assessment

U.S. Bureau of Reclamation (USBR) | September 8th, 2014

Through West-Wide Climate Risk Assessments (WWCRAs) conducted under that program, Reclamation is conducting reconnaissance-level assessments of risks to water supplies an

Through West-Wide Climate Risk Assessments (WWCRAs) conducted under that program, Reclamation is conducting reconnaissance-level assessments of risks to water supplies and related resources in eight major Reclamation river basins in the Western United States. This report presents the results of the Sacramento and San Joaquin Climate Impact Assessment (SSJIA), which addresses impacts in two of these major basins in California. The SSJIA also includes the Tulare Lake Basin in the southern part of the Central Valley of California; part of the Trinity River watershed from which some water is diverted into the Central Valley; and a portion of California’s central coast region where Central Valley Project (CVP) and State Water Project (SWP) water supplies are delivered. The water supplies and demands analyzed in the SSJIA include CVP water users, SWP water users, and the other non-project water users in the study area. Included in the report is an overview of the current climate and hydrology of California’s Central Valley (Sacramento, San Joaquin and Tulare Lake Basins), an analysis of observed trends in temperature and precipitation over historical record, and a comparison of these trends to future water operation projections not considering climate change. The report then presents hydrologic projections developed from global climate models to evaluate the ways that projected climatic and hydrologic changes could impact water availability and management and water demands within the Sacramento, San Joaquin and Tulare Lake basins. The SSJIA analyzes potential impacts of climate change under a current trends projection of future urban growth considering the conversion of agricultural to urban land use and assuming the continuation of current crop types in the Central Valley. Finally, the SSJIA assesses risks to the eight major resource categories identified in the SWA by looking at a range of climate futures and attempting to book-end future uncertainties.

Sacramento and San Joaquin Rivers Basin Study: Technical Report

U.S. Bureau of Reclamation (USBR) | March 8th, 2016

This Technical Report supplements the Sacramento and San Joaquin Basins Study Report (Summary Report) by providing greater detail on the technical approach employed in th

This Technical Report supplements the Sacramento and San Joaquin Basins Study Report (Summary Report) by providing greater detail on the technical approach employed in this analysis, including assumptions, methodologies and results not included in this Report. See the Summary Report for a discussion of the Basin Study program context (Section 1), basin settings (Section 2), and historic and projected climate (Section 2). Figure P-1 shows the geographic area included in the study. The Central Valley and regions that depend on the Sierra Nevada and Coast Range mountains for water have been facing rising demands for water from rapidly increasing populations, changes in land use, and growing urban, agricultural and environmental demands. These demands already exceed the capacity of the existing water management system to supply adequate water—especially in droughts like the one California is now experiencing. Future climate changes are likely to increase the challenges that have already occurred in the 20th century. This Basins Study builds on previous climate impact assessments and addresses both the potential impacts of climate and socioeconomic changes and explores how these challenges might be addressed (see Section 1. Introduction of the Summary Report).

Sacramento River Temperature Task Group Annual Report of Activities, October 1, 2015 through September 30, 2016

Delta Stewardship Council (Delta Council) | October 31st, 2016

Safeguarding California Plan: 2018 Update – California’s Climate Adaptation Strategy

California Natural Resources Agency (CNRA) | January 1st, 2018

Globally, California leads in efforts to avoid the worst effects of climate change by reducing greenhouse gas emissions. Still, the impacts of climate change a

Globally, California leads in efforts to avoid the worst effects of climate change by reducing greenhouse gas emissions. Still, the impacts of climate change are already being felt in California and are disproportionately impacting the state’s most vulnerable populations. The accelerating rate of climate change in this century will likely exceed that experienced by California’s native peoples over past millennia. Already these changes have rendered our state’s 117 years of weather-related record-keeping unreliable as predictors of future events. We know that California’s climate is changing, and responsible institutions must plan for and take action to address current and future climate impacts.

Safeguarding California: Implementation Action Plans

California Natural Resources Agency (CNRA) | April 8th, 2016

Science tells us that the Earth’s climate is changing, and human activity is the primary cause of these changes. Climate disruption drives extreme weather events such a

Science tells us that the Earth’s climate is changing, and human activity is the primary cause of these changes. Climate disruption drives extreme weather events such as coastal storm surges, drought, wildfires, floods and heat waves. As Californians are painfully aware, these events can be devastating. It is imperative that we act to reduce the vulnerability and increase the resilience of our residents, communities and natural resources. California released its first comprehensive plan for adapting to climate change in 2009, and updated that strategy with the 2014 report Safeguarding California: Reducing Climate Risk. Since 2009, California has experienced several of the most extreme natural events in its recorded history: severe drought, an almost non-existent Sierra Nevada winter snowpack, five of the top 20 largest forest fires ever recorded in the state in terms of acreage burned, and back-to-back years of the hottest average temperatures. According to the California Climate Tracker, the winter average minimum temperature of 2014-15 for the Sierra Nevada region was 32.1 degrees Fahrenheit, the first time this value was above water’s freezing point in 120 years of record-keeping. As greenhouse gas emissions continue to accumulate and climate disruption grows, such destructive events will become more frequent. The historical record, which once set our expectations for the traditional range of weather and other natural events, is becoming an increasingly unreliable predictor of the conditions we will face in the future. This document details how California will build the resilience of our residents, communities, and ecosystems to the emerging impacts of climate change. The ten implementation plans presented here represent a master blueprint for executing actions recommended in the 2014 report Safeguarding California: Reducing Climate Risk, as called for in Governor Brown’s April 2015 Executive Order (B-30-15).

Safeguarding California: Reducing Climate Risk An update to the 2009 California Climate Adaptation Strategy

California Natural Resources Agency (CNRA) | July 31st, 2014

California and the world’s climate are changing, posing an escalated threat to health, well-being, nature, and property. Extreme weather, rising sea levels, shifting sn

California and the world’s climate are changing, posing an escalated threat to health, well-being, nature, and property. Extreme weather, rising sea levels, shifting snowpack, among other impacts will touch every part of peoples’ lives in the next century. Planning key actions now will help us lessen impacts and cope with changes. Many aspects of the environment face historic displacement. In government at every level, we must work together to safeguard our state. And ultimately, each and every one of us needs to take steps to reduce our own impacts and increase our resilience in the future. The Safeguarding California Plan provides policy guidance for state decision makers, and is part of continuing efforts to reduce impacts and prepare for climate risks. This plan, which updates the 2009 California Climate Adaptation Strategy, highlights climate risks in nine sectors in California, discusses progress to date, and makes realistic sector-specific recommendations. California is a leader in the global effort to fight climate change. The state is pursuing a broad, integrated strategy to reduce greenhouse gas emissions and build the foundation for a new clean energy economy. While these efforts will reduce the magnitude and impact of climate change, they will not prevent it from occurring. Given the potential impacts and the long-term nature of effective planning, it is only prudent to begin preparing for these impacts. Actions needed to meet these challenges will not be cheap, but will cost far less than taking no action. Every step that we take today helps save valuable resources in the future. To that end, the plan details 11 current efforts already underway. Right now, more extreme fires, storms, and heat waves are costing lives and property damage. State of the art modeling shows that a single extreme winter storm in California could cost on the order of $725 billion – with total direct property losses of nearly $400 billion and devastating impacts to California’s people, economy and natural resources. The health and fiscal consequences are dire. Climate change poses a threat not just to lives and health, but the financial resources of governments and the insurance industry. More broadly – and likely more costly – are rising seas that threaten our coast, while disappearing snowpack in the Sierra Nevada presents new challenges for our state’s water management. In the near term, we must take practical, affordable steps to maintain our water, power, and transportation infrastructure, and plan for longer term actions as well.

San Diego Basin Study

U.S. Bureau of Reclamation (USBR) | August 15th, 2017

The purpose of the San Diego Basin Study (Basin Study) is to determine potential climate change impacts on water supplies and demands within the San Diego region and to i

The purpose of the San Diego Basin Study (Basin Study) is to determine potential climate change impacts on water supplies and demands within the San Diego region and to identify how potential adaptation strategies could mitigate supply shortages. The intention of Task 2.3 is to create a computer simulation model to forecast supply and demand imbalances under current and future conditions, and current and future demands under a baseline water system infrastructure in the Study Area. This Interim Report describes the methodologies and findings of this Task. 

San Diego County Ecosystems: Ecological Impacts of Climate Change on a Biodiversity Hotspot

California Energy Commission (CEC) | August 27th, 2018

The diverse ecosystems, habitats, plants, and animals in the San Diego County region will be impacted by climatic shifts in multifold ways due to current and future vari

The diverse ecosystems, habitats, plants, and animals in the San Diego County region will be impacted by climatic shifts in multifold ways due to current and future variability, along with other factors including habitat loss and fragmentation, land use shifts, and changing fire regimes. While home to a major metropolitan area, San Diego County still hosts expanses of native and preserved habitats where management and conservation action could be greatly enhanced through science-based assessments and planning for climate change and increased climate variability. Projections of climate change in the region include warming by 4-9° F on average, and a 15-25% decrease in fall and spring precipitation with an increase in variability resulting in more frequent and intense droughts punctuated by increasingly rare yet extreme precipitation and flooding events. In addition, an increase in fire events and potential lessening of coastal marine influence may also affect San Diego’s ecosystems. Climate warming superimposed upon the pronounced spatially-varying temperature in the San Diego region will likely be associated with range shifts for many species resulting in novel community assemblages and biotic interactions and could create phenological mismatches. More frequent and intense heat waves may disproportionately affect younger age classes and reduce reproductive and survival rates of species sensitive to temperature extremes. With increasingly variable precipitation, drought may occur more frequently due to increased occurrence of dry days and could intensify because of warmer temperatures. Since drought disproportionately affects some species, these projected changes may cause structural changes to ecosystems. Santa Ana winds, occurring during increasingly dry fall months, would create ideal fire conditions. Coastal low clouds and fog along San Diego’s coast buffer this zone from the effects of warming and drying through shading and cooling. Although these marine stratus clouds will remain a presence, future changes in this phenomenon are uncertain. The spatial and temporal scales at which climate variations and change operate must be considered to build resilience into natural systems. Effective conservation actions will need to build on ongoing efforts focused on landscape-scale planning rather than more traditional single-species approaches. To carry this out will require cross-jurisdictional, multidisciplinary collaboration by scientists, policy-makers, planners, land managers, and the broader conservation community, which has a decades-long history of accomplishment in San Diego County.

San Francisco Bay Shore Inventory Mapping for Sea Level Rise Planning

San Francisco Estuary Institute (SFEI) | April 5th, 2016

With rising sea levels and the increased likelihood of extreme weather events, it is important for regional agencies and local municipalities in the San Francisco Bay Are

With rising sea levels and the increased likelihood of extreme weather events, it is important for regional agencies and local municipalities in the San Francisco Bay Area to have a clear understanding of the status, composition, condition, and elevation of our current Bay shore, including both natural features and built infrastructure. The purpose of this Bay shore inventory is to create a comprehensive and consistent picture of today’s Bay shore features to inform regional planning. This dataset includes both structures engineered expressly for flood risk management (such as accredited levees) and features that affect flooding at the shore but are not designed or maintained for this purpose (such as berms, road embankments, and marshes). This mapping covers as much of the ‘real world’ influence on flooding and flood routing as possible, including the large number of non-accredited structures. This information is needed to: 1. identify areas vulnerable to flooding; 2. identify adaptation constraints due to present Bay shore alignments; and 3. suggest opportunities where beaches, wetlands, and floodplains can be maintained or restored and integrated into flood risk management strategies.

San Francisco Bay Shore Inventory: Mapping for Sea Level Rise Planning

San Francisco Estuary Institute (SFEI) | July 1st, 2016

With rising sea levels and the increased likelihood of extreme weather events, it is important for regional agencies and local municipalities in the San Francisco Bay Are

With rising sea levels and the increased likelihood of extreme weather events, it is important for regional agencies and local municipalities in the San Francisco Bay Area to have a clear understanding of the status, composition, condition, and elevation of our current Bay shore, including both natural features and built infrastructure. The purpose of this Bay shore inventory is to create a comprehensive and consistent picture of today’s Bay shore features to inform regional planning. This dataset includes both structures engineered expressly for flood risk management (such as accredited levees) and features that affect flooding at the shore but are not designed or maintained for this purpose (such as berms, road embankments, and marshes). This mapping covers as much of the ‘real world’ influence on flooding and flood routing as possible, including the large number of non-accredited structures. This information is needed to: identify areas vulnerable to flooding. identify adaptation constraints due to present Bay shore alignments; and suggest opportunities where beaches, wetlands, and floodplains can be maintained or restored and integrated into flood risk management strategies. The primary focus of the project is therefore to inform regional planners and managers of Bay shore characteristics and vulnerabilities. The mapping presented here is neither to inform FEMA flood designation nor is it a replacement for site-specific analysis and design. The mapping consists of two main elements: Mapping of Bay shore features (levees, berms, roads, railroads, embankments, etc.) which could affect flooding and flood routing. Attributing Bay shore features with additional information including elevations, armoring, ownership (when known), among others. SFEI delineated and characterized the Bay shore inland to 3 meters (10ft) above mean higher high water (MHHW) to accommodate observed extreme water levels and the commonly used range of future sea level rise (SLR) scenarios. Elevated Bay shore features were mapped and classified as engineered levees, berms, embankments, transportation structures, wetlands, natural shoreline, channel openings, or water control structures. Mapped features were also attributed with elevation (vertical accuracy of <5cm reported in 30 meter (100ft) segments from LiDAR derived digital elevation models (DEMs), FEMA accreditation status, fortification (e.g., riprap, buttressing), frontage (e.g., whether a feature was fronted by a wetland or beach), ownership, and entity responsible for maintenance. Water control structures, ownership, and maintenance attributes were captured where data was available (not complete for entire dataset). The dataset was extensively reviewed and corrected by city, county, and natural resource agency staff in each county around the Bay. This report provides further description of the Bay shore inventory and methods used for developing the dataset. The result is a publicly accessible GIS spatial database.