Climate Change Vulnerability Assessment and Adaptation Strategy

Purpose and Background

At its May 24, 2018 meeting, the Delta Stewardship Council directed staff to begin preparing a Climate Change Vulnerability Assessment (CCVA) and Adaptation Strategy (AS) for the Sacramento-San Joaquin River Delta and Suisun Marsh. This work will provide critical support to the Council to improve understanding of regionally specific climate change risks and address how Delta communities, infrastructure, and the ecosystem can adapt to future conditions.

The Delta Reform Act (Act) specifies consideration of “the future impact of climate change and sea level rise” in restoration planning (Water Code Section 85066) and identifies a restoration timeline horizon of 2100 (Water Code Section 85302). The Act also notes that the Delta Plan may address “the effects of climate change and sea level rise on the three state highways that cross the Delta” (Water Code Section 85307). More generally, Executive Order B-30-15, signed by Governor Brown in April 2015, requires State agencies to incorporate climate change into planning and investment decisions. Also, agencies are required to prioritize natural infrastructure and actions for climate preparedness and protection of the most vulnerable populations.

Since the Delta Plan was adopted in 2013, research on climate change has advanced significantly, with important implications for the Council as it seeks to further the coequal goals. Climate change is already altering the physical environment throughout the Delta. Over the long term, climate change in the Delta is expected to adversely affect human health and safety, lead to economic disruptions, diminish water supply, degrade water quality, shift ecosystem function and habitat qualities, and make it more difficult for government agencies to provide basic services. Many of these impacts will disproportionately affect disadvantaged communities; including those located within the Delta.

Expected Outcomes

The CCVA and AS will be used to inform potential future Delta Plan amendments and Council implementation activities related to climate change adaptation. It will help the State prioritize future adaptation investments in the Delta and provide a toolkit of information that local government agencies can use in regulatory documents. It will spatially describe what hazards communities are exposed to, and identify adaptation strategies they can implement for each hazard. Most importantly, this work represents a first step to comprehensively outline a framework for adaptation for the Delta region that can be built upon in the future by the Council and others.

Overview and Process

The general project scope reflects statutory requirements of the Delta Reform Act, assets and resources considered in the Delta Plan, and existing Delta Plan policies, recommendations, and performance measures. The project will apply state agency guidance on climate change to the Delta. This will include guidance from the Governor’s Office of Planning and Research, the Ocean Protection Council, the Natural Resources Agency, and the California Coastal Commission for local and regional government engagement and planning.

The project consists of two phases:

Phase 1: Climate Change Vulnerability Assessment (CCVA)

Based on the best available scientific technical information, guidance, and stakeholder engagement, the project will assess climate vulnerability and risk to key sectors, assets and resources, and services. The CCVA will characterize climate change impacts resulting from sea level rise, precipitation and runoff patterns, and air and water temperatures. Asset sectors to be considered include: water supply and flood management infrastructure, water quality, ecosystems, agriculture, cultural resources, buildings and facilities, parks and recreation, transportation, energy and utilities, and human populations, with particular focus on disadvantaged communities. For each asset sector, the CCVA will assess risk of exposure to climate change impacts, sensitivity to climate change, and adaptive capacity and resources to cope with, adapt to, or recover from climate impacts.

Phase 2: Adaptation Strategy (AS)

In this phase, the project will evaluate alternative responses that could be implemented in the Delta region or elsewhere. The Adaptation Strategy will evaluate potential responses and provide a range of policy and management actions that State and local agencies could take related to each asset sector. Adaptation strategies will enable achievement of resilience goals.

Both the VAAS and Adaptation Strategy will identify thresholds for vulnerability, and identify interim adaptation targets between 2020 -2100. Planning horizons may include 2030, 2050, and 2100.

Process and Roles

In addition to the Council, two groups will provide input and guidance to Council staff and consultants throughout the project. A Technical Advisory Committee comprised of experts from public agencies, academic institutions, non-profit organizations, the private sector, and individuals with particular knowledge of climate change, the Delta, and its resources will provide input on key analyses and findings. A Stakeholder Workgroup representing Delta city/county planning or resource management agencies, community organizations, and interested stakeholders will provide local perspectives for the assessment and strategy, building a constituency for implementation.

Engaging with local and regional Delta government agencies and communities is a fundamental objective of the project. Several local agencies have already adopted climate adaptation policies and recommendations, many of which seek regional collaboration on climate change and sea level rise planning (i.e., Solano County, San Joaquin County, Sacramento County, Yolo County, Contra Costa County, San Joaquin Council of Governments, Sacramento Area Council of Governments). Council staff will engage these agencies to collectively identify adaptation strategies that advance state goals for the Delta while improving both local and regional resilience.

Timeline and Key Milestones

Phase 1 of the project began in Spring 2019 and will conclude with a final CCVA in Spring 2020. Phase 2 will begin in Summer 2020 and conclude with an Adaptation Strategy in Summer 2021.


Timeline of Climate Change Vulnerability Assessment and Adaptation Strategy phases. Stakeholder engagement is ongoing throughout phase one and two. Phase one begins in spring 2019 with a vulnerability assessment. It concludes in spring 2020 with a complete vulnerability assessment. Phase two begins in summer 2020 with an adaptation strategy. It concludes in spring 2021 with a complete adaptation strategy. Next, adaptation strategy implementation begins and carries on into the future.


Get Involved!

Subscribe to the Council's listserv distribution list to receive project updates and more.