Delta Adapts: Creating a Climate Resilient Future

June 2021 - Delta Adapts: Creating a Climate Resilient Future. June 2025 - Delta Adapts: Creating a Climate Resilient Future.

About

Climate change poses growing risks to California's water supply, ecosystem, wildlife, communities, economy, and more. In the Sacramento-San Joaquin Delta, it threatens water quality, stresses native species, and increases the strain on levees that protect residents, farmland, and public utilities from flooding. To reduce the Delta’s vulnerability, the region urgently needs science-based adaptation strategies and decisions.

Since 2018, the Delta Stewardship Council has led a two-part climate initiative called “Delta Adapts,” which takes a comprehensive, regional approach to climate resiliency that cuts across regional boundaries and commits to collaboration across state, local, and regional levels. The initiative began with a climate change Vulnerability Assessment for the Delta and Suisun Marsh, published in June 2021.

  • Read this information sheet for a summary of the Delta Adapts initiative and the Vulnerability Assessment.

In June 2025, the Council adopted the Adaptation Plan, which, along with supporting documentation, details strategies and actions the Council and its partners can take to adapt to climate change in the Delta. Lea el resumen ejecutivo en Español.

  • Read this information sheet or a summary of the strategies included in the Adaptation Plan.

Navigating the Adaptation Plan

Delta Adapts presents multiple entry points to the Adaptation Plan and proposed adaptation strategies. Readers who are interested in a particular focus area can directly access the following chapters.

  • Flood Risk Reduction (Chapter 4)
  • Ecosystem (Chapter 5)
  • Agriculture (Chapter 6)
  • Water Supply Reliability (Chapter 7)

If you are interested in receiving high-level updates on Delta Adapts, please subscribe to receive email announcements from the Council. For any questions, please email climatechange@deltacouncil.ca.gov.

Adaptation Plan Process and Timeline

Developing the Adaptation Plan

A timeline of the Delta Stewardship Council’s Delta Adapts process.

The Adaptation Plan has been informed by a robust engagement process with diverse interests, findings from the Vulnerability Assessment, and other literature and existing adaptation plans (see graphic below or this information sheet for more details).

This graphic outlines the process for the Delta Adapts initiative, beginning with the Vulnerability Assessment that was completed in 2021. The Vulnerability Assessment found there will be: more flooding; climate change will impact Delta residents disproportionately; less reliable Delta water exports; periodic decreases in water quality for in-Delta users; increased loss and stress on ecosystems; and decreased agricultural yields. For development of the Adaptation Plan, Council staff engaged with the following groups in several formats between 2021 and 2025: stakeholder work group meeting series; technical focus group meeting series; environmental justice and tribal justice interviews; farmer and landowner interviews; 2023 Adaptive Management Forum; focus group member survey; Delta Residents Survey result application; Delta Restoration Forum; 2023 Tribal Listening Session; 2024 Tribal Roundtable; and targeted community outreach and community workshops. Engagement with the Environmental Justice Expert Group, informal and formal tribal consultations, engagement with 24 community-based organizations, and regular briefings with state, local, flood, and water agencies has been ongoing. There was a 90-day public comment period and tribal consultation period as well as a Drop-In discussion in January for the public review draft. The draft Adaptation Plan includes a set of adaptation strategies, recommended implementation leads and partners, and governance best practices.

Past Accomplishments

Publishing the Vulnerability Assessment

The Council adopted the Delta Adapts Vulnerability Assessment in 2021. The Vulnerability Assessment evaluates the vulnerability of the Delta and Suisun Marsh to climate impacts through the end of the century. Refer to this handout for a summary of key vulnerabilities identified in the Vulnerability Assessment.

As part of the Vulnerability Assessment, the Council created a custom social vulnerability index to identify areas within the Delta that are socially vulnerable to climate change impacts. See the Delta Social Vulnerability Index interactive map for more detail on the factors considered in the index or the identified areas.

The Council also created a flood explorer map which allows users to select various climate scenarios to visualize areas exposed to flooding.

Other resources include:

Background

  • The Sacramento-San Joaquin Delta Reform Act, chaptered in 2009, mandates the consideration of “the future impact of climate change and sea level rise” (Wat. Code, § 85066.) in restoration planning and identifies a restoration timeline horizon of 2100. (Wat. Code, § 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.” (Wat. Code, § 85307.)
  • Executive Order B-30-15, signed by Governor Brown in April 2015, requires State agencies to incorporate climate change into their planning and investment decisions. It also requires agencies’ planning and investment decisions to be guided by prioritizing natural infrastructure and protecting the most vulnerable populations.
  • The Delta Plan is California’s roadmap for the region, supporting the coequal goals of a reliable statewide water supply and resilient Delta ecosystem. Research on climate change has advanced significantly since the Delta Plan’s adoption, with important implications for the Council as it seeks to fulfill its mission of furthering the coequal goals, which are sure to be continuously impacted by climate change.

As an agency of experienced planners, engineers, scientists, and communicators, the Council is uniquely equipped – and authorized – to steward the region toward resiliency. The Council has adopted regulations that support statewide water supply reliability and Delta ecosystem resiliency and has the resources needed to guide climate adaptation in the region. Through its strong working relationships with government agencies on the federal, State, regional, and local levels, the Council can influence action in the Delta to improve its resilience over time and communicate the statewide implications of anticipated regional impacts.

The Council’s role in Delta Adapts has three core elements:

  1. The convener bringing various partners together to work as part of a broader team,
  2. The initiator of the regional planning process, and
  3. An active participant collaborating with a robust group of experts and interested partners.