The Delta Plan

While there are many agencies involved in both the near and long-term management of the Delta, the Sacramento-San Joaquin Delta Reform Act of 2009 (Delta Reform Act) established the Delta Stewardship Council (Council) to create a comprehensive, long-term, legally enforceable plan to guide how multiple federal, state, and local agencies manage the Delta’s water and environmental resources. The 2009 legislation directed the Council to oversee implementation of this plan through coordination and oversight of state and local agencies proposing to fund, carry out, and approve Delta-related activities. It also granted the Council regulatory and appellate authority over certain actions that take place in whole or in part in the Delta and Suisun Marsh, referred to as covered actions.

Since 2010, the Council has developed, amended, and begun implementing the Delta Plan, addressing multiple complex challenges in the process. Much progress has been made, but much remains to be done. Developed to achieve the state’s coequal goals of a reliable statewide water supply and a protected, restored Delta ecosystem in a manner that preserves the values of the Delta as a place, the Delta Plan includes 14 regulatory policies and 95 recommendations. Collectively, these policies and recommendations address current and predicted challenges related to the Delta’s ecology, flood management, land use, water quality, and water supply reliability. The Delta Plan’s policies and recommendations are based on best available science and depend on cooperation and coordination among federal, state, and local agencies.

View the Delta Plan (last amended April 26, 2018) by individual chapters and appendices:



Original Delta Plan (Adopted May 16, 2013)

High Resolution Maps from the Delta Plan

The following thirteen maps are listed in the Delta Plan document using a standard print resolution. These high resolution versions are being made available so that the detailed information on the maps is more easily readable.

  • Figure 1-1 Delta Boundaries (3.16 MB)

    The Sacramento-San Joaquin Delta and Suisun Marsh are referred to throughout the Plan collectively as “the Delta,” unless otherwise specified. The Sacramento-San Joaquin Delta is defined in Water Code section 12220, and Suisun Marsh means the area defined in Public Resources Code section 29101 and protected by Division 19 (commencing with section 29000).

  • Figure 1-2 Delta Plan Study Area - Revised (863 KB)

    The Delta Watershed and Areas Receiving Delta Water - Water from the vast Delta watershed, spanning over 45,000 square miles (30 million acres), fuels both local economies and those in export areas hundreds of miles away.

  • Figure 1-4 The Delta Plan (2.82 MB)

    The map shows the primary area covered by the Delta Plan, including features and uses referred to in the Plan's 14 policies and 73 recommendations.

  • Figure 3-2 Moving and Storing California’s Water (4.97 MB)

    To provide more reliable water supplies despite the state’s hydrologic variability and diverse geography, and also to manage floods during wet years, State, federal, and local agencies have built a vast, interconnected infrastructure system throughout California.

  • Figure 4-6 Habitat Types Based on Elevation, Shown with Developed Areas in the Delta and Suisun Marsh (3.60 MB)

    Opportunities for habitat restoration in the Delta are constrained first and foremost by the elevation of land, which determines the potential of an area to be restored. Much of the Delta has subsided too deeply to restore its original ecological functions.

  • Figure 4-8 Recommended Areas for Prioritization and Implementation of Habitat Restoration Projects (2.82 MB)

    Priority habitat restoration areas are large areas within which specific sites may be identified for habitat restoration based on assessments of land use and other issues addressed through further feasibility analysis.

  • Figure 5-1 Delta Primary & Secondary Zones & Suisun Marsh (2.50 MB)

    The Delta is composed of three areas recognized in California law. The Primary Zone is the largest and includes 490,050 acres at the heart of the Delta (Public Resources Code section 29728). The Secondary Zone includes 247,320 acres surrounding the Primary Zone (Public Resources Code section 29731). Suisun Marsh lies northwest of the Primary Zone, encompassing 106,570 acres (Public Resources Code section 29101) primarily of managed wetland. The Suisun Marsh overlaps the boundary of the Delta by about 4,300 acres.

  • Figure 5-2 Delta Communities (2.63 MB)

    The map shows land uses designated by city and county general plans. Within cities' spheres of influences (SOIs), the map shows land use designations proposed in city general plans, where available. In cases where cities have not proposed land uses within their SOIs, the map shows land uses designated by county general plans.

  • Figure 5-3 Agricultural Land Use in the Delta (4.81 MB)

    Agriculture is among the qualities that define the Delta as a place. The Delta’s initial reclamation created farmland, and ongoing maintenance of its levees and water controls allows for continued farming in the region. Agriculture dominates the Delta landscape and provides the setting for Delta residents’ communities, homes, and job sites.

  • Figure 5-5 State Parks and Other Protected Lands (2.87 MB)

    The map shows the locations of State parks and other protected lands in the Delta. The Delta Protection Commission estimates that about 12 million activity days of recreation occur in the Delta annually (DPC 2012b). Visitors value the wide expanses of open land, interlaced waterways, historic towns, and the lifestyle offered by the Delta.

  • Figure 5-6 Major Delta Resources and Recreation (3.91 MB)

    This map shows the variety and distribution of some of the recreational opportunities in the Delta. The region’s mix of land and water offers di-verse recreation experiences and facilities, including fishing, boating, bird watching, other nature activities, hunting, enjoying restaurants, campgrounds, picnic areas, and historic towns and buildings.

  • Figure 7-3 Levees in the Delta (2.90 MB)

    This map shows the locations of project and non-project levees in the Delta. The project levees begin on the left bank of the Sacramento River at Sherman Island and line most of the riverbanks, as well as the Sacramento River Deep Water Ship Channel and some connecting waterways north to Sacramento and beyond. On the San Joaquin River they line the riverbanks from Old River to Stockton.

  • Figure 7-6 Delta Flood Management Facilities (2.17 MB)

    The map shows flood management resources including flood control bypasses and floodways, along with other floodplains to be protected. It also shows water supply reliability levee projects, flood control project levees and urban non-project levees.

Delta Plan Five-Year Review

To ensure that the Delta Plan evolves appropriately with time, the Delta Reform Act requires that the Council review the Plan at least once every five years, or as the Council deems appropriate. In 2018, the Council began a review of the Plan with three objectives in mind:

  1. to reflect on the successes and challenges of initial efforts across agencies to implement the Plan;
  2. to focus and prioritize the Council’s near-term future efforts to implement the Plan; and
  3. to identify planning topics and emerging issues that may inform future Plan updates.

The purpose of the 2019 Delta Plan Five-Year Review is to consider the Delta Plan’s core elements in light of six years of experience, and to reflect on the successes and challenges of implementing the Delta Plan. By considering the Plan and implementation progress, the Council will be better positioned to develop a roadmap for potential future changes and improvements to Delta Plan content and implementation strategies.

The 2019 Delta Plan Five-Year Review Report will be published in fall 2019 presenting findings from the Delta Plan Five-Year Review process and recommending priority actions for the next five years to strengthen the Plan and its implementation. A draft of this report was presented to the Council for discussion in August 2019.

Delta Plan Amendments

Adopted by the Delta Stewardship Council (Council) in May 2013, the Delta Plan anticipated the need for periodic reviews and updates in response to changing circumstances and conditions in the Sacramento-San Joaquin River Delta. Since its adoption in 2013, the following amendments have been made to the Delta Plan.

  • Performance Measures: When first adopted, the Delta Plan contained preliminary performance measures developed to monitor implementation of its policies and recommendations. The Delta Plan identified the need for the Council to continue to work with scientific, agency, and stakeholder experts to further refine its performance measures. The Council subsequently conducted a rigorous public process and adopted new and refined performance measures in February 2016.
  • Single-Year Water Transfers: Water transfers across the Delta can be an important tool for improving water supply reliability, especially in drought years when some water rights holders may choose to sell a portion of their water supply to areas of the state that are harder hit or are willing to place a greater value on that water. The Council conducted an environmental review and adopted a regulatory amendment in September 2016 that exempts single-year water transfers from regulation under the Delta Plan and simplifies the implementation of these short-term transfers.
  • Conveyance, Storage, and Operations: This amendment includes a series of recommendations that fulfill the Council’s statutory requirement to promote options for water conveyance, storage, and operations of both. Adopted in April 2018, this amendment includes recommendations that the design and implementation of new or improved conveyance infrastructure in the Delta minimize disruptions to transportation and business activities in the Delta, complement the Delta landscape, and are implemented in cooperation with affected communities, local governments, the Delta Protection Commission, and Delta stakeholders.
  • Output and Outcome Performance Measures: In addition to its 123 administrative measures, the Delta Plan’s performance measures include 38 output and outcome measures. The measures were refined based on stakeholder and independent scientific reviews, and they aim to translate programmatic objectives into measurable indicators of progress. They are a vital part of the Council’s adaptive management approach and provide decision-useful information on the status and trends toward the coequal goals. This amendment was adopted in April 2018.
  • Delta Levees Investment Strategy (DLIS): The DLIS is a multiyear project to update the Delta Plan’s 2013 interim priorities, as requested by the legislature, for flood risk reduction and guide the prioritization of state investments in the Delta (more than $700 million since the 1970s) that reduce flood risk and better integrate Delta levees with other Delta actions and statewide flood control. The DLIS was developed with substantial input from the California Department of Water Resources, the Central Valley Flood Protection Board, and local and regional Delta stakeholders. This amendment was adopted in April 2018. The rulemaking process for regulatory components of this amendment is ongoing.

Ecosystem Amendment

In response to the state’s pivot from a habitat conservation plan known as the Bay-Delta Conservation Plan, the Council has worked diligently to begin updating the policies and recommendations in Delta Plan Chapter 4, Protect, Restore, and Enhance the Delta Ecosystem. Currently under development by the Council, this amendment considers past and future effects of climate change and sea level rise, incorporates lessons learned about adaptive management of the Delta ecosystem, identifies best practices for restoration projects, and addresses institutional changes to improve implementation so that species can begin to benefit from these projects as soon as possible.

Through a public process lasting through 2020, the Council will work with partner agencies, stakeholders, and the public to build upon, further refine, and amend Chapter 4 of the Delta Plan. Currently, the chapter includes regulations covering flow, introduction of nonnative invasive species, and criteria for priority restoration sites.

For more information regarding amendments made to the Delta Plan, please contact