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Investing in Our Future
Promoting a Sustainable Sacramento-San Joaquin Delta
The Sacramento-San Joaquin Delta is unlike any other place in California. Along with being the heart of the state’s water delivery system, the estuary is home to more than 35 endangered native plants and animals, dozens of historical communities and hundreds of thousands of acres of farmland. The fertile peat soil of its islands produces $700 million in agricultural crops annually and its ecosystem supports the commercial salmon industry on the West Coast. The Delta is simultaneously a crucial link in statewide water infrastructure, a vital yet fragile ecosystem, an engine of our economy and home to 500,000 people. It’s also a region that has witnessed major land-use and landscape changes over the past centuries.
The Delta was once a vast marshland covered with tules and teaming with wildlife. In the mid-1800s, settlers built levees to drain and reclaim the land and today about 95% of the original wetlands and floodplains are gone. In this highly altered environment, non-native species have thrived, over-running native species. Striped bass, Asian clams and many other invaders, large and small, are either eating the native populations or the foods on which they rely.
Recognizing the importance of stabilizing the Delta and securing our water future, Metropolitan purchased a number of Delta islands in 2016. To make our commitment to state and regional water resources more transparent, Metropolitan’s board officially adopted an updated Bay-Delta Policy Framework in October 2022. As a responsible landowner and conscientious neighbor invested in environmental stewardship, we have committed to science-based watershed management, multi-benefit environmental initiatives and community-based partnerships with local stakeholders on these islands and throughout the region.
The Delta faces many challenges, and Metropolitan is committed to finding workable, cooperative solutions. Metropolitan-owned lands in the Delta – Webb Tract, Bacon Island, Bouldin Island and Holland Tract – enable us to explore cooperative approaches to improve the declining ecosystem and promote water reliability. Consistent with our board-adopted Bay-Delta policy framework, we contribute to research and science-based watershed management that improves water quality and reliability, restores native habitat in support of protected and endangered species and promotes sustainable agricultural practices. We’re also studying climate change risks, managing peat soils to reduce carbon emissions and strengthening levees.
We are partnering with state and federal agencies, technical experts, academia and environmental organizations to develop and participate in the studies and projects highlighted below.
Collaborative, multi-benefit projects on Metropolitan's Delta island properties have focused on land use adaptation and habitat restoration opportunities, subsidence reversal efforts and promoting resilience against climate change while mitigating carbon emissions.
Delta Islands Adaptation Planning Project, Bouldin Island
Funded by the state’s Prop 1 grant, this project on Bouldin Island includes a mosaic of land uses for reversing subsidence and promoting sustainable agricultural practices, carbon sequestration, greenhouse gas reductions, water quality improvements and habitat restoration
Multi-benefit Landscape Restoration, Webb Tract
A $20.9 million grant awarded by the Delta Conservancy will fund construction of wetlands and rice fields on Webb Tract to encourage native vegetation and enhance ecosystem benefits.
While the project supports the conservation goals established by the State’s 30x30 Initiative, it will not provide mitigation for existing and proposed projects, including the Delta Conveyance Project.
Floating Wetlands Research, Bouldin Island
This pilot project on Bouldin Island, a partnership between Metropolitan, DWR, the UC Davis Center for Watershed Sciences and other entities, is studying floating peat wetlands, which historically existed in the Delta. If these floating wetlands can be re-established, it could improve the ecosystem and reduce the risk of levee failures.
Delta Smelt Pilot Propagation Study
This research examines the role of environmental conditions and life stage on the survival of liberated cultured Delta smelt and the role for semi-natural ponds on Metropolitan’s Delta Islands to support successful supplementation.
Photo courtesy of DWR
Salmon Predation and Survival Rate Studies
Metropolitan has provided access to its Delta islands to support a number of scientific studies investigating survival rates of juvenile Chinook salmon, an endangered native species to the region, in relation to the increasing presence of non-native predators such as the largemouth bass and proliferation of non-native submerged aquatic vegetation.
“A healthy, thriving ecosystem in the Delta helps deliver a wide range of benefits for our water supplies, threatened species and the local Delta communities. We are committed to working collaboratively to sustain this region that is so critical to our entire state.”
— Metropolitan General Manager Adel Hagekhalil
Partnering to Achieve Restoration
Over the last three decades, federal, state and local agencies, as well as nongovernmental agencies, have worked together, contributing hundreds of millions of dollars to projects that help restore and preserve the Delta’s ecosystem. In addition to projects on the islands it owns, Metropolitan partners with other agencies and organizations on projects that benefit the Delta’s natural systems.
California EcoRestore
Metropolitan participates in this multi-agency initiative led by the California Department of Water Resources that aims to advance more than 30,000 acres of critical habitat restoration and enhancements in the Delta, Suisun Marsh and Yolo Bypass region to support the Delta’s long-term health and its native fish and wildlife species through cutting-edge science and shared expertise and investment.
Sutter Bypass Restoration
Metropolitan engages in scientific studies with staff at academic institutions and other partner and water agencies to coordinate research on habitat restoration and grant opportunities in the Sutter Bypass, an approximately 14,000-acre floodplain that helps sustain local ecosystem processes, groundwater recharge, food web production and habitat for aquatic species.
Yolo Bypass Restoration
Metropolitan supports habitat restoration work in the Yolo Bypass Wildlife Area, a 60,000-acre floodplain that protects Sacramento from flooding and provides important habitat to migrating waterfowl and endangered fish populations. Recent improvements added 220 acres of managed wetlands, increased the productivity of existing wetlands, improved wildlife-friendly management of rice fields, reduced on-site flooding and increased and improved public recreational and educational access to the area.
Bay Delta Interagency Scientific Coordination
Metropolitan participates in the Delta Stewardship Council’s Delta Plan Interagency Implementation Committee’s Restoration Subcommittee, Science Funding and Governance Initiative, and Science Enterprise Subcommittees to identify and implement restoration activities in the Delta that promote natural and human communities, resiliency to stressors, adaptation to change, and recreational accessibility.
Additional Bay-Delta Resources
Multi-benefit Landscape Restoration on Webb Tract (April 2023)
Bay-Delta Policy Framework and Objectives (October 2022)