Sea Level Variations of the United States 1854–2006

National Oceanic and Atmospheric Administration (NOAA) | December 19th, 2009

The United States National Water Level Network (NWLON) was established in the 19th Century to ensure the Nation’s nautical charts, shoreline maps, and elevations relat

The United States National Water Level Network (NWLON) was established in the 19th Century to ensure the Nation’s nautical charts, shoreline maps, and elevations relative to homes, levees, and other coastal infrastructure were accurately referenced to sea level. In support of this mission, NOAA’s Center for Operational Oceanographic Products and Services and its predecessors have determined sea level for the United States since the mid 19th Century. While climate change was not a concern during the mid-1800s, the accurate determination of sea level was critical for navigation and marine boundary determination. To meet these important requirements, technology, procedures, and processes were developed to the highest scientific and engineering standards. At the turn of the 20th Century it was realized that there was a need to account for a rise in sea level and the first National Tidal Datum Epoch was established. Today this Epoch is updated every 20 to 25 years. The Supreme Court recognized these standards and procedures in the landmark 1936 case of Borax, Ltd v. City of Los Angeles when legally defining sea level. Due to those initial efforts and the continued dedication of those charged with the responsibility for monitoring sea level for the United States, we can accurately determine relative (local) mean sea level along the Nation’s coastline today. These observations also play an important role in monitoring change in global sea level. As we monitor change in sea level into the 21st Century, the statement made by Alexander Dallas Bache, the Second Superintendent of the Coast Survey, is as relevant today as when it was stated more than 150 years ago, “It seems a very simple task to make correct tidal observations; but, in all my experience, I have found no observations which require such constant care and attention” (1854). Michael Szabados, Director, Center for Operational Oceanographic Products and Services

Sea-Level Rise for the Coasts of California, Oregon, and Washington: Past, Present, and Future

National Academy of Sciences (NAS) | December 13th, 2012

Second Supplement to State Water Resources Board Bulletin No. 11, San Joaquin County Investigation, Basic Data, Calaveras Unit, 1955-56

California Department of Water Resources (DWR) | April 20th, 1957

Sediment Supply to San Francisco Bay, Water Years 1995 through 2016: Data, trends, and monitoring recommendations to support decisions about water quality, tidal wetlands, and resilience to sea level rise

San Francisco Estuary Institute (SFEI) | June 11th, 2018

Knowledge of the status and trends of sediment supply to San Francisco Bay is critically important for management decisions about dredging, marsh restoration, flood contr

Knowledge of the status and trends of sediment supply to San Francisco Bay is critically important for management decisions about dredging, marsh restoration, flood control, contaminants, water clarity (in relation to primary production), and sea level rise. Several site-specific studies of sediment supply to San Francisco Bay have been conducted, but no synthesis of recent studies is available. The purpose of this report is to synthesize the best available data and knowledge to answer a few of the key study questions related to sediment supply to the Bay.  This synthesis report was prepared jointly by the Regional Monitoring Program for Water Quality in San Francisco Bay (RMP) and the U. S. Geological Survey (USGS) with funding from both organizations. The project is meant to be a step in the development of a more comprehensive sediment management and monitoring strategy for the Bay. 

Selected Federal Water Activities: Agencies, Authorities, and Congressional Committees

Congressional Research Service (CRS) | ?

More than two centuries of federal water resource activity have resulted in a complex web of federal involvement in water resource development, management, protection, an

More than two centuries of federal water resource activity have resulted in a complex web of federal involvement in water resource development, management, protection, and use. As a result, Congress faces challenges related to overlap and gaps in federal water resource activities and in coordination and consistency among federal programs. Further, many federal authorities are discretionary or funded by discretionary appropriations. Consequently, there can be a significant difference between what federal agencies are authorized to do and what they are actually doing, and no one committee in Congress oversees this dichotomy. Although the responsibility for development, management, protection, and allocation of the nation’s water resources is spread among federal, state, local, tribal, and private interests, this report focuses on federal activities related to water and the congressional committees that authorize and oversee these activities. The report covers multiple topics and individual water-related subtopics ranging from water supply and water quality infrastructure to fisheries management and water rights. The report is not exhaustive; instead, the authors have attempted to cover the major federal activities authorized by Congress that affect water resource development, management, protection, and use in the United States. Similarly, the analysis does not cover every aspect of House and Senate committee jurisdiction affecting water issues. For definitive evaluation of committee jurisdictions related to water, the views of the House and Senate Parliamentarian Offices are official. The report covers four general areas, or themes: (1) “Water Resources Development, Management, and Use”; (2) “Water Quality, Protection, and Restoration”; (3) “Water Rights and Allocation”; and (4) “Research and Planning.” The sections addressing these themes are further divided into tables that list topic areas and individual water-related subtopics. For each subtopic, CRS has identified selected federal agencies and activities related to the subtopic, authorities for such activities, and relevant House and Senate committee jurisdictions, as specified in House and Senate rules. Appendixes address considerations in determining House and Senate committee jurisdictions and present the official language from House Rule X and Senate Rule XXV, respectively, which are indicators of congressional jurisdiction over water resources. The report also includes a glossary of abbreviations for federal agencies and House and Senate committees. The nine tables that make up the body of this report underscore the complexity of federal activities affecting water resource development, management, protection, and use in the United States. As apparent throughout these tables, numerous standing committees in the House and the Senate have jurisdiction over various components of federal water policy. The wide range of federal executive responsibilities for water resources reflects comparably complex congressional legislative responsibilities and directives.

SGMA Best Management Practice: Hydrogeologic Conceptual Model

California Department of Water Resources (DWR) | December 23rd, 2016

The objective of this Best Management Practice (BMP) is to assist in the use and development of hydrogeologic conceptual models (HCM). The California Department of Water

The objective of this Best Management Practice (BMP) is to assist in the use and development of hydrogeologic conceptual models (HCM). The California Department of Water Resources (the Department or DWR) has developed this document as part of the obligation in the Technical Assistance Chapter (Chapter 7) of the Sustainable Groundwater Management Act (SGMA) to support the long-term sustainability of California’s groundwater basins. Information provided in this BMP is meant to provide support to Groundwater Sustainability Agencies (GSAs) when developing a HCM in accordance with the Groundwater Sustainability Plan (GSP) Emergency Regulations (GSP Regulations). This BMP identifies available resources to support development of HCMs. This BMP includes the following sections: Objective. The objective and brief description of the contents of this BMP. Use and Limitations. A brief description of the use and limitations of this BMP. HCM Fundamentals. A description of HCM fundamental concepts. Relationship of HCM to other BMPs. A description of how the HCM relates to other BMPs and is the basis for development of other GSP requirements. Technical Assistance. A description of technical assistance to support the development of a HCM and potential sources of information and relevant datasets that can be used to further define each component. Key Definitions. Definitions relevant for this BMP as provided in the GSP and Basin Boundary Regulations and in SGMA. Related Materials. References and other materials that provide supporting information related to the development of HCMs.

SGMA Best Management Practices Framework

California Department of Water Resources (DWR) | December 22nd, 2017

Chapter 7 of the Sustainable Groundwater Management Act (SGMA), in Water Code Section 10729(d), states that, “By January 1, 2017, the department shall publish on its in

Chapter 7 of the Sustainable Groundwater Management Act (SGMA), in Water Code Section 10729(d), states that, “By January 1, 2017, the department shall publish on its internet Web site best management practices for the sustainable management of groundwater.” Prior to the completion of a best management practices (BMPs) document, the Department of Water Resources (DWR) was required to adopt regulations for evaluating groundwater sustainability plans (GSPs), the implementation of GSPs, and coordination agreements by June 1, 2016 (GSP Regulations), and Alternatives.

Sharing Groundwater: A Robust Framework and Implementation Roadmap for Sustainable Groundwater Management in California

Nicholas Institute for Energy, Environment & Sustainability (Duke University) | January 1st, 2017

This working paper offers a framework and roadmap for development of a robust groundwater-sharing system consistent with California’s Sustainable Groundwater Management

This working paper offers a framework and roadmap for development of a robust groundwater-sharing system consistent with California’s Sustainable Groundwater Management Act, which requires communities in priority areas to prepare groundwater sustainability plans. The proposed system draws on global experience. Robustness is its signature feature. Opportunities are maximized by a suite of robust local governance, allocation, and administrative arrangements. Additionally, the proposed system incentivizes innovation, stimulates investment, and facilitates low-cost adjustment to changes in groundwater demand. Among the dynamic components underlying this sharing system are a share register that records ownership and transfers of ownership in the basin’s available shares. These unit shares are fungible; each represents a proportional stake in access to the basin’s groundwater resources. Volumetric allocations are made in proportion to the number of shares held during determined periods throughout the water year. These allocations are recorded in bank-like water accounts, affording account holders an efficient means to manage their resource but also ensuring that they cannot use more than is available. Unused water can be saved for later use. At the start of the transition to the new system, users are given an allocation buffer so that they have flexibility and time to adjust. Those who want to can make quick non-contestable trades at low cost.

Sharpening of cold-season storms over the western United States

Nature Portfolio (Springer Nature) | January 19th, 2023

Winter storms are responsible for billion-dollar economic losses in the western United States. Because storm structures are not well resolved by global climate models, it

Winter storms are responsible for billion-dollar economic losses in the western United States. Because storm structures are not well resolved by global climate models, it is not well established how single events and their structures change with warming. Here we use regional storm-resolving simulations to investigate climate change impact on western US winter storms. Under a high-emissions scenario, precipitation volume from the top 20% of winter storms is projected to increase by up to 40% across the region by mid-century. The average increase in precipitation volume (31%) is contributed by 22% from increasing area coverage and 19% from increasing storm intensity, while a robust storm sharpening with larger increase in storm centre precipitation compared with increase in storm area reduces precipitation volume by 10%. Ignoring storm sharpening could result in overestimation of the changes in design storms currently used in infrastructure planning in the region.

Shifts in the thermal niche of almond under climate change

Climatic Change (Springer) | December 5th, 2017

Delineating geographic shifts in crop cultivation under future climate conditions provides information for land use and water management planning, and insights to meeting

Delineating geographic shifts in crop cultivation under future climate conditions provides information for land use and water management planning, and insights to meeting future demand. A suitability modeling approach was used to map the thermal niche of almond cultivation and phenological development across the Western United States (US) through the mid-21st century. The Central Valley of California remains thermally suitable for almond cultivation through the mid-21st century, and opportunities for expansion appear in the Willamette Valley of western Oregon, which is currently limited by insufficient heat accumulation. Modeled almond phenology shows a compression in reproductive development under future climate. By the mid-21st century, almond phenology in the Central Valley showed ~ 2-week delay in chill accumulation and ~ 1- and ~ 2.5-week advance in the timing of bloom and harvest, respectively. Although other climatic and non-climatic restrictions to almond cultivation may exist, these results highlight opportunities for shifts in the geography of high-value cropping systems, which may influence growers’ long-term land use decisions, and shape regional water and agricultural industry discussions regarding climate change adaptation options.