2022 Drought Plan Klamath Project, Oregon-California Interior Region 10, California-Great Basin

U.S. Bureau of Reclamation (USBR) | April 29th, 2022

The Klamath Project (Project) delivers water for irrigation purposes to up to approximately 230,000 acres in southern Oregon and northern California when water is availab

The Klamath Project (Project) delivers water for irrigation purposes to up to approximately 230,000 acres in southern Oregon and northern California when water is available. The Project relies upon several primary water sources to meet irrigation demands including water from Upper Klamath Lake (UKL), Clear Lake Reservoir, and Gerber Reservoir, and from the Klamath and Lost rivers. The Project’s water supplies (Project Supply or Supplies) have been impacted by the severe drought conditions currently affecting the Klamath Basin in southern Oregon and northern California. This 2022 Drought Plan describes the background for and the process of allocating the available Project Supply during the 2022 spring/summer irrigation season (April 15 through September 30, 20222), consistent with the contract priorities that exist within the Project.

2022 Drought Response Operations Plan

U.S. Bureau of Reclamation (USBR) | April 20th, 2022

2023 Annual Report on the Salton Sea Management Program

California Natural Resources Agency (CNRA) | March 31st, 2023

2022 was a year of visible progress and momentum for the Salton Sea Management Program (SSMP) and partners. The first large-scale restoration project in the Sea’s histo

2022 was a year of visible progress and momentum for the Salton Sea Management Program (SSMP) and partners. The first large-scale restoration project in the Sea’s history achieved major construction milestones, while community-oriented projects and vegetation enhancement made headway around the Sea in collaboration with state, federal and local entities.

2023 Water Resilience Portfolio Progress Report

California Natural Resources Agency (CNRA) | October 31st, 2023

2025 Annual Report on the Salton Sea Management Program

California Natural Resources Agency (CNRA) | March 31st, 2025

The State's Salton Sea restoration and management efforts continued to show significant, demonstrable progress in 2024 – achieving key milestones and accelerating the p

The State's Salton Sea restoration and management efforts continued to show significant, demonstrable progress in 2024 – achieving key milestones and accelerating the pace of critical project delivery functions. With new federal funding, the Salton Sea Management Program (SSMP) broke ground to expand what was already the largest restoration project in the Sea’s history, and further expansion is being initiated to suppress dust and restore habitat on up to 9,000 acres at the south end of the Sea. In other areas along the Sea, over 1,300 acres — spanning roughly five miles of shoreline — now host native vegetation recently planted to suppress dust over the coming decades.

A changing framework for urban water systems

American Chemical Society (ACS) | May 8th, 2013

Urban water infrastructure and the institutions responsible for its management have gradually evolved over the past two centuries. Today, they are under increas

Urban water infrastructure and the institutions responsible for its management have gradually evolved over the past two centuries. Today, they are under increasing stress as water scarcity and a growing recognition of the importance of factors other than the cost of service provision are forcing a reexamination of long-held ideas. Research and development that supports new technological approaches and more effective management strategies are needed to ensure that the emerging framework for urban water systems will meet future societal needs

A Community Guide for Evaluating Future Urban Water Demand

Pacific Institute | August 31st, 2016

A Community Guide for Evaluating Future Urban Water Demand provides communities, environmental groups, ratepayer advocates, and anyone interested in sustainable water sup

A Community Guide for Evaluating Future Urban Water Demand provides communities, environmental groups, ratepayer advocates, and anyone interested in sustainable water supply planning with the knowledge and tools they need to understand water demand forecasts. Communities across the U.S. are faced with decisions about how to meet the needs of a growing population. To help make these decisions, water utilities often rely on forecasts that project water use 20 or 30 years into the future, consistent with the amount of time it takes to develop new supply infrastructure, such as desalination plants or reservoirs. For much of the 20th century, water use in American cities grew in proportion to population and the economy. Since the 1980s, however, water use in communities across the United States has remained steady or declined despite continued population and economic growth, due to improved water conservation and efficiency and structural changes in the American economy. While the water sector has undergone a fundamental transformation, the practice of water demand forecasting has been slow to keep pace. Water suppliers routinely overestimate future water demand based on often overstated estimates of population and economic growth and underestimates of the effects of water conservation and efficiency improvements. These inflated estimates of future water needs can result in unneeded water supply and treatment infrastructure, higher costs to ratepayers, and unnecessary environmental impacts. The guidebook explains how water utilities forecast long-term water demand and reviews some of the approaches and methods commonly used by utilities and consultants. It also provides a set of best practices that can be used to create more accurate and robust long-range water demand forecasts. Some of these best practices include accounting for water conservation and efficiency improvements and land use changes, as well as ensuring transparency and meaningful stakeholder engagement.

A Delta Renewed: A Guide to Science-Based Ecological Restoration in the Sacramento-San Joaquin Delta

San Francisco Estuary Institute (SFEI) | November 1st, 2016

A Delta Renewed and the larger Delta Landscapes project are part of an ongoing effort to address these critically important challenges. They provide guidance for restora

A Delta Renewed and the larger Delta Landscapes project are part of an ongoing effort to address these critically important challenges. They provide guidance for restoration that renews critical functions over time without having major negative impacts on the current human enterprise in the Delta area and on other areas dependent on its services. The idea is to determine the most efficient ways to recover Delta functioning so that human benefits are maintained, while investing in process-based recovery of landscape functions. The scientists working on this project assume that this goal is best achieved if we can understand how the Delta functioned before major European modification. We can then use that knowledge as a guide to developing a diverse portfolio of habitats and connections that might sustain native species, and the attributes of a healthy Delta into the future. The effort to reconstruct the Delta of the early 1800s has been challenging, but is now completed. The next step is to devise management scenarios that will recover important functions and native species where possible. There is no intent to try to recreate the Delta of the past. That is impossible without sacrificing our objective of maintaining and even improving the human enterprises now present. What is essential now is to obtain general agreement among all of the stakeholders, which includes all citizens of California, that the Delta should be managed for the benefit of people and wildlife in a sustainable way. Given the uncertainties inherent in any large-scale reconciliation effort, there is a real need to appreciate the complex interactions and inter-dependencies that characterize the various components of the Delta landscape. There is also a need to understand the uncertainties of future climate change and to recognize the diversity of needs among our fellow citizens. Our hopes for success will ultimately depend on generating a spirit of cooperation for the common good. It won’t be easy, but the stakes are high. The Delta Landscapes project is dedicated to that goal.

A freshwater conservation blueprint for California: prioritizing watersheds for freshwater biodiversity

Society for Freshwater Science | April 18th, 2018

Conservation scientists have adapted conservation planning principles designed for protection of habi- tats ranging from terrestrial to freshwater ecosystems. We

Conservation scientists have adapted conservation planning principles designed for protection of habi- tats ranging from terrestrial to freshwater ecosystems. We applied current approaches in conservation planning to prioritize California watersheds for management of biodiversity. For all watersheds, we compiled data on the pre- sence/absence of herpetofauna and fishes; observations of freshwater-dependent mammals, selected invertebrates, and plants; maps of freshwater habitat types; measures of habitat condition and vulnerability; and current manage- ment status. We analyzed species-distribution data to identify areas of high freshwater conservation value that op- timized representation of target taxa on the landscape and leveraged existing protected areas. The resulting priority network encompasses 34% of the area of California and includes ≥10% of the geographic range for all target taxa. High-value watersheds supported nontarget freshwater taxa and habitats, and focusing on target taxa may provide broad conservation value. Most of the priority conservation network occurs on public lands (69% by area), and 46% overlaps with protected areas already managed for biodiversity. A significant proportion of the network area is on private land and underscores the value of programs that incentivize landowners to manage freshwater species and habitats. The priority conservation areas encompass more freshwater habitats/ha than existing protected areas. Land use (agriculture and urbanization), altered fire regimes, nonnative fish communities, and flow impairment are the most important threats to freshwater habitat in the priority network, whereas factors associated with changing climate are the key drivers of habitat vulnerability. Our study is a guide to a comprehensive approach to freshwater conservation currently lacking in California. Conservation resources are often limited, so prioritiza- tion tools are valuable assets to land and water managers.

A Guide to Ordinary High Water Mark (OHWM) Delineation for Non-Perennial Streams in the Western Mountains, Valleys, and Coast Region of the United States

U.S. Army Corps of Engineers (USACE) | August 14th, 2014

Federal regulations define the ordinary high water mark (OHWM) as “that line on the shore established by the fluctuations of water and indicated by physical cha

Federal regulations define the ordinary high water mark (OHWM) as “that line on the shore established by the fluctuations of water and indicated by physical characteristics such as a clear, natural line impressed on the bank, shelving, changes in the character of soil, destruction of terrestrial vegetation, the presence of litter and debris, or other appropriate means that consider the characteristics of the surrounding areas” (U.S. Congress 1986). Under Section 404 of the Clean Water Act (CWA), the OHWM defines the lateral extent of federal jurisdiction in non-tidal waters of the United States (WoUS) in the absence of adjacent wetlands (U.S. Congress 1977). Thus, accurate and consistent OHWM delineation practices are essential for proper implementation of the CWA. The dynamic nature of stream systems and fluvial processes presents challenges for OHWM delineation. Natural sources of variability in river and stream systems (e.g., climate, sediment supply, landscape position, etc.) are compounded by direct and indirect anthropogenic sources of variability (e.g., watershed alteration, dam emplacement and removal, climate change, etc.). Thus, it is challenging to impose a consistent measure of “ordinary” high flow conditions across systems in which the hydrology and geomorphology can vary greatly in both space and time. OHWM delineation in non-perennial (i.e., intermittent and ephemeral) streams can be especially challenging. The U.S. Army Corps of Engineers (USACE) defines intermittent streams as having “flowing water during certain times of the year, when groundwater provides water for stream flow. During dry periods, intermittent streams may not have flowing water. Runoff from rainfall is a supplemental source of water for stream flow” (USACE 2012). Ephemeral streams have “flowing water only during, and for a short duration after, precipitation events in a typical year. Ephemeral stream beds are located above the water table year-round. Groundwater is not a source of water for the stream,” and “[r]unoff from rainfall is the primary source of water for stream flow” (USACE 2012). In contrast to both intermittent and ephemeral streams, perennial streams have “flowing water year-round during a typical year. The water table is located above the stream bed for most of the year,” and “[g]roundwater is the primary source of water for stream flow” (USACE 2012). Given the less persistent streamflow regimes characteristic of non- perennial streams, particularly ephemeral systems, the characterization of ordinary high water flows is perhaps more challenging than in perennially flowing systems. Moreover, depending on climate, vegetation, and other related factors, the appearance of some OHWM indicators may vary greatly between wet and dry seasons or between relatively infrequent flow events, more so than in many perennial streams. Mountainous terrain can present additional challenges to OHWM delineation. For instance, the relatively steep and confined valleys in which mountain streams commonly flow can restrict the development of some alluvial features (e.g., flood-plains, bankfull benches, etc.) that are typical of low-gradient systems and that may help to identify the OHWM. Thus, in non-perennial mountain streams, it is often difficult to determine what constitutes ordinary high water and to interpret the physical and biological indicators established and maintained by ordinary high water flows. Challenges and inconsistencies pertaining to OHWM delineation practices are becoming increasingly relevant in mountainous parts of the western U.S. in light of expanding development. This increased pressure on fluvial systems highlights the need for accurate, consistent, and repeatable OHWM delineation practices in this region. These factors, combined with the particular challenges of OHWM delineation in non-perennial mountain streams, provided the impetus for developing this delineation guide. This guide presents the concepts, field indicators, and methods for assessing, delineating, and documenting the OHWM in non-perennial streams in the Western Mountains, Valleys, and Coast (WMVC) Region of the United States (Figure 1). The information presented here is based on the findings of Mersel et al. (2014) (discussed in Section 1.5) and on years of field observations and data gathering in the WMVC Region and in other regions of the U.S. by the authors and other contributing experts. The remainder of Section 1 provides background information regarding the concept of the OHWM and pertaining to stream hydrology and geomorphology in general. Section 2 discusses and provides examples of the specific field indicators used to identify the OHWM in non-perennial streams in the WMVC Region. Section 3 discusses field methods for delineating the OHWM and addresses additional techniques and lines of evidence that may help in problematic delineation scenarios. The information presented here is technical guidance and does not define, amend, or replace any existing regulations, laws, or legal guidance related to the OHWM or to the regulation of WoUS. Furthermore, determining whether any stream is a jurisdictional WoUS is beyond the scope of this document and involves further assessment in accordance with regulations, case law, and clarifying guidance. This guide pertains to non-perennial streams in the WMVC Region of the U.S., and while the information presented here may have a wider applicability to other regions or to perennial rivers within the WMVC Region, this has not been tested or validated. This manual serves as a companion to A Field Guide to the Identification of the Ordinary High Water Mark (OHWM) in the Arid West Region of the Western United States (Lichvar and McColley 2008) as these two regions—the WMVC and the Arid West—are interspersed with one another. Best professional judgment is required to determine which manual is most appropriate for any given location within these two regions. The technical guidance presented here aims to provide an informed and consistent approach to OHWM delineation within the WMVC Region; however, OHWM delineation is not a precise practice. The OHWM can take on a variety of appearances and characteristics and may change over time due to natural or anthropogenic causes. Best professional judgment and consideration of the unique characteristics of each project site are always required.