Elsinore Valley Subbasin Groundwater Sustainability Plan

Elsinore Valley Municipal Water District | December 23rd, 2021

The Elsinore Valley Subbasin is located within the service area of Elsinore Valley Municipal Water District (EVMWD or District). No other agencies overlap the boundaries

The Elsinore Valley Subbasin is located within the service area of Elsinore Valley Municipal Water District (EVMWD or District). No other agencies overlap the boundaries of this subbasin therefore no inter-agency coordination was required for the development of this GSP. Two outside technical experts participated as the technical advisory committee for the GSP development. EVMWD conducted public outreach throughout the development of the GSP.

Emergency Drought Barriers

Delta Stewardship Council (Delta Council) | April 26th, 2022

Emergency Measures to Provde Water Resources in California and Improve Disaster Response in Certain Areas

The White House | January 24th, 2025

Emergency Response To Flood Threats in California

California Department of Water Resources (DWR) | April 8th, 2011

An explanatory memo on the Flood Operations Branch, Department of Water Resources, Division of Flood Management During the flood season, a number of public agencies co

An explanatory memo on the Flood Operations Branch, Department of Water Resources, Division of Flood Management During the flood season, a number of public agencies combine their efforts to provide high water warnings and minimize flood damage in California. The Department of Water Resources (DWR) is responsible for coordinating local, State and federal flood operations. The State-Federal Flood Operations Center, located on El Camino Avenue in Sacramento, is the focal point of this effort. State, federal and local flood operations on the North Coast streams are coordinated through the DWR Eureka Flood Center in Humboldt County.

Emergent Trends Complicate the Interpretation of the United States Drought Monitor (USDM)

American Geophysical Union (AGU) | April 25th, 2024

Effective drought management must be informed by an understanding of whether and how current drought monitoring and assessment practices represent underlying nonstationar

Effective drought management must be informed by an understanding of whether and how current drought monitoring and assessment practices represent underlying nonstationary climate conditions, either naturally occurring or forced by climate change. Here we investigate the emerging climatology and associated trends in drought classes defined by the United States Drought Monitor (USDM), a weekly product that, since 2000, has been used to inform drought management in the United States. The USDM classifies drought intensity based in part on threshold percentiles in key hydroclimate quantities. Here we assess how those USDM‐defined drought threshold percentiles have changed over the last 23 years, examining precipitation, runoff, soil moisture (SM), terrestrial water storage (TWS), vapor pressure deficit (VPD), and near‐surface air temperature. We also assess underlying trends in the frequency of drought classifications across the U.S. Our analysis suggests that the frequency of drought class occurrence is exceeding the threshold percentiles defined by the USDM in a number of regions in the United States, particularly in the American West, where the last 23 years have emerged as a prolonged dry period. These trends are also reflected in percentile‐based thresholds in precipitation, runoff, SM, TWS, VPD, and temperature. Our results emphasize that while the USDM appears to be accurately reflecting observed nonstationarity in the physical climate, such trends raise critical questions about whether and how drought diagnosis, classification, and monitoring should address long‐term intervals of wet and dry periods or trends

Emerging PFAS Trends in Water and Sediment from San Francisco Bay

San Francisco Estuary Institute (SFEI) | August 14th, 2025

Per- and polyfluoroalkyl substances (PFAS) are a diverse class of persistent compounds, including several that are bioaccumulative and known or suspected to be toxic. The

Per- and polyfluoroalkyl substances (PFAS) are a diverse class of persistent compounds, including several that are bioaccumulative and known or suspected to be toxic. These unique compounds have widespread uses across consumer, commercial, and industrial products, resulting in widespread occurrence in humans, the environment, and wildlife across the globe. Within San Francisco Bay, the RMP has monitored PFAS across the Bay ecosystem, beginning in 2004 with various biota and since expanding to sediment, surface water, stormwater, and wastewater. These studies found PFAS throughout the Bay, especially in sport fish, where concentrations are of potential concern for human health and led to a classification of PFAS as High Concern for the Bay under the RMP tiered risk-based framework for emerging contaminants.  This study examined Bay sediment and surface water to continue to build our understanding of the occurrence, fate, and risks of PFAS to ecological and human health. Using a targeted method, 40 PFAS were analyzed in Bay sediment collected in three monitoring cruises from 2017 to 2023, and Bay water collected from 2021 to 2023 during both the dry and wet seasons. The Total Oxidizable Precursor (TOP) assay was also used to supplement these findings by indirectly measuring unknown perfluoroalkyl acid (PFAA) precursors of detectable PFAS. This additional information aids in elucidating the broader levels of PFAS present in samples to better evaluate the exposure and risk to the Bay. 

Emerging trends in global freshwater availability

Nature Portfolio (Springer Nature) | May 17th, 2018

Freshwater availability is changing worldwide. Here we quantify 34 trends in terrestrial water storage observed by the Gravity Recovery and Climate Experiment (GRACE) sat

Freshwater availability is changing worldwide. Here we quantify 34 trends in terrestrial water storage observed by the Gravity Recovery and Climate Experiment (GRACE) satellites during 2002–2016 and categorize their drivers as natural interannual variability, unsustainable groundwater consumption, climate change or combinations thereof. Several of these trends had been lacking thorough investigation and attribution, including massive changes in northwestern China and the Okavango Delta. Others are consistent with climate model predictions. This observation-based assessment of how the world’s water landscape is responding to human impacts and climate variations provides a blueprint for evaluating and predicting emerging threats to water and food security.

Emerging understanding of the potential role of seagrass and kelp as an ocean acidification management tool in California

California Ocean Science Trust (OST) | January 2nd, 2018

This report was produced by the OPC-SAT working group and Ocean Science Trust on behalf of the Ocean Protection Council (OPC) and the broader community of California man

This report was produced by the OPC-SAT working group and Ocean Science Trust on behalf of the Ocean Protection Council (OPC) and the broader community of California managers with the aim of: • communicating emerging scientific understanding of the ability of seagrass and macroalgae (kelps) to ameliorate ocean acidification (OA) in a California-specific context, • summarizing knowledge gaps and opportunities for filling them through research and monitoring, and • providing guidance on next steps for the State as it considers future nature-based actions to reduce the negative impacts of OA in California and beyond.

Empirical and Experimental Analyses of Secondary Louver Efficiency at the Tracy Fish Collection Facility: March 1996 to November 1997

U.S. Bureau of Reclamation (USBR) | January 30th, 2004

Empirical Models of Shallow Groundwater and Multi-Hazard Flood Forecasts as Sea-Levels Rise

American Geophysical Union (AGU) | February 8th, 2025

Knowledge of coastal hydrogeology and hazards as groundwater responds to sea-level rise (SLR) can be improved through installation of shallow groundwater monitoring piezo

Knowledge of coastal hydrogeology and hazards as groundwater responds to sea-level rise (SLR) can be improved through installation of shallow groundwater monitoring piezometers and continuous observations. Interpolation of site data enables mapping of the present-day state of groundwater elevation, depth to groundwater (DTW), their temporal statistical variation, and differing spatial responses to tides and rainfall. Future DTW and its variability can be projected under increments of SLR, with assumptions and caveats, to show where and when episodic and/or permanent inundation can be expected. This methodology is outlined in a case study of Dunedin, New Zealand, which enabled comparison of rising groundwater's contribution to pluvial flooding and groundwater emergence with coastal inundation. Changes in relative land exposure with SLR shows evolution in flood hazard from current pluvial-dominated events, into “flooding from below” and groundwater emergence, in advance of any overland coastal inundation. Dunedin exemplifies how groundwater transfers effects of SLR surprisingly far inland, but the lowest-lying or shoreline-proximal suburbs are not necessarily the most vulnerable. Unlike coastal inundation, rising groundwater is unconstrained by protective topography and presents as a creeping hazard, or contributor to hazards such as pluvial flooding, which can be widespread, occurring already and difficult to defend against. The empirical models contain assumptions and uncertainties important to the veracity of results and application. While conservative (“risk averse”) and a compromise from computationally expensive numerical solutions, their value is in providing the spatial and temporal precision needed for multi-source hazard assessment and holistic adaptive planning.