Castac Lake Valley Groundwater Sustainability Plan

Castac Basin Groundwater Sustainability Agency | September 17th, 2020

The Castac Lake Valley Groundwater Basin (also referred to herein as “the Basin”), California Department of Water Resources (DWR) Basin No. 5-029, is located at the

The Castac Lake Valley Groundwater Basin (also referred to herein as “the Basin”), California Department of Water Resources (DWR) Basin No. 5-029, is located at the southern end of Kern County. The Basin is identified by DWR as being a very low priority basin, and as such, this GSP and associated SGMA compliance efforts have been conducted on a voluntary basis. Due to size, the file has been divided into two parts. Part 1, Part 2

Center for Biological Diversity vs. Lincoln County Water District

Nevada Appellate Courts | January 25th, 2024

This case examines whether the State Engineer has the authority to redesignate multiple existing hydrographic basins as one "superbasin" based on a shared source of water

This case examines whether the State Engineer has the authority to redesignate multiple existing hydrographic basins as one "superbasin" based on a shared source of water for purposes of the water's administration and management. We also look at whether the State Engineer complied with due process in creating the superbasin at issue here.

Central and West Basin Water Replenishment District, etc. v. Charles E. Adams, et al

Superior Court of California, County of Los Angeles | December 23rd, 2013

Note from “An Evaluation of California’s Adjudicated Groundwater Basins” by Langridge et al: "Third Amendment Judgment to the Central Basin adjudication ... allo

Note from “An Evaluation of California’s Adjudicated Groundwater Basins” by Langridge et al: "Third Amendment Judgment to the Central Basin adjudication ... allowed parties holding water rights to store water in the Central Basin for later recovery; DWR was replaced with a new Watermaster consisting of three separate arms with different functions: Administrative Body, Water Rights Panel, and a Storage Panel."

Central Coast Groundwater: Seawater Intrusion and Other Issues

California Water Foundation | August 4th, 2014

The Central Coast area relies on groundwater for more than 80 percent of its water supplies, a greater percentage than any other region in the state. Over 40 percent of t

The Central Coast area relies on groundwater for more than 80 percent of its water supplies, a greater percentage than any other region in the state. Over 40 percent of the groundwater basins in the Central Coast region were ranked as either “high” or “medium” priority as part of the California Statewide Groundwater Elevation Monitoring (CASGEM) prioritization released in June 2014, indicating that they are among the most threated by present or future increases in groundwater demand. Central Coast groundwater supplies are seriously threatened by over-pumping that causes seawater intrusion, a challenge unique to coastal communities. Seawater intrusion results in saline groundwater that is unsuitable for irrigation or domestic use, directly threatening the Central Coast’s economy, where many high-value, salt-sensitive crops, such as strawberries, are grown. Groundwater basins in the Monterey and Salinas Valley area are in a state of long-term overdraft, resulting in falling groundwater levels, regional seawater intrusion, and reduced groundwater storage. Seawater intrusion reaches more than five miles inland in the Salinas Valley and three miles inland in the Pajaro Valley. In addition to salinity issues, several groundwater contaminants are present in these aquifers, including elevated levels of total dissolved solids, iron, manganese, nitrates, and other trace elements. The Paso Robles groundwater subbasin supplies water for 29 percent of the population and an estimated 40 percent of the agricultural production of San Luis Obispo County. Groundwater levels in the basin have been dropping rapidly in recent years, with many areas experiencing groundwater level declines of more than 70 feet. As a result, many wells have gone dry and groundwater users have been forced to deepen their wells or drill new wells. In July 2013, over 100 rural property owners complained to the San Luis Obispo County Board of Supervisors that their wells were running dry and in August 2013 the Board adopted the “Paso Robles Groundwater Basin Urgency Ordinance” as a temporary action to prevent new pumping from worsening overdraft conditions. Additionally, land surface subsidence has been noted in the Paso Robles area, and the recent rapid groundwater level declines may have triggered additional subsidence in this area. Although groundwater levels in the Oxnard Plain area have been relatively stable or have shown an increasing trend, in the coastal regions this stability is largely due to seawater intrusion and results in water of unusable quality replacing high quality groundwater. Rising groundwater levels in the Las Posas Valley are a result of active management to increase groundwater recharge beneath the Arroyo Las Posas. Seawater intrusion began in the Oxnard Plain area by 1930s and was widespread as early as the 1940s. Changes in groundwater management, including pumping reductions, shifting of pumping locations, construction of the Freeman Diversion, and the operation of the Pumping Trough and Pleasant Valley pipeline systems have significantly reduced seawater intrusion, but seawater intrusion conditions persist. Other contaminants present in the region include nitrates, iron, manganese and sulfate. In addition to causing seawater intrusion, over-pumping also caused irreversible land subsidence ranging from 2 .5 to 5 feet in several areas of the basin. The Central Coast is critically dependent upon groundwater, but this resource is under serious threat in a number of basins. In light of the limitations of existing state policies, the following measures would improve the effectiveness of groundwater planning and support sustainable management of California’s Central Coast’s groundwater resources . Establish a statewide policy to manage groundwater sustainably. Organize and empower local groundwater agencies to manage groundwater subbasins. Require the development and implementation of groundwater sustainability plans by local groundwater agencies. Provide local agencies with technical guidance and financial support from the state. Empower the State to oversee and ensure the implementation of groundwater sustainability plans.

Central Coast Hydrologic Region Groundwater Update

California Department of Water Resources (DWR) | April 1st, 2015

The primary goal of the Central Coast Hydrologic Region (Central Coast region) groundwater update is to expand information about region-specific groundwater conditions fo

The primary goal of the Central Coast Hydrologic Region (Central Coast region) groundwater update is to expand information about region-specific groundwater conditions for California Water Plan Update 2013, and to guide more informed groundwater management actions and policies. A second goal is to steadily improve the quality of groundwater information in future California Water Plan (CWP) updates to a level that will enable regional water management groups (RWMGs) to accurately evaluate their groundwater resources and implement management strategies that can meet local and regional water resource objectives within the context of broader statewide objectives. The final goal is to identify data gaps and groundwater management challenges meant to serve as a guidepost for prioritizing future data collection and funding opportunities relevant to the region. This regional groundwater update is not intended to provide a comprehensive and detailed examination of local groundwater conditions, or be a substitute for local studies and analysis.  Consequently, where information is readily available, the update does report some aspects of the regional groundwater conditions in greater detail.

Central Kings Groundwater Sustainability Agency Groundwater Sustainability Plan

Central Kings Groundwater Sustainability Agency (CKGSA) | December 11th, 2019

Central Kings Groundwater Sustainability Agency Groundwater Sustainability Plan (Revised)

Central Kings Groundwater Sustainability Agency (CKGSA) | July 13th, 2022

Central Valley Region Salt and Nitrate Management Plan

Central Valley Salinity Alternatives for Long-Term Sustainability (CV-SALTS) | January 19th, 2017

Elevated salinity and nitrates in surface water and groundwater are increasing problems affecting much of California, other western states, and arid regions throughout th

Elevated salinity and nitrates in surface water and groundwater are increasing problems affecting much of California, other western states, and arid regions throughout the world. In California, as surface and groundwater supplies become scarcer, and as wastewater streams become more concentrated, salinity and nitrate impairments are occurring with greater frequency and magnitude. In 2006, the Central Valley Water Board, the State Water Board, and stakeholders began a joint effort to address salinity and nitrate problems in California’s Central Valley and adopt long-term solutions that will lead to enhanced water quality and economic sustainability. Central Valley Salinity Alternatives for Long-Term Sustainability (CV-SALTS) is a collaborative basin planning effort aimed at developing and implementing a comprehensive salinity and nitrate management program. The goal of CV-SALTS is to maintain a healthy environment and a good quality of life for all Californians by protecting our most essential and vulnerable resource: WATER. In July 2008, the Central Valley Salinity Coalition (CVSC) was formed.  CVSC represents stakeholder groups working with the Board in the CV-SALTS effort.  Its purpose is to organize, facilitate and fund efforts needed to fulfill the goals of CV-SALTS.  CVSC coordinates the meetings of the CV-SALTS committees, maintains an independent web site, and manages the projects originating from this effort.  Information and materials regarding the stakeholder committees and other activity, including the meeting schedule, are posted on their website: www.cvsalinity.org. The Final SNMP for Central Valley Water Board Consideration was completed in December 2016. The Central Valley Water Board staff plans to release this version of the SNMP and all of its supporting attachments in January 2017 for a comment period so that the public has the opportunity to review the SNMP documentation before a general information workshop is held with the Central Valley Water Board, currently planned for March 2017.

Changing the course? What's worked, what hasn't and what's next for the SCWP: An assessment of the first three rounds of the Safe Clean Water Program

Los Angeles Waterkeeper (LA Waterkeeper) | February 16th, 2023

In 2018, Los Angeles County voters overwhelmingly approved “Measure W” — a 2.5 cent per square foot parcel tax on impervious surface on all land parcels within the

In 2018, Los Angeles County voters overwhelmingly approved “Measure W” — a 2.5 cent per square foot parcel tax on impervious surface on all land parcels within the LA County Flood Control District to fund multi-benefit stormwater infrastructure. The Safe Clean Water Program (SCWP) was developed to distribute and manage the funds raised, approximately $280M annually. The SCWP operates through three distinct programs: the District Program (10% of funds), the Municipal Program (40% of funds), and the Regional Program (50% of funds). The Regional Program has recently completed its third round of funding awarded through a competitive grant process. This assessment focuses on how the Regional Program is performing in achieving the SCWP’s overarching goals of water quality, water supply, and community investment benefits as provided in the ordinance authorizing this measure for the ballot. It also explores how well the program is meeting its goals around community engagement and support, benefits to disadvantaged communities, and green workforce development. The purpose of this assessment is to help the SCWP’s Regional Oversight Committee (ROC) and ultimately other decision-makers such as the LA County Board of Supervisors better understand what is working well with the program and where improvements could be made as part of the biennial review.

Chapter A of Natural and Anthropogenic (Human-Made) Hexavalent Chromium, Cr(VI), in Groundwater near a Mapped Plume, Hinkley, California: Introduction to Study Area Hydrogeology, Chromium Sources, Site History, and Purpose of Study

U.S. Geological Survey (USGS) | April 25th, 2023

Documents in this series: Chapter A: Introduction to Study Area Hydrogeology, Chromium Sources, Site History, and Purpose of Study Chapter B: Survey of Chromium and

Documents in this series: Chapter A: Introduction to Study Area Hydrogeology, Chromium Sources, Site History, and Purpose of Study Chapter B: Survey of Chromium and Selected Element Concentrations in Rock, Alluvium, and Core Material Chapter C: Chromium in Minerals and Selected Aquifer Materials Chapter D: Analyses of Regulatory Water-Quality Data Chapter E: Groundwater Chemistry and Hexavalent Chromium Chapter F: Environmental Tracers of Groundwater Source, Age, and Geochemical Evolution Chapter G: Evaluation of Natural and Anthropogenic (Human-Made) Hexavalent Chromium Chapter H: Predevelopment Water Levels, Groundwater Recharge, and Selected Hydrologic Properties of Aquifer Materials, Hinkley and Water Valleys, California Chapter I: Sequestration and Reoxidation of Chromium in Experimental Microcosms Chapter J: Summary and Conclusions Between 1952 and 1964, hexavalent chromium, Cr(VI), was released into groundwater from the Pacific Gas and Electric Company (PG&E) Hinkley compressor station in the Mojave Desert 80 miles (mi) northeast of Los Angeles, California. Remediation began in 1992, and in 2010, site cleanup was projected to require between 10 and 95 years and was expected to cost between $36 and $176 million. A 2007 PG&E study estimated the natural Cr(VI) background in groundwater in Hinkley Valley to be 3.1 micrograms per liter (μg/L). This concentration was used for interim regulatory purposes by the Lahontan Regional Water Quality Control Board (RWQCB). In the fourth quarter (October–December) 2015, the regulatory Cr(VI) plume extended about 3.0 mi downgradient from the release location within the Hinkley compressor station, while groundwater having Cr(VI) concentrations greater than 3.1 μg/L was present more than 8 mi downgradient. Although rocks and minerals in the area are naturally low in chromium, alluvium eroded from the San Gabriel Mountains and transported to Hinkley Valley by the Mojave River, and locally small exposures of mafic rock, including hornblende diorite and basalt, may contribute Cr(VI) to groundwater. In response to limitations of the PG&E 2007 Cr(VI) background study’s methodology, uncertainty in the natural Cr(VI) background concentration, and an increase in the mapped extent of groundwater having Cr(VI) concentrations greater than the interim regulatory background of 3.1 μg/L, the Lahontan RWQCB concluded that the 2007 PG&E background Cr(VI) study should be updated. The purpose of the updated study is to estimate background Cr(VI) concentrations in groundwater within the upper aquifer upgradient, downgradient, near the margins, and within the footprint of the PG&E Cr(VI) plume in Hinkley, California. The scope of the study included eight tasks; results from those tasks are presented in the chapters within this professional paper.