McMullin Area Groundwater Sustainability Agency Groundwater Sustainability Plan

McMullin Area Groundwater Sustainability Agency (MAGSA) | November 6th, 2019

McMullin Area Groundwater Sustainability Agency Groundwater Sustainability Plan (Revised)

McMullin Area Groundwater Sustainability Agency (MAGSA) | July 6th, 2022

Measuring and Interpreting Multilayer Aquifer-System Compactions for a Sustainable Groundwater-System Development

American Geophysical Union (AGU) | March 23rd, 2021

Ever decreasing water resources and climate change have driven the increasing use of groundwater causing land subsidence in many countries. Geodetic sensors such as InSAR

Ever decreasing water resources and climate change have driven the increasing use of groundwater causing land subsidence in many countries. Geodetic sensors such as InSAR, GPS and leveling can detect surface deformation but cannot measure subsurface deformation. A single‐well, single‐depth extensometer can be used to measure subsurface deformation, but it cannot delineate the depths of major compaction and provide insight about the deformation mechanism throughout a complex aquifer system, unless man extensometers at different depths are used. We present a multilayer compaction well (MLCW), installed in a borehole, that uses magnetic rings to detect stratum compaction at 25 depths as deep as 300 m below land surface. Our laboratory and field assessments indicate 1 mm precision and accuracy for one single‐depth magnetic reading. We tested the performance of MLCW by measuring aquifer‐system compaction over the proximal, middle, and distal fans of the Choushui River Alluvial Fan (CRAF) that has long experienced severe land subsidence. The MLCW measurements were used to create time‐depth diagrams of compaction, showing different compaction rates at different layers of aquifers and aquitards to identify the depths of major compactions. The elastic (reversible) and inelastic (irreversible) compactions from MLCW were used in stress‐strain analyses to estimate skeletal specific storages and the safe groundwater levels, below which groundwater extractions have caused irreversible compactions. The hydrogeological parameters derived from MLCW measurements can help governmental agencies to determine effective land‐use and water‐use policies, and ascertain the best strategy for utilizing artificial recharge to prevent land subsidence and achieve sustainable groundwater management.

Measuring Land Subsidence from Space

U.S. Geological Survey (USGS) | April 13th, 2000

Interferometric Synthetic Aperture Radar (InSAR) is a powerful new tool that uses radar signals to measure deformation of the Earth’s crust at an unprecedented level of

Interferometric Synthetic Aperture Radar (InSAR) is a powerful new tool that uses radar signals to measure deformation of the Earth’s crust at an unprecedented level of spatial detail and high degree of measurement resolution. InSAR is now being used by the USGS and others to map and monitor subsidence caused by the compaction of aquifer systems. Geophysical applications of radar interferometry take advantage of the phase component of reflected radar signals to measure apparent changes in the range distance of the land surface (Gabriel and others, 1989; Massonnet and Feigl, 1998). Ordinary radar on a typical Earth-orbiting satellite has a very poor ground resolution of about 3 to 4 miles because of the restricted size of the antenna on the satellite. Synthetic Aperture Radar (SAR) takes advantage of the motion of the spacecraft along its orbital track to mathematically reconstruct (synthesize) an operationally larger antenna and yield high-spatial-resolution imaging capability on the order of hundreds of feet.

Measuring What Matters: Setting Measurable Objectives to Achieve Sustainable Groundwater Management in California

Union of Concerned Scientists | September 1st, 2015

Groundwater supplies between 30 and 50 percent of California’s water supply, depending on precipitation, and represents a storage reservoir that is over three times gre

Groundwater supplies between 30 and 50 percent of California’s water supply, depending on precipitation, and represents a storage reservoir that is over three times greater than available surface water storage. The California Water Action Plan (CNRA, CDFA, and CEPA 2014) identifies groundwater as “a critical bu?er to the impacts of prolonged dry periods and climate change on our water system.” Many groundwater basins have historically experienced significant chronic overdraft and related negative impacts. California’s ongoing drought helped spur the state to enact legislation to strengthen local control and management of groundwater basins. Governor Jerry Brown signed the threebill package (AB 1739, SB 1168, SB 1319), known as the Sustainable Groundwater Management Act (SGMA), into law on September 16, 2014. SGMA represents California’s attempt to regulate groundwater comprehensively for the first time in the state’s history. SGMA, which went into e?ect on January 1, 2015, lays out a process and a timeline for local agencies to achieve sustainable management of groundwater basins (see Box 1). It also provides tools, authorities, and deadlines meant to lead to achievement of the legislation’s purpose. For local agencies involved in implementation, the requirements are significant and are expected to take many years to accomplish. While setting measurable objectives is a new requirement, it is by no means a new concept in natural resource management. This report summarizes the theory and practice of setting measurable objectives for groundwater management, using examples from California and elsewhere. The goal is to begin to develop a shared knowledge base and to identify key features of e?ective measurable objectives.

Merced Groundwater Subbasin Groundwater Sustainability Plan

Merced Subbasin Groundwater Sustainability Agency (MSGSA) | November 12th, 2019

Merced Groundwater Subbasin Groundwater Sustainability Plan (Revised)

Merced Subbasin Groundwater Sustainability Agency (MSGSA) | July 6th, 2022

Due to size, this file has been divided into six part. Part 1, Part 2, Part 3, Part 4, Part 5, Part 6

Due to size, this file has been divided into six part. Part 1, Part 2, Part 3, Part 4, Part 5, Part 6

Merced River Watershed Flood-MAR Reconnaissance Study

California Department of Water Resources (DWR) | November 15th, 2023

DWR, in partnership with the Merced Irrigation District (MID), is conducting a preliminary study using flood waters for managed aquifer recharge that can reduce flood ris

DWR, in partnership with the Merced Irrigation District (MID), is conducting a preliminary study using flood waters for managed aquifer recharge that can reduce flood risk, increase surface and groundwater supply reliability, and enhance ecosystems in the Merced River Basin. This Merced River Reconnaissance Study (study) is exploring the potential, feasibility, and effectiveness of Flood-MAR concepts, testing theories, and assessing strategies in overcoming barriers and challenges to project planning and implementation. The study will assess current conditions of the Merced River watershed and the vulnerability of these watershed management characteristics to a range of potential climate change futures. The study will also describe the public and private benefits that may be achieved through Flood-MAR strategies and quantify a range of benefits that Flood-MAR could provide in or adjacent to the Merced River watershed.

Mid-Kaweah Groundwater Sustainability Agency 2022 First Amended Groundwater Sustainability Plan

Mid-Kaweah Groundwater Sustainability Agency (MKGSA) | July 27th, 2022

Due to size, this file has been divided. Part 1, Part 2, Part 3, Part 4, Part 5, Part 6, Part 7, Part 8, Part 9

Due to size, this file has been divided. Part 1, Part 2, Part 3, Part 4, Part 5, Part 6, Part 7, Part 8, Part 9

Mid-Kaweah Groundwater Sustainability Agency Groundwater Sustainability Plan

Mid-Kaweah Groundwater Sustainability Agency (MKGSA) | December 18th, 2019