California’s Central Valley Groundwater Study: A Powerful New Tool to Assess Water Resources in California’s Central Valley

U.S. Geological Survey (USGS) | June 16th, 2009

Competition for water resources is growing throughout California, particularly in the Central Valley. Since 1980, the Central Valley’s population has nearly

Competition for water resources is growing throughout California, particularly in the Central Valley. Since 1980, the Central Valley’s population has nearly doubled to 3.8 million people. It is expected to increase to 6 million by 2020. Statewide population growth, anticipated reductions in Colorado River water deliveries, drought, and the ecological crisis in the Sacramento–San Joaquin Delta have created an intense demand for water. Tools and information can be used to help manage the Central Valley aquifer system, an important State and national resource. The U.S. Geological Survey (USGS) has released results from a study on the largest water reservoir in the State of California, the Central Valley groundwater system. The findings show continued loss of stored groundwater in the southern part of the valley (see figure below). Since about 1960, groundwater has been depleted by almost 60 million acre-feet, which is, on average, enough to supply every resident of California with water for 8 years. In order to complete the study, the USGS developed an extensive, detailed three-dimensional (3D) computer model of the hydrologic system of the Central Valley (Faunt, 2009). The Central Valley Hydrologic Model (CVHM) simultaneously accounts for changing water supply and demand across the landscape, and simulates surface water and groundwater flow across the entire Central Valley. This new hydrologic modeling tool can be used by water managers to understand how water moves through the aquifer system, predict water-supply scenarios, and address issues related to water competition in California and the Central Valley including: Conjunctive water use (interdependent use of surface water and groundwater); Conservation of agricultural land; Land-use change, including environmental concerns and urbanization, and its effects on water resources; and Effects of climate change.

California’s groundwater overdraft: An environmental Ponzi scheme?

Journal of Hydrology (Elsevier) | January 23rd, 2023

Groundwater levels have been decreasing in most agricultural areas, motivating research to find optimal solutions to balance socio-economical and environmental demands. T

Groundwater levels have been decreasing in most agricultural areas, motivating research to find optimal solutions to balance socio-economical and environmental demands. Traditionally, groundwater optimization aims at long-term profit maximization, while accounting for the extraction costs. Following this approach, we find exploitation protocols characterized by pumping rates that slowly decrease in time toward a long-term sustainable value. However, the comparison of the model prediction with water extraction data for the period 1985–2021 from Kern County in California points out the inconsistencies between real management and long-term optimal behavior. Rather, the observed trajectory resembles those obtained by finite-time optimization horizons, which provide short-term high profits by over-drafting, while leading to long-term dilapidation of the capital and the exhaustion of the aquifer. Such myopic planning results in a Ponzi scheme for groundwater extraction. Like the infamous fraudulent scheme, ‘more-than-optimal’ profits are achievable by excessive short-term consumption by the early investors (the past and current aquifer exploiters), leaving the later comers (the future generations) with an impossible cost to sustain. Including the environmental costs of aquifer over-exploitation, the myopic nature of human planning can be corrected and reconciled with a more sustainable use of groundwater.

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

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 Flood Protection Plan (2012)

California Department of Water Resources (DWR) | June 12th, 2012

The Central Valley Flood Protection Plan (CVFPP) is a critical document to guide California’s participation (and influence federal and local participation) in managing

The Central Valley Flood Protection Plan (CVFPP) is a critical document to guide California’s participation (and influence federal and local participation) in managing flood risk along the Sacramento River and San Joaquin River systems. The CVFPP proposes a system-wide investment approach for sustainable, integrated flood management in areas currently protected by facilities of the State Plan of Flood Control (SPFC). The CVFPP will be updated every five years, with each update providing support for subsequent policy, program, and project implementation. The State of California (State) conducted planning and investigations for the 2012 CVFPP from 2009 through 2011, representing the most comprehensive flood evaluations for the Central Valley. Following the anticipated adoption of the CVFPP in 2012 by the Central Valley Flood Protection Board (Board), preparation of regional- and State-level financing plans will guide investments in the range of $14 billion to $17 billion during the next 20 to 25 years.  These financing plans are critical to CVFPP implementation, given the uncertainty in State, federal, and local agency budgets and cost-sharing capabilities.

Central Valley Flood Protection Plan 2022 (draft)

California Department of Water Resources (DWR) | April 21st, 2022

The Central Valley Flood Protection Plan (CVFPP) describes a programmatic vision for improving flood risk management throughout the Central Valley. Prepared by the Calif

The Central Valley Flood Protection Plan (CVFPP) describes a programmatic vision for improving flood risk management throughout the Central Valley. Prepared by the California Department of Water Resources (DWR) in accordance with the Central Valley Flood Protection Act of 2008 (Act) and adopted by the Central Valley Flood Protection Board (CVFPB) in June 2012, the CVFPP guides the State’s participation in managing flood risk in areas protected by the State Plan of Flood Control (SPFC). The Public Draft 2022 CVFPP Update is the second update required every five years by the Act. The CVFPP recommends actions and policies informed by engagement with stakeholders and partners and prioritizes investments over a 30-year horizon. Click here for the comment form, supporting documents, and DWR links.

Central Valley Flood Protection Plan Appendix K. Synthesis of Fish Migration Improvement Opportunities in the Central Valley Flood System

California Department of Water Resources (DWR) | July 14th, 2016

Many instream structures in the Central Valley adversely affect native anadromous fish migration. These structures, often referred to as fish passage barriers, reduce or

Many instream structures in the Central Valley adversely affect native anadromous fish migration. These structures, often referred to as fish passage barriers, reduce or eliminate longitudinal habitat connectivity; prevent or limit access to critical spawning, rearing, and refuge habitat; create migration delays; and create lethal or sublethal conditions for native anadromous species (California Department of Water Resources [DWR] 2012a, 2014; National Marine Fisheries Service [NMFS] 2014). Fish passage barriers associated with the Central Valley flood system trigger compliance requirements under the federal and California Endangered Species Acts; necessitate recurring fish rescues; and impel additional permitting requirements, such as long-term mitigation (NMFS 2009; Vogel 2011; DWR 2012b; Johnson and Vincik 2012; Cannon 2013; Heise 2013; Hendrick and Swart 2013).  Identification of migration impediments and associated improvement opportunities in the flood system is needed for integrated flood management planning. Fish migration improvements can be integrated into flood risk reduction projects1 to yield cost efficiencies in the project planning and implementation phases, and they may result in long-term economic and environmental benefits (DWR 2014). Two documents, the Fish Passage Assessment (Attachment 9C of the Central Valley Flood Protection Plan [CVFPP]) and the Draft Central Valley Flood System Fish Migration Improvement Opportunities (FMIO) report have been prepared to assist in identifying and prioritizing fish migration improvement opportunities in the flood system. 

Central Valley Flood Protection Plan Conservation Strategy 2022 Update

California Department of Water Resources (DWR) | November 4th, 2022

The Central Valley Flood Protection Plan (CVFPP) Conservation Strategy (Conservation Strategy or Strategy) is a primary component of the CVFPP in accordance with the Cent

The Central Valley Flood Protection Plan (CVFPP) Conservation Strategy (Conservation Strategy or Strategy) is a primary component of the CVFPP in accordance with the Central Valley Flood Protection Act of 2008. It aligns with and contributes to the attainment of all CVFPP goals, while focusing on improving ecosystem quality, quantity, function, and sustainability within the Systemwide Planning Area (SPA). Its purpose is to provide actionable and measurable targets to improve riverine, aquatic, wetland, and riparian habitat in the flood system through the integration of ecological principles with flood risk reduction projects, operation and maintenance activities, institutional support, and other means (e.g., the remediation of fish passage barriers). The Conservation Strategy also provides data, information, and guidance to floodplain managers to assist in the development of multi-benefit flood infrastructure improvement projects by integrating project components and management strategies that benefit native species and their habitats.

Central Valley Flood Protection Plan Update 2017

California Department of Water Resources (DWR) | August 29th, 2017

The Central Valley Flood Protection Plan (CVFPP) has guided the State’s participation in managing flood risk in areas protected by the State Plan of Flood Control (SPFC

The Central Valley Flood Protection Plan (CVFPP) has guided the State’s participation in managing flood risk in areas protected by the State Plan of Flood Control (SPFC) since the plan’s adoption pursuant to the Central Valley Flood Protection Act of 2008 in 2012. A strategic, long-range plan, the CVFPP and its updates describe a programmatic vision for flood system improvements over time in accordance with the requirements of the 2008 Act. The CVFPP was prepared by the Department of Water Resources (DWR) and adopted by Central Valley Flood Protection Board (CVFPB) through Resolution 2012-25. As conceived by the legislature, the CVFPP is updated every 5 years, beginning in 2017.