Lower Mill Creek Watershed Conjunctive Use Project: Tehama County, California

California Department of Water Resources (DWR) | November 18th, 2008

In 1920, the Tehama County Superior Court of the State of California adjudicated entitlements to all Mill Creek flow below 203 cubic feet per second (cfs). As such, water

In 1920, the Tehama County Superior Court of the State of California adjudicated entitlements to all Mill Creek flow below 203 cubic feet per second (cfs). As such, water right holders on Mill Creek legally divert a significant portion of the surface water flow for agricultural beneficial use. During certain times of the year, especially during dry or critically dry years, the agricultural demand for surface water can reduce Mill Creek flow and expose in-stream barriers to fish migration. Fishery experts recognize Mill Creek as a high priority stream for the protection and enhancement of Chinook salmon spawning habitat. Mill Creek surface water diverters currently participate in a long-term cooperative management plan to help provide sufficient flow for fish migration while also maintaining irrigation supplies and the recognition of surface water rights. As part of these efforts, Mill Creek water users participate in water lease and groundwater exchange programs designed to increase in-stream flow during critical spring and fall fish migration periods. Along with other entities, the Department of Water Resources (DWR) plans to establish methods of monitoring and studying fish passage, assessing agricultural water use efficiency, and examining the potential for additional use of groundwater as opposed to use of surface water diversions in the Lower Mill Creek watershed. This report provides a background of the geology and hydrogeology in the Lower Mill Creek watershed area, a detailed discussion of the groundwater resources, and an overview of the potential for conjunctive use of surface water and groundwater resources. It also provides recommendations for additional groundwater monitoring and potentially favorable locations for production well installation associated with possible future conjunctive use programs.

Lower Peninsula Watershed Condition Assessment 2016: Southwest San Francisco Bay, Santa Clara County, San Francisquito to Stevens Creeks. Technical memorandum prepared for the Santa Clara Valley Water District

San Francisco Estuary Institute (SFEI) | October 2nd, 2017

This report describes baseline information about the amount and distribution of aquatic resources, and evaluates that overall ecological conditions of streams using the C

This report describes baseline information about the amount and distribution of aquatic resources, and evaluates that overall ecological conditions of streams using the California Rapid Assessment Method (CRAM), for the Lower Peninsula watershed in Santa Clara County; consisting of Stevens-Permanente Creek, Adobe Creek, southern extent of San Francisquito Creek, and their tributaries. The Lower Peninsula watershed covers approximately 98 square-miles with creeks flowing from the Santa Cruz Mountains into southwest San Francisco Bay and its tidal wetlands.  The Santa Clara Valley Water District’s (District) Safe, Clean Water and Natural Flood Protection Program has many priorities, including Priority D for restoring and protecting vital wildlife habitat, and providing opportunities for increased access to trails and open space. The D5 Project focuses on ecological data collection and analysis at a watershed scale to support the District, other County agencies and organizations in making informed ecological asset management decisions. The key performance indicators (KPIs) for D5 are to:  1. Establish new or track existing ecological levels of service for streams in 5 watersheds.  2. Reassess streams in 5 watersheds to determine if ecological levels of service are maintained or improved. 

Lower Peninsula Watershed Condition Assessment 2016. Technical memorandum prepared for the Santa Clara Valley Water District - Priority D5 Project

San Francisco Estuary Institute (SFEI) | October 2nd, 2017

This report describes baseline information about the amount and distribution of aquatic resources, and evaluates that overall ecological conditions of streams using the C

This report describes baseline information about the amount and distribution of aquatic resources, and evaluates that overall ecological conditions of streams using the California Rapid Assessment Method (CRAM), for the Lower Peninsula watershed in Santa Clara County; consisting of Stevens-Permanente Creek, Adobe Creek, southern extent of San Francisquito Creek, and their tributaries. The Lower Peninsula watershed covers approximately 98 square-miles with creeks flowing from the Santa Cruz Mountains into southwest San Francisco Bay and its tidal wetlands.

Lower Tule River Irrigation District Groundwater Sustainability Agency Groundwater Sustainability Plan

Lower Tule River Irrigation District Groundwater Sustainability Agency | January 21st, 2020

Lower Tule River Irrigation District Groundwater Sustainability Plan San, Joaquin - Tule Subbasin

Lower Tule River Irrigation District Groundwater Sustainability Agency | July 19th, 2023

This Plan addresses the items identified in the SGMA regulations specific to the Agency, including descriptions of the physical characteristics, the water budget (histor

This Plan addresses the items identified in the SGMA regulations specific to the Agency, including descriptions of the physical characteristics, the water budget (historic and future), specific monitoring features and locations, quantifiable targets and minimum thresholds for depth to groundwater, groundwater storage, groundwater quality, and land subsidence between 2020 and 2040, and those projects and management actions proposed to implement during the 20 year planning horizon to achieve the Sustainability Goal.

Machine learning based downscaling of GRACE-estimated groundwater in Central Valley, California

Science of the Total Environment (Elsevier) | January 9th, 2023

California's Central Valley, one of the most agriculturally productive regions, is also one of the most stressed aquifers in the world due to anthropogenic groundwater ov

California's Central Valley, one of the most agriculturally productive regions, is also one of the most stressed aquifers in the world due to anthropogenic groundwater over-extraction primarily for irrigation. Groundwater depletion is further exacerbated by climate-driven droughts. Gravity Recovery and Climate Experiment (GRACE) satellite gravimetry has demonstrated the feasibility of quantifying global groundwater storage changes at uniform monthly sampling, though at a coarse resolution and is thus impractical for effective water resources management. Here, we employ the Random Forest machine learning algorithm to establish empirical relationships between GRACE-derived groundwater storage and in situ groundwater level variations over the Central Valley during 2002–2016 and achieved spatial downscaling of GRACE-observed groundwater storage changes from a few hundred km to 5 km. Validations of our modeled groundwater level with in situ groundwater level indicate excellent Nash-Sutcliffe Efficiency coefficients ranging from 0.94 to 0.97. In addition, the secular components of modeled groundwater show good agreements with those of vertical displacements observed by GPS, and CryoSat-2 radar altimetry measurements and is perfectly consistent with findings from previous studies. Our estimated groundwater loss is about 30 km3 from 2002 to 2016, which also agrees well with previous studies in Central Valley. We find the maximum groundwater storage loss rates of −5.7 ± 1.2 km3 yr−1 and -9.8 ± 1.7 km3 yr−1 occurred during the extended drought periods of January 2007–December 2009, and October 2011–September 2015, respectively while Central Valley also experienced groundwater recharges during prolonged flood episodes. The 5-km resolution Central Valley-wide groundwater storage trends reveal that groundwater depletion occurs mostly in southern San Joaquin Valley collocated with severe land subsidence due to aquifer compaction from excessive groundwater over withdrawal.

Madera Subbasin Joint Groundwater Sustainability Plan

Madera Subbasin Coordination Committee | January 31st, 2022

The Madera Subbasin is identified by California Department of Water Resources (DWR) as a critically overdrafted basin. Therefore, the Madera Subbasin GSAs must develop,

The Madera Subbasin is identified by California Department of Water Resources (DWR) as a critically overdrafted basin. Therefore, the Madera Subbasin GSAs must develop, adopt, and submit a GSP (or GSPs) to DWR for the entire Madera Subbasin by January 31, 2020. The Madera Subbasin is managed by seven GSAs, of which four (City of Madera GSA, Madera Irrigation District GSA, Madera County GSA, and Madera Water District GSA) have developed a joint GSP (attached here) and three (Gravelly Ford Water District GSA, New Stone Water District GSA, and Root Creek Water District GSA) have developed individual GSPs.

Mainstreaming Potable Water Reuse in the United States: Strategies for Leveling the Playing Field

U.S. Environmental Protection Agency (EPA) | April 18th, 2018

The practice of potable water reuse has evolved in important ways in the United States over the past 50 years, especially during the last 25 years. Prior to the 1990s, m

The practice of potable water reuse has evolved in important ways in the United States over the past 50 years, especially during the last 25 years. Prior to the 1990s, many cities and public health regulators recognized that municipal wastewater effluent accounted for a significant fraction of the surface water entering their drinking water treatment plants. Wastewater utilities generally addressed this situation by treating and disinfecting effluent consistent with Clean Water Act permitting requirements and, where feasible, minimizing the fraction of wastewater in drinking water intakes. Because of concerns associated with the presence of wastewater and contaminants from other sources (e.g., industrial pollution, agricultural runoff), some cities began to upgrade drinking water treatment plants by installing advanced treatment technologies to provide enhanced safeguards for public health protection. As water availability and water quality issues became more prevalent in rapidly growing areas, water managers soon began to explicitly consider the use of wastewater effluent to augment water supplies.

Major carbon-14 anomaly in a regional carbonate aquifer—Possible evidence for megascale channeling, south-central Great Basin

American Geophysical Union (AGU) | December 1st, 1976

The carbon 14 content of groundwater at the center of a 16‐km‐long fault‐controlled spring line at Ash Meadows in south central Nevada is 5 times greater than that

The carbon 14 content of groundwater at the center of a 16‐km‐long fault‐controlled spring line at Ash Meadows in south central Nevada is 5 times greater than that in water from other major springs along the lineament. The difference in carbon 14 stands in marked contrast to the near identity of all springwaters in alkalinity, pH, carbon 13, oxygen 18, deuterium, tritium, and other major and trace ions. Ten possible explanations of this major carbon 14 anomaly are evaluated by using all available chemical and isotopic data from basin‐wide wells and upland springs tapping the regional carbonate aquifer discharging at Ash Meadows. The four most plausible hypotheses require the presence of a major longitudinal heterogeneity in the distal portion of the groundwater basin to explain the anomaly. Flow channeling with an amplitude of at least 11 km is indicated. The simplifying assumption commonly used in simulation of basin‐wide flow through fractured or solution‐riddled aquifers, namely, that the aquifer is ‘homogenous in its heterogeneity,’ is not applicable to the dense fractured Paleozoic carbonate rocks comprising the Nevada aquifer; heterogeneities in this aquifer do not cancel each other areally.

Major ground-water flow systems in the Great Basin region of Nevada, Utah, and adjacent state

U.S. Geological Survey (USGS) | July 1st, 1988