Nitrate Implementation Measures Study (NIMS) Final Report

Central Valley Salinity Alternatives for Long-Term Sustainability (CV-SALTS) | March 31st, 2016

This report summarizes the Nitrate Implementation Measures Study (NIMS) which addresses nitrate contamination in the groundwater basins underlying the floor of the Centra

This report summarizes the Nitrate Implementation Measures Study (NIMS) which addresses nitrate contamination in the groundwater basins underlying the floor of the Central Valley and appropriate implementation measures to mitigate nitrate contamination for these areas using a phased approach that includes providing safe drinking water, reducing or eliminating impacts to drinking water sources and implementing managed restoration activities where needed to restore beneficial uses in groundwater. These implementation measures will be incorporated into the SNMP. The findings from both the SSALTS and the NIMS will be used to guide discussions regarding the need for changes to the existing Basin Plan to facilitate salt disposal and mitigation measures for nitrate in a manner that is most beneficial to the region covered by the SNMP. 

Nitrogen Fertilizer Loading to Groundwater in the Central Valley

University of California, Davis (UC Davis) | October 31st, 2017

Nitrate‐nitrogen is the most common pollutant found in the Central Valley aquifer system of California. This project provides a long‐term assessment of past and curr

Nitrate‐nitrogen is the most common pollutant found in the Central Valley aquifer system of California. This project provides a long‐term assessment of past and current potential nitrogen loading to groundwater on irrigated and natural lands across the entire Central Valley of California using a nitrogen mass balance approach; assesses the long‐term implications for groundwater quality in the Central Valley (Sacramento Valley, San Joaquin Valley, and Tulare Lake Basin); evaluates potential best management practices to reduce groundwater nitrogen loading from irrigated lands; and provides a planning tool to better understand local and regional groundwater quality response to specific best management practices and policy/regulatory actions. The project complements other work to assess the vulnerability of Central Valley groundwater to nitrate contamination, sources of nitrate in groundwater, and how to reduce source loading.

North Fork Kings Groundwater Sustainability Agency Groundwater Sustainability Plan (Revised)

North Fork Kings Groundwater Sustainability Agency (NFKGSA) | July 14th, 2022

North Fork Kings Groundwater Sustainability Plan

North Fork Kings Groundwater Sustainability Agency (NFKGSA) | December 18th, 2019

North Kings Groundwater Sustainability Groundwater Sustainability Plan

North Kings Groundwater Sustainability Agency | November 21st, 2019

Northern and Central Delta-Mendota Regions Revised Groundwater Sustainability Plan

San Luis & Delta-Mendota Water Authority (SLDMWA) | June 24th, 2022

Within the Delta-Mendota Subbasin, six (6) GSPs have been developed in a coordinated fashion with the goal of achieving sustainability for the Subbasin as a whole. The GS

Within the Delta-Mendota Subbasin, six (6) GSPs have been developed in a coordinated fashion with the goal of achieving sustainability for the Subbasin as a whole. The GSP Groups preparing the coordinated GSPs include: the Aliso Water District GSP Group, Farmers Water District GSP Group, Fresno County GSP Group, Grassland GSP Group, Northern & Central Delta-Mendota Region GSP Group, and San Joaquin River Exchange Contractors GSP Group. This GSP has been developed for the Northern and Central Delta-Mendota Regions, which are comprised of the following eight Groundwater Sustainability Agencies (GSAs): Central Delta-Mendota, City of Patterson, DM-II, Northwestern Delta-Mendota, Oro Loma Water District, Patterson Irrigation District, West Stanislaus Irrigation District, and Widren Water District. The Northern & Central Delta-Mendota Region GSP has been developed by these GSAs to meet SGMA regulatory requirements while reflecting local needs and preserving local control over water resources. This GSP provides a path to achieve and document sustainable groundwater management within 20 years following adoption, promoting the long-term sustainability of locally-managed groundwater resources now and into the future. Due to size, this file has been divided. Part 1, Part 2, Part 3

Notice of Entry of Order for Implementation of Preliminary Injunction – Case No. Bcv-22-103220-Gap, Bring Back the Kern et al v. City of Bakersfield et al

Superior Court of California, County of Kern | November 14th, 2023

Occurrence and sources of radium in groundwater associated with oil fields in the southern San Joaquin Valley, California

American Chemical Society (ACS) | August 7th, 2019

Geochemical data from 40 water wells were used to examine the occurrence and sources of radium (Ra) in groundwater associated with three oil fields in California (Fruitva

Geochemical data from 40 water wells were used to examine the occurrence and sources of radium (Ra) in groundwater associated with three oil fields in California (Fruitvale, Lost Hills, South Belridge). 226Ra+228Ra activities (range = 0.010–0.51 Bq/L) exceeded the 0.185 Bq/L drinking-water standard in 18% of the wells (not drinking-water wells). Radium activities were correlated with TDS concentrations (p < 0.001, ρ = 0.90, range = 145–15,900 mg/L), Mn + Fe concentrations (p < 0.001, ρ = 0.82, range = <0.005–18.5 mg/L), and pH (p < 0.001, ρ = −0.67, range = 6.2–9.2), indicating Ra in groundwater was influenced by salinity, redox, and pH. Ra-rich groundwater was mixed with up to 45% oil-field water at some locations, primarily infiltrating through unlined disposal ponds, based on Cl, Li, noble-gas, and other data. Yet 228Ra/226Ra ratios in pond-impacted groundwater (median = 3.1) differed from those in oil-field water (median = 0.51). PHREEQC mixing calculations and spatial geochemical variations suggest that the Ra in the oil-field water was removed by coprecipitation with secondary barite and adsorption on Mn–Fe precipitates in the near-pond environment. The saline, organic-rich oil-field water subsequently mobilized Ra from downgradient aquifer sediments via Ra-desorption and Mn/Fe-reduction processes. This study demonstrates that infiltration of oil-field water may leach Ra into groundwater by changing salinity and redox conditions in the subsurface rather than by mixing with a high-Ra source.

On-farm flood capture could reduce groundwater overdraft in Kings River Basin

California Agriculture (UCANR) | November 16th, 2016

Chronic groundwater overdraft threatens agricultural sustainability in California’s Central Valley. Diverting flood flows onto farmland for groundwater rechar

Chronic groundwater overdraft threatens agricultural sustainability in California’s Central Valley. Diverting flood flows onto farmland for groundwater recharge offers an opportunity to help address this challenge. We studied the infiltration rate of floodwater diverted from the Kings River at a turnout upstream of the James Weir onto adjoining cropland; and calculated how much land would be necessary to capture the available floodwater, how much recharge of groundwater might be achieved, and the costs. The 1,000-acre pilot study included fields growing tomatoes, wine grapes, alfalfa and pistachios. Flood flows diverted onto vineyards infiltrated at an average rate of 2.5 inches per day under sustained flooding. At that relatively high infiltration rate, 10 acres are needed to capture one CFS of diverted flood flow. We considered these findings in the context of regional expansion. Based upon a 30-year record of Kings Basin surplus flood flows, we estimate 30,000 acres operated for on-farm flood recharge would have had the capacity to capture 80% of available flood flows and potentially offset overdraft rates in the Kings Basin. Costs of on-farm flood capture for this study were estimated at $36 per acre-foot, less than the cost for surface water storage and dedicated recharge basins.

Outmigration survival of wild Chinook salmon smolts through the Sacramento River during historic drought and high water conditions

Environmental Biology of Fishes (Springer) | January 27th, 2020