Spectral characterization of dissolved organic matter in groundwater to assess mixing with oil-field water near selected oil fields, southern California

Science of The Total Environment (Elsevier) | September 16th, 2023

Spring 2017 Groundwater Level Data Summary

California Department of Water Resources (DWR) | October 3rd, 2022

This document presents a summary of fall 2017 groundwater level data available in the DWR groundwater level database as of February 21, 2018 and includes a discussion of

This document presents a summary of fall 2017 groundwater level data available in the DWR groundwater level database as of February 21, 2018 and includes a discussion of fall 2017, data coverage and groundwater level trends. Statewide precipitation data come from the U.S. Climate Divisional Database, which has data from January 1895 to the present.

SSALTS Final Phase 3 Report: Evaluate Potential Salt Disposal Alternatives to Identify Acceptable Alternatives for Implementation

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

The purpose of the Strategic Salt Accumulation Land and Transportation Study (SSALTS) is to identify the range of viable Central Valley alternatives for salt disposal to

The purpose of the Strategic Salt Accumulation Land and Transportation Study (SSALTS) is to identify the range of viable Central Valley alternatives for salt disposal to provide input for consideration during development of the Salt and Nitrate Management Plan (SNMP) for the region under the jurisdiction of the Central Valley Regional Water Quality Control Board (Central Valley Water Board). The findings have been used to guide discussions regarding establishment of regional salt management policies and the need for changes to the existing Central Valley Water Board Water Quality Control Plans (Basin Plans) to facilitate salt disposal in a manner that is most beneficial to the region and consistent with the State Water Resources Control Board’s (State Water Board) Recycled Water Policy. This work is being conducted under the direction of the Central Valley Salinity Alternatives for Long-Term Sustainability (CV-SALTS) initiative, which is developing the SNMP for the Central Valley. The SSALTS project has been conducted in three phases (Figure 1-1): Phase 1: Identify and Characterize Existing Salt Accumulation Study Areas – The selection of representative study areas served as archetype situational examples to facilitate discussions regarding salt accumulation and disposal in the Central Valley. Each of these study areas was characterized to establish baseline information that was subsequently used to support development of salt disposal alternatives in Phases 2 and 3. Phase 2: Develop Potential Salt Management Strategies – Phase 2 of SSALTS developed potential long-term salt disposal alternatives in three parts: (1) in-valley alternatives; (2) out-of-valley alternatives; and (3) hybrid alternatives that combined in-valley and out-of valley salt disposal options. Phase 3: Evaluate Potential Salt Disposal Alternatives to Identify Acceptable Alternatives for Implementation – Alternatives developed under Phase 2 were evaluated in this report using selected feasibility criteria (e.g., regulatory, institutional, economic, technological, etc.). The outcome of this evaluation was the identification and prioritization of acceptable salt disposal alternatives for potential incorporation into Central Valley SNMP as salt management implementation measures. The Phase 1 and Phase 2 SSALTS final reports were submitted to the CV-SALTS Executive Committee in December 2013 and September 2014, respectively (CDM Smith 2013; CDM Smith 2014). The Phase 3 SSALTS draft report was submitted to the CV-SALTS Executive Committee in March 2015. Comments were received and incorporated into the Phase 3 SSALTS draft report. The Executive Committee recommended postponing the finalization of the Phase 3 SSALTS report until a draft of the Nitrate Implementation Measures Study (NIMS) report was completed, so that salt and nitrate implementation measures and mitigation strategies could be coordinated. While based on the March 2015 Phase 3 SSALTS draft report – and thus including the changes based on the March 2015 Phase 3 SSALTS draft report – and thus including the changes based on the original comments, the September 2016 Phase 3 SSALTS draft report had major changes in terms of content and structure. The September 2016 Phase 3 SSALTS draft report was sent to the Project Committee on September 20, 2016 and comments were received on October 5, 2016. The second set of comments were addressed and incorporated into this October 2016 Phase 3 SSALTS final report. Appendix E. provides the comments and responses on the September 2016 Phase 3 SSALTS draft report. The Phase 3 SSALTS report provides a path forward, based on the foundation of Phases 1 and 2 and CV-SALTS Executive Committee discussions.

State of the Salinas River Groundwater Basin

Monterey County Water Resources Agency (MCWRA) | January 16th, 2015

From 6.3 Steps Appropriate to Address Water Supply under Continued Drought Conditions:  Based on the continued large storage declines in the East Side and Pressure Su

From 6.3 Steps Appropriate to Address Water Supply under Continued Drought Conditions:  Based on the continued large storage declines in the East Side and Pressure Subareas (and resulting groundwater head declines and seawater intrusion), the current distribution of groundwater extractions is not sustainable. Seawater intrusion can account for up to 18,000 afy of the total storage loss of up to 24,000 afy. Sustainable use of groundwater can only be achieved by aggressive and cooperative water resources management. The consequences of no-action under continued drought conditions will be the imminent advancement of seawater intrusion within the next few years and the continued decline of groundwater head. Both of these conditions would necessitate the drilling of deeper groundwater wells, which may not be feasible in some areas because of lower groundwater yield and water quality in the Pressure Deep Aquifer. A more sustainable long-term management practice would encourage the Basin-wide redistribution and reduction of groundwater pumping, which would require cooperative and aggressive resource management. The unsustainability of the current distribution of groundwater extractions has long been recognized by various investigators, and a Basin-wide redistribution and reduction in pumping has been recommended previously (e.g. DWR, 1946). 6.3.1 Technical Option 1:  The large storage declines that have occurred in the Basin in the past, especially in the East Side Subarea, have created a significant landward groundwater head gradient that must be reversed before seawater intrusion can be halted. Reduction of pumping in the Pressure and East Side Subareas could help mitigate some of the anticipated effects of extended drought on groundwater storage and water quality in the study area. Shifting of pumping to areas further away from the coast would also be helpful, as long as it is shifted south of the current head trough (Figure ES3) that exists in the East Side Subarea. One of the main reasons that substantial steps must be taken to curtail seawater intrusion is that the large storage declines that have occurred in the Basin in the past (especially in the East Side Subarea) have created a significant landward groundwater head gradient that must be reversed before seawater intrusion can be halted. 6.3.2 Technical Option 2: The shifting of some pumping from the P-180 and P-400 Aquifers to the Pressure Deep Aquifer would reduce the storage deficit in the shallower aquifers; however, this would necessarily lead to head declines in the Pressure Deep Aquifer. Unlike the P-180 and P-400 Aquifers, it is not known whether or not the Pressure Deep Aquifer is hydraulically connected to the ocean in Monterey Bay, so it is not known whether this pumping shift would lead to the onset of regional seawater intrusion. Also unknown is the likelihood of localized interaquifer seawater mixing between the Pressure 400- Foot Aquifer and the Pressure Deep Aquifer. Hence, this Management Option requires more investigation to determine its feasibility. 6.3.3 Evaluation of Potential Solutions: The numerical modeling analysis to be performed as a second part of this Basin Investigation will consider the effects of various management decisions on the water supply and water quality in the study area. The primary questions to be assessed for each scenario are: 1) what will be the rate of groundwater head decline; and, 2) what will be the rate of increase in acreage with impaired water quality due to the advancement of the seawater intrusion front. We can then assess the economic effects of 1) and 2) due to water supply wells becoming inoperable (i.e. dry), and the further loss of aquifer storage capacity due to the advancement of seawater intrusion. The numerical model should be used to predict groundwater head declines under different management scenarios, including implementing targeted pumping rates and optimizing the distribution of pumping. Future declines in groundwater head must be evaluated by simulated groundwater conditions so that “trigger (groundwater) head levels” can be used as a measure of safe yield and an early alert system as part of Basin Management Objectives. That analysis will extend the discussions and conclusions presented in this report.

Statement of Findings regarding the Approval of the Ukiah Valley Basin Groundwater Sustainability Plan

California Department of Water Resources (DWR) | July 27th, 2023

Statement of Findings regarding the Determination of Incomplete Status of the Salinas Valley - Paso Robles Area Subbasin Groundwater Sustainability Plan

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

The Department of Water Resources (Department) is required to evaluate whether a submitted groundwater sustainability plan (GSP or Plan) conforms to specific requirements

The Department of Water Resources (Department) is required to evaluate whether a submitted groundwater sustainability plan (GSP or Plan) conforms to specific requirements of the Sustainable Groundwater Management Act (SGMA or Act), is likely to achieve the sustainability goal for the basin covered by the Plan, and whether the Plan adversely affects the ability of an adjacent basin to implement its GSP or impedes achievement of sustainability goals in an adjacent basin. (Water Code 10733.) The Department is directed to issue an assessment of the Plan within two years of its submission. (Water Code 10733.4.) This Statement of Findings explains the Department’s decision regarding the Plan submitted jointly by the City of Paso Robles Groundwater Sustainability Agency (GSA), the Paso Basin - County of San Luis Obispo GSA, the San Miguel Community Services District GSA, and the Shandon - San Juan GSA (collectively, the GSAs or Agencies) for the Salinas Valley - Paso Robles Area Subbasin (No. 3-004.06). Department management has reviewed the enclosed Staff Report, which recommends that the identified deficiencies should preclude approval of the GSP. Based on its review of the Staff Report, Department management is satisfied that staff have conducted a thorough evaluation and assessment of the Plan and concurs with, and hereby adopts, staff’s recommendation and all the corrective actions provided. The Department thus deems the Plan incomplete based on the Staff Report and the findings contained herein.

Statement of Findings regarding the Determination of Incomplete Status of the San Joaquin Valley – Eastern San Joaquin Subbasin Groundwater Sustainability Plan

California Department of Water Resources (DWR) | January 28th, 2022

The Department of Water Resources (Department) is required to evaluate whether a submitted groundwater sustainability plan (GSP or Plan) conforms to specific requirements

The Department of Water Resources (Department) is required to evaluate whether a submitted groundwater sustainability plan (GSP or Plan) conforms to specific requirements of the Sustainable Groundwater Management Act (SGMA or Act), is likely to achieve the sustainability goal for the basin covered by the Plan, and whether the Plan adversely affects the ability of an adjacent basin to implement its GSP or impedes achievement of sustainability goals in an adjacent basin. (Water Code   10733.) The Department is directed to issue an assessment of the Plan within two years of its submission. (Water Code 10733.4.) This Statement of Findings explains the Department’s decision regarding the Plan submitted by the Eastern San Joaquin Groundwater Authority (Authority), which is a joint powers authority formed by the 16 groundwater sustainability agencies (GSAs) located within the San Joaquin Valley – Eastern San Joaquin Subbasin (No. 5-022.01). Department management has reviewed the enclosed Staff Report, which recommends that the identified deficiencies should preclude approval of the GSP. Based on its review of the Staff Report, Department management is satisfied that staff have conducted a thorough evaluation and assessment of the Plan and concurs with, and hereby adopts, staff’s recommendation and all the corrective actions provided. The Department thus deems the Plan incomplete based on the Staff Report and the findings contained herein.

Statement of Findings regarding the Determination of Incomplete Status of the San Joaquin Valley – Kern County Subbasin Groundwater Sustainability Plans

California Department of Water Resources (DWR) | January 28th, 2022

The Department of Water Resources (Department) is required to evaluate whether a submitted groundwater sustainability plan (GSP) conforms to specific requirements of the

The Department of Water Resources (Department) is required to evaluate whether a submitted groundwater sustainability plan (GSP) conforms to specific requirements of the Sustainable Groundwater Management Act (SGMA), is likely to achieve the sustainability goal for the basin covered by the GSP, and whether the GSP adversely affects the ability of an adjacent basin to implement its GSP or impedes achievement of sustainability goals in an adjacent basin. (Water Code 10733.) The Department is directed to issue an assessment of the GSP within two years of its submission. (Water Code 10733.4.) SGMA allows for multiple GSPs implemented by multiple groundwater sustainability agencies (GSAs) and coordinated pursuant to a single coordination agreement that covers the entire basin to be an acceptable planning scenario. (Water Code   10727.) In the San Joaquin Valley – Kern County Subbasin (Subbasin), five separate GSPs were prepared by 11 GSAs pursuant to the required coordination agreement. This Statement of Findings explains the Department’s decision regarding the multiple GSPs covering the Subbasin submitted jointly by the multiple GSAs. Collectively, the five GSPs and the coordination agreement are referred to as the Plan for the Subbasin. Individually, the GSPs include the following: • Kern Groundwater Authority Groundwater Sustainability Plan (KGA GSP) – prepared by the Kern Groundwater Authority (KGA) GSA, Semitropic Water Storage District (SWSD) GSA, Cawelo Water District (CWD) GSA, City of McFarland GSA, Pioneer GSA, and West Kern Water District (WKWD) GSA. o Divided into 15 management areas, 22 sub-management areas. • Kern River Groundwater Sustainability Plan (Kern River GSP) – prepared by the Kern River GS and Greenfield County Water District GSA. o Divided into three management areas, 11 sub-management areas. • Buena Vista Water Storage District GSA Groundwater Sustainability Plan (BV GSP) – prepared by the Buena Vista Water Storage District (BV) GSA. o Divided into two management areas. • Olcese Groundwater Sustainability Agency Groundwater Sustainability Plan (Olcese GSP) – prepared by the Olcese Water District (OWD) GSA. • Henry Miller Water District Groundwater Sustainability Plan (Henry Miller GSP) – prepared by the Henry Miller Water District (HMWD) GSA. Department management has reviewed the enclosed Staff Report, which recommends that the deficiencies identified should preclude approval of the Plan. Based on its review of the Staff Report, Department management is satisfied that staff have conducted a thorough evaluation and assessment of the Plan and concurs with, and hereby adopts, staff’s recommendation and all the corrective actions provided. The Department thus deems the Plan incomplete based on the Staff Report and the findings contained herein.

Statement of Findings regarding the Determination of Incomplete Status of the San Joaquin Valley – KIngs Subbasin Groundwater Sustainability Plans

California Department of Water Resources (DWR) | January 28th, 2022

The Department of Water Resources (Department) is required to evaluate whether a submitted groundwater sustainability plan (GSP) conforms to specific requirements of th

The Department of Water Resources (Department) is required to evaluate whether a submitted groundwater sustainability plan (GSP) conforms to specific requirements of the Sustainable Groundwater Management Act (SGMA), is likely to achieve the sustainability goal for the basin covered by the GSP, and whether the GSP adversely affects the ability of an adjacent basin to implement its GSP or impedes achievement of sustainability goals in an adjacent basin. (Water Code § 10733.) The Department is directed to issue an assessment of the GSP within two years of its submission. (Water Code § 10733.4.) SGMA allows for multiple GSPs implemented by multiple groundwater sustainability agencies (GSAs) and coordinated pursuant to a single coordination agreement that covers the entire basin to be an acceptable planning scenario. (Water Code § 10727.) In the San Joaquin Valley – Kings Subbasin (Subbasin), seven separate GSPs were prepared by seven GSAs pursuant to the required coordination agreement. This Statement of Findings explains the Department’s decision regarding the multiple GSPs covering the Subbasin. Collectively, the seven GSPs and the coordination agreement are referred to as the Plan for the Subbasin. Individually, the GSPs include the following: • Central Kings Groundwater Sustainability Agency Groundwater Sustainability Plan (Central Kings GSP) – prepared the Central Kings GSA (CKGSA). • James Groundwater Sustainability Agency Groundwater Sustainability Plan (James GSP) – prepared by the James GSA (JGSA). • Kings River East Groundwater Sustainability Agency Groundwater Sustainability Plan (Kings River East GSP) – prepared by the Kings River East GSA (KREGSA). • McMullin Area Groundwater Sustainability Agency Groundwater Sustainability Plan (McMullin GSP) – prepared by the McMullin Area GSA (MAGSA). • North Fork Kings Groundwater Sustainability Agency Groundwater Sustainability Plan (North Fork Kings GSP) – prepared by the North Fork Kings GSA (NFKGSA). • North Kings Groundwater Sustainability Agency Groundwater Sustainability Plan (North Kings GSP) – prepared by the North Kings GSA (NKGSA). San Joaquin Valley – Kings Subbasin (Basin No. 5-022.08) • South Kings Groundwater Sustainability Agency Groundwater Sustainability Plan (South Kings GSP) – prepared by the South Kings GSA (SKGSA). Department management has reviewed the enclosed Staff Report, which recommends that the deficiencies identified should preclude approval of the Plan. Based on its review of the Staff Report, Department management is satisfied that staff have conducted a thorough evaluation and assessment of the Plan and concurs with, and hereby adopts, staff’s recommendation and all the corrective actions provided. The Department thus deems the Plan incomplete based on the Staff Report and the findings contained herein.

Statement of Findings regarding the Approval of the 180/400 Foot Aquifer Subbasin Groundwater Sustainability Plan

California Department of Water Resources (DWR) | June 3rd, 2021