Climate-informed hydrologic modeling and policy typology to guide managed aquifer recharge

American Association for the Advancement of Science (AAAS) | April 21st, 2021

Harvesting floodwaters to recharge depleted groundwater aquifers can simultaneously reduce flood and drought risks and enhance groundwater sustainability. However, deploy

Harvesting floodwaters to recharge depleted groundwater aquifers can simultaneously reduce flood and drought risks and enhance groundwater sustainability. However, deployment of this multibeneficial adaptation option is fundamentally constrained by how much water is available for recharge (WAFR) at present and under future climate change. Here, we develop a climate-informed and policy-relevant framework to quantify WAFR, its uncertainty, and associated policy actions. Despite robust and widespread increases in future projected WAFR in our case study of California (for 56/80% of subbasins in 2070–2099 under RCP4.5/RCP8.5), strong nonlinear interactions between diversion infrastructure and policy uncertainties constrain how much WAFR can be captured. To tap future elevated recharge potential through infrastructure expansion under deep uncertainties, we outline a novel robustness-based policy typology to identify priority areas of investment needs. Our WAFR analysis can inform effective investment decisions to adapt to future climate-fueled drought and flood risk over depleted aquifers, in California and beyond.

Coachella Valley Water District Engineer's Report on Water Supply and Replenishment Assessment for the East Whitewater River Subbasin Area of Benefit

Coachella Valley Water District (CVWD) | April 15th, 2015

Coachella Valley Water District (CVWD) and Desert Water Agency (DWA) have been importing Colorado River water exchanged for State Water Project (SWP) water alloca

Coachella Valley Water District (CVWD) and Desert Water Agency (DWA) have been importing Colorado River water exchanged for State Water Project (SWP) water allocations to replenish the groundwater within the Coachella Valley Groundwater Basin since 1973. Groundwater replenishment within the East Whitewater River Subbasin began in 1997 through a pilot program at the Thomas E. Levy Groundwater Replenishment Facility (TEL Replenishment Facility). In 2004, the Martinez Canyon pilot project was brought online. If groundwater replenishment with imported water is eliminated, groundwater overdraft will result. Increased overdraft results in declining water levels, increased pump lifts, and increased energy consumption to pump groundwater for irrigation and domestic use. Extreme overdraft has the potential to cause ground surface subsidence and to impact water quality and groundwater storage volume.

Coastal Plain of Orange County, Basin 8-001 Alternative to a Groundwater Sustainability Plan

Orange County Water District (OCWD) | January 1st, 2017

Collaborative Governance and Environmental Justice: Disadvantaged Community Representation in California Sustainable Groundwater Management

Western Political Science Association | April 18th, 2019

A consistent critique of the theory and empirical research on collaborative governance is a lack of conceptualization and analysis of the role of political power and ine

A consistent critique of the theory and empirical research on collaborative governance is a lack of conceptualization and analysis of the role of political power and inequality (Foster 2002; Franks and Cleaver 2007; Morrison et al. 2017; Purdy 2012). The critique is more broadly applied to public policy and institutional analysis in general (Knight 1992; Moe 2005), and has implications the democratic legitimacy of governance arrangements (Alexander, Doorn, and Priest 2018). Political institutions provide differential access to decision-making (Besley and Case 2003), while political groups and individuals have higher or lower capacity to participate in governance systems and influence the outcomes (Olson 2009; Sabatier and Jenkins-Smith 1993; Stigler 1971). Thus, there continues to be a need for empirical research focused on the crucial issue of how these factors affect the structure and function of governance institutions. This article contributes to this discussion by analyzing the representation of disadvantaged communities in the 2014 Sustainable Groundwater Management Act (SGMA) in California.

Colorado River Hydrologic Region Groundwater Update

California Department of Water Resources (DWR) | April 1st, 2015

The primary goal of the Colorado River Hydrologic Region (Colorado River region) groundwater update is to expand information about region-specific groundwater conditions

The primary goal of the Colorado River Hydrologic Region (Colorado River region) groundwater update is to expand information about region-specific groundwater conditions for California Water Plan Update 2013, and to guide more informed groundwater management actions and policies. A second goal is to steadily improve the quality of groundwater information in future California Water Plan (CWP) updates to a level that will enable regional water management groups (RWMGs) to accurately evaluate their groundwater resources and implement management strategies that can meet local and regional water resource objectives within the context of broader statewide objectives. The final goal is to identify data gaps and groundwater management challenges meant to serve as a guidepost for prioritizing future data collection and funding opportunities relevant to the region. This regional groundwater update is not intended to provide a comprehensive and detailed examination of local groundwater conditions, or be a substitute for local studies and analysis. Where information is readily available, the update does report some aspects of the regional groundwater conditions in greater detail.

Colusa County | Managed Aquifer Recharge: benefitting aquifers, farmers, and migratory birds

Nature Conservancy | September 3rd, 2018

In partnership with growers and the Colusa Groundwater Authority (CGA), The Nature Conservancy (TNC) is implementing a pilot multiple-benefit managed aquifer r

In partnership with growers and the Colusa Groundwater Authority (CGA), The Nature Conservancy (TNC) is implementing a pilot multiple-benefit managed aquifer recharge (MAR) program on farmland in California’s Central Valley, Colusa County. This program will benefit local groundwater users by replenishing critical domestic and agricultural groundwater supplies in a Severely Disadvanateged Community (SDAC). Participating farmers will benefit economically through incentive payments, and migratory shorebirds will benefit through the creation of critical winter habitat on farms through our specific field and water depth specificiations. MAR sites will be selected where and when it is appropriate and cost-effective to do so based on farming practices, soil suitability, water availability, basin water balances, and migratory/shorebird habitat requirements. The relevance and success of this program for Groundwater Sustainability Agencies (GSAs), Severely Disadvantaged Communities (SDACs), and Groundwater Sustainability Plans (GSPs) will require all of these stakeholders and project participants to collaborate on its design. Thus, TNC will engage growers, water managers, and other stakeholders in a variety of formal and informal ways to ensure that this program will meet the needs of all parties involved in GSP development. This program serves as a model for other GSAs and stakeholders seeking to deliver multiple benefits through on-farm recharge in the Central Valley where such a program is appropriate.

Colusa Subbasin Groundwater Sustainability Plan

Colusa Groundwater Authority | December 3rd, 2021

The purpose of this GSP is to characterize groundwater conditions in the Subbasin, evaluate and report on existing conditions relating to the six sustainability indicator

The purpose of this GSP is to characterize groundwater conditions in the Subbasin, evaluate and report on existing conditions relating to the six sustainability indicators, describe existing monitoring, 14 management programs and policies relating to groundwater resource use, document public outreach and communication, establish sustainability goals, and describe projects and management actions (PMAs) the GSAs will implement to achieve sustainable groundwater management within 20 years of implementing the GSP. Due to size, this file has been divided into 16 parts Part 1, Part 2, Part 3, Part 4, Part 5, Part 6, Part 7, Part 8, Part 9, Part 10, Part 11, Part 12, Part 13, Part 14, Part 15, Part 16

Comment on “Short-lived pause in Central California subsidence after heavy winter precipitation of 2017” by K. D. Murray and R. B. Lohman

American Association for the Advancement of Science (AAAS) | June 12th, 2019

In a study by Murray and Lohman (M&L), the authors suggest that remote sensing data are useful for monitoring land subsidence due to aquifer system compacti

In a study by Murray and Lohman (M&L), the authors suggest that remote sensing data are useful for monitoring land subsidence due to aquifer system compaction. We agree. To infer aquifer dynamics, we provide a more detailed and joint analysis of deformation and groundwater data. Investigating well data in the Tulare Basin, we find that groundwater levels stabilized before 2015 and show that M&L’s observed continued subsidence through July 2016 is likely caused by the delayed compaction of the aquitard. Our analysis suggests the observed 2017 transient uplift is not due to recharge of the aquifer system after heavy winter rainfall because it requires an unrealistic vertical hydraulic gradient nearly five orders of magnitude larger than that typical of Tulare Basin. We find that, regardless of the amount of rainfall, transient annual uplifts of ~3 cm occur in May to June. Using an elastic skeletal storage coefficient of 5 × 10−3, we link this ground uplift to annual groundwater level changes.

Communities that rely on a contaminated groundwater source for drinking water

California State Water Resources Control Board (SWRCB) | January 1st, 2013

AB 2222 (Caballero, Chapter 670, Statutes of 2008) requires the State Water Resources Control Board to submit a report to the Legislature that identifies: 1) communities

AB 2222 (Caballero, Chapter 670, Statutes of 2008) requires the State Water Resources Control Board to submit a report to the Legislature that identifies: 1) communities in California that rely on contaminated groundwater as a primary source of drinking water; 2) the principal contaminants and other constituents of concern; and 3) potential solutions and funding sources to clean up or treat groundwater or provide alternative water supplies. A “community,” for the purposes of this report, is defined as a Community Public Water System (Health and Safety Code Section 116395). When this report refers to communities that rely on a contaminated groundwater source, it is referring to community public water systems that draw water from a contaminated groundwater source prior to any treatment. Over 95 percent of the 38 million Californians get their drinking water from a public water system. The findings in this report do not reflect private domestic wells or other unregulated water systems since the state does not require these groundwater users to sample their wells, and consequently a comprehensive database for these groundwater sources does not exist. This report identifies 680 community water systems that, prior to any treatment, relied on a contaminated groundwater source during the most recent California Department of Public Health (CDPH) compliance cycle (2002-2010). It is important to note that, according to CDPH, over 98% of Californians on public water supply are served safe drinking water. Although many water suppliers draw from contaminated groundwater sources, most suppliers are able to treat the water or blend it with cleaner supplies before serving it to the public. Consequently, when this report refers to communities that rely on contaminated groundwater, it is referring to community public water systems that draw water from one or more contaminated groundwater wells prior to any treatment or blending. Some community water systems, however, cannot afford treatment or lack alternative water sources, and have served water that exceeds a public drinking water standard. Of the 680 community water systems that rely on a contaminated groundwater source, 265 have served water that exceeded a public drinking water standard during the most recent CDPH compliance cycle (2002-2010).

Community Perspectives and Environmental Justice in California's San Joaquin Valley

University of California, Merced | December 1st, 2022