The Sustainable Groundwater Management Act (SGMA) requires that a Groundwater Sustainability Agency prepare a Groundwater Sustainability Plan that lays out the path that the basin will take to achieve sustainable groundwater management within 20 years. The path for preparing a Groundwater Sustainability Plan is discussed below.
Notice of Intent to Prepare a Groundwater Sustainability Plan
The first step for a Groundwater Sustainability Agency to prepare a Groundwater Sustainability Plan is to notify the Department of Water Resources.
Notification to the Department should contain general information about the process for developing the plan including how interested stakeholders may participate. This information must also be posted on the Groundwater Sustainability Agency’s website.
For more information:
- For more information on Groundwater Sustainability Plan Initial Notifications, click here.
- To submit an agency’s initial notification or to view already initial notifications already submitted, click here.
- For instructions on using the GSP Initial Notification System, click here to view a webinar or click here to review the presentation.
- Click here for a FAQ on the GSP Initial Notification Requirements.
Stakeholder Outreach and engagement
SGMA requires GSAs to consider the interests of many beneficial users and uses of groundwater, including overlying groundwater rights holders (both agricultural users and domestic well owners), municipal well owners, public water systems, local land use planning agencies, environmental users of groundwater, surface water users, the federal government, Native American tribes, and disadvantaged communities (DACs).
Facilitation Support Services available
Sometimes GSAs need the help of professional facilitators to foster discussions among diverse water management interests and local agencies. The Department of Water Resources offers facilitation support services to help GSAs work through challenging water management situations.
Stakeholder Communication and Engagement (Department of Water Resources) Examples and resources to engage stakeholders in Groundwater Sustainability Plan (GSP) preparation.
Engagement with Tribal Governments (Department of Water Resources) Resources for GSAs to engage California’s Tribal governments, including those on Tribal lands not subject to SGMA.
Outreach and Engagement - A Resource Management Strategy for the California Water Plan (Department of Water Resources and California Natural Resources Agency) Engagement tools for water agencies.
Collaborating for Success - Stakeholder Engagement for SGMA Implementation: (Community Water Center) Statutory requirements for stakeholder engagement in SGMA, including examples of best practices and collaborative management.
Inclusive Public Engagement (Institute for Local Government) Resources for successful and inclusive public engagement.
Open and Public V - A Guide to The Ralph M Brown Act (League of California Cities) Explains the current provisions of California statutes and case law as of April 2016 and includes an annotated copy of the Brown Act.
Publications in Spanish
Documento Guia para el GSP - Comunicacion y Participacion de los Interesados, (DWR) Este documento guía ofrece a las agencias de Sostenibilidad del Agua Subterránea (GSA) información útil para la comunicación y participación de los interesados en la elaboración del Plan de Sostenibilidad del Agua Subterránea (GSP).
Guia de Reglamentos de Emergencia para Planes de Sostenibilidad del Agua Subterranea (DWR) El propósito legislativo de la histórica SGMA de 2014 es que las agencias públicas locales y las recién formadas GSA gestionen el agua subterránea de manera sostenible en las cuencas subterráneas de California.
Participe en el manejo de su cuenca: Guía para entender los planes de sustentabilidad de aguas subterráneas de California, (CWC & Union of Concerned Scientists) ASK INTERPRETER FOR A ONE LINE DESCRIPTION
Templates, outlines, and examples
Stakeholder Engagement Chart for Identifying GSP Audiences - (Department of Water Resources) A table of potential interests for GSA engagement activities.
Stakeholder Survey Template – (Department of Water Resources) Questions for understanding stakeholder interests, issues, and challenges.
Communication and Engagement Plan Outline (Department of Water Resources) A sample communication and engagement plan for GSAs.
Community Groundwater Management Worksheet – (Community Water Center) Helps stakeholders identify information relevant to SGMA implementation.
Some examples of stakeholder communication
- Agenda example from Eastern San Joaquin County Groundwater Basin Authority
- Basin Factsheet example from the Upper Ventura River GSA
- Advisory Committee example from the Santa Cruz Mid-County Groundwater Agency
- Spanish SGMA materials example from the Salinas Valley Groundwater work group
- Bilingual GSA Factsheet example from the North Fork GSA
- Mailing list sign up example from the Kern Groundwater Authority
BMP 3 Hydrogeologic Conceptual Model (Department of Water Resources)
BMP 4 Water Budget (Department of Water Resources)
Once of the first steps in GSP development is preparation of your “Basin Setting”, which requires GSAs to undertake four main tasks:
- Develop a hydrogeologic conceptual model,
- Describe groundwater conditions,
- Develop a water budget, and
- Describe management areas within the basin.
Additional information about each of these components is provided below.
Develop a hydrogeologic conceptual model
The basin setting is summarized in a hydrogeological conceptual model, which describes a basin’s hydrology, land use, geology, water quality, and aquifer structure. The hydrogeologic conceptual model must have both a narrative and graphical form.
For more information on creating a hydrogeological model, see:
- Hydrogeological Conceptual Model BMP (Department of Water Resources)
- Hydrogeological Conceptual Models: Developing, Testing, and Communicating (Power Point Presentation)
Describe Groundwater Conditions
Current and historical and groundwater conditions in a basin must be developed using the best available science and must include information about groundwater elevation data, seawater intrusion, groundwater quality issues, land subsidence, interconnected surface waters, and groundwater dependent ecosystems.
For more information on providing information on groundwater dependent ecosystems, see: Guidance for including GDEs in Sustainable Groundwater Management (The Nature Conservancy)
Develop a water budget
GSPs must include a water budget for the basin that provides an accounting and assessment of the total annual volume of groundwater and surface water entering and leaving the basin, including historical, current and projected water budget conditions, and the change in the volume of water stored. Water budget information must be reported in both tabular and graphical form.
For more information on developing a water budget, see:
- GSP Regulations on basin setting, hydrogeological conceptual models, and water budgets
- Water budget BMP (Department of Water Resources BMP)
- Water Budgets: Foundations for Effective Water Resource Management (US Geological Survey)
Describe management areas
GSAs may choose to have one or more management areas in their basin. Management areas may define different minimum thresholds and be operated to different measurable objectives than the basin at large, provided that undesirable results are defined consistently throughout the basin.
For more information on management areas:
Hydrologic Groundwater Modeling
Projecting Forward: A Framework for Groundwater Model Development under SGMA (Water in the West)
Adjudicating Groundwater: A Judge’s Guide to Understanding Groundwater and Modeling (The National Judicial College)
A model is a simplification of a system. The term hydrologic model can be used to refer to everything from a physical model of a watershed to an integrated surface water groundwater computational model. In all cases a hydrologic model is a term used to describe a model or simplification of a complex system.
Under SGMA the term model most commonly refers to either 1) hydrogeologic conceptual models, which are described in the above section under basin setting], or 2) mathematical hydrologic models used to understand hydrologic systems. This section provides a brief overview of mathematical hydrologic models.
Mathematical hydrologic models
Hydrologic models use equations to represent surface water hydrology and the groundwater systems to which they are connected. They use model codes, which are then tailored to a specific site using a particular set of governing equations, parameters, and boundary conditions. For example, working with the USGS, Santa Clara Valley Water District used the MODFLOW-2000 model code to develop a hydrologic model for its district. This model is referred to as the Santa Clara Valley Regional Ground-Water/Surface-Water Flow Model.
While models are a simplification of reality, they can serve as powerful tools to develop a better understanding of hydrologic systems, reliable estimates of groundwater budgets, identify data gaps, forecast the outcome of future management actions on a groundwater basin, and explore alternative management strategies. Models provide the link between established management criteria and the management approaches necessary to achieve them.
That being said, developing useful, predictive models capable of simulating the potential changes resulting from changes in management actions take significant data, time, energy, technical expertise, and financial resources to develop. Agencies should work closely with model developers to understand what data are available, and to ensure that model development is consistent with the data in a basin. Finally, hydrologic models do not provide as a single “true” value, rather they provide potential outcomes. Agencies using hydrologic models for management decisions should work with the model developer to understand model uncertainty, its sources, and the potential range of possible outcomes.
Reports and Publications
Ask CWL for documents with keywords groundwater and modeling.
Establish Management Criteria
Sustainable Management Criteria BMP - Draft (Department of Water Resources)
Measuring What Matters: Setting Measurable Objectives to Achieve Sustainable Groundwater Management in California (Union of Concerned Scientists)
Achieving sustainable groundwater management under SGMA requires GSAs to 1) establish a basin-wide sustainability goal, and 2) avoid the six Undesirable Results (URs).
Developing minimum thresholds (the point below which URs occur) and measurable objectives are required components a sustainability goal.
Define your Sustainability Goal
Every basin subject to SGMA must develop a basin-wide sustainability goal that culminates in the absence of undesirable results within 20 years of GSP implementation. The sustainability goal must include a plan and measures to ensure it is met within 20 years of a plan's implementation and maintained over the 50-year planning horizon.
Avoiding the six undesirable results - surface water depletion, storage reduction, degraded water quality, seawater intrusion, land subsidence, and lowering groundwater levels - is the central tenet of SGMA.
Minimum thresholds are set using a numeric value that represent a point in the basin that, if exceeded, may cause undesirable results. Development of minimum thresholds is required at the local level using information developed in the hydrogeologic conceptual model, the description of current and historical groundwater conditions, and the water budget.
Groundwater Sustainability Plans should set one or more measurable objective for each "sustainability indicator," or each of the undesirable results. Measurable objectives should include interim milestones set at five year intervals. The goal is eliminating undesirable results within 20 years of implementation of the plan (see below for definition).
Definitions of key terms
“Sustainability indicator:” effects caused by groundwater conditions occurring throughout the basin that, when significant and unreasonable, cause undesirable results, as described in Water Code Section 10721(x).
“Minimum threshold:” a numeric value for each sustainability indicator used to define undesirable results.
“Measurable objectives:” specific, quantifiable goals for the maintenance or improvement of groundwater conditions that have been included in an adopted Plan.
“Interim milestone” (IM): refers to a target value representing measurable groundwater conditions, in increments of 5 years, set by an Agency as part of a Plan.
“Baseline” or “baseline conditions:” historic information used to project future conditions for hydrology, water demand, and availability of surface water and to evaluate potential sustainable management practices of a basin.
Incorporating Climate Change
Guidance for Climate Change Data Use During Sustainability Plan Development (Department of Water Resources)
Navigating a Flood of Information (2017) - Evaluating and Integrating Climate Science into Groundwater Planning in California (Union of Concerned Scientists, Stanford Water in the West)
Climate change is already having a significant impact on water resources throughout the globe, resulting in more severe and prolonged droughts, increased flooding, changes in the timing and intensity of precipitation, sea level rise, and a host of other impacts. Scientists predict these impacts will become increasingly intense and less predictable under climate change.
To help GSAs anticipate and plan for these impacts, GSPs must include quantitative climate change analysis into their planning process. Specifically, water budgets must include projected hydrology, water demand, and surface water supply account for climate change (CCR §354.18(3)).
Avoiding Undesirable Results
SGMA requires GSAs to develop and implement GSPs
to avoid the six undesirable results listed below:
Declining groundwater levels
Chronic lowering of groundwater levels indicating a significant and unreasonable depletion of supply
Reduction of Groundwater Storage
Significant and unreasonable reduction of groundwater storage
Significant and unreasonable land subsidence that substantially interferes with surface land uses
Significant and unreasonable seawater intrusion
Depletions of interconnected surface water that have significant and unreasonable adverse impacts on beneficial uses of the surface water
Significant and unreasonable degraded water quality
Projects and Actions (Increase supply, Reduce Demand)
Most Groundwater Sustainability Agencies will need to increase supply, manage demand, or do both to achieve sustainable groundwater management under SGMA.
Below are some potential actions that a GSA may undertake:
Groundwater recharge describes natural or artificial replenishment of an aquifer. Recharge can occur naturally through precipitation, runoff or surface water infiltration or artificially via spreading basins, injections wells, conjunctive management and irrigation return flow.
Conjunctive use refers to the coordinated management of both surface and groundwater resources as a single source. Reliance on groundwater in dry in years is offset by managed recharge of aquifers in year with above average precipitation.
Once thought of as a nuisance, stormwater is now being seen as a source for recharging depleted groundwater basins.
Wastewater can be treated for groundwater recharge or landscape irrigation.
Agricultural Water Use efficiency
Ongoing improvements in agricultural water use efficiency have resulted from technological improvements in watering infrastructure, the integration of real-time monitoring, and a better understanding of crop water requirements.
Urban Water Use Efficiency
Tiered water rates, outdoor water use regulations, landscape reform programs, and rebates on efficient indoor appliances are some of the tools being employed by cities to reduce consumption.
Markets and Trading
Water markets and trading can provide flexibility in managing water supplies. Trading goes by many different names, including markets, cap and trade, transfers, credit programs, banking, pooling, and exchanges.
water allocation schemes
In some basins, GSAs may choose to develop groundwater allocation schemes to ensure that GSPs meet their sustainability goal and avoid state intervention.
Monitoring and Data Management
BMP 1: Monitoring Protocols Standards and Sites (Department of Water Resources)
BMP 2: Monitoring Networks and Identification of Data Gaps (Department of Water Resources)
Groundwater monitoring is at that the heart of the Sustainable Groundwater Management Act (SGMA). Monitoring networks provide the foundation for developing an understanding of current conditions in the basin and how they are changing through time. Under SGMA, Groundwater Sustainability Agency (GSA) must develop a groundwater monitoring network that “promotes the collection of data of sufficient quality, frequency, and distribution to characterize groundwater and related surface water conditions in the basin…”
Each Groundwater Sustainability Plan (GSP) must include a description of the monitoring network objectives for the basin, including how the network will be developed and implement to ensure evaluate progress toward the basin’s sustainability goal.
To be compliant with SGMA, monitoring networks must be able to demonstrate progress toward achieving the measurable objectives, monitor impacts to beneficial users of groundwater, monitor changes in groundwater conditions relative to measurable objectives and minimum thresholds, and quantify changes in water budget components. Additionally, the networks must collect sufficient data to demonstrate short-term, seasonal, and long-term trends in groundwater and related surface conditions.
Monitoring networks must monitor for all six sustainability criteria unless the GSA has demonstrated that undesirable results for the sustainability criteria are unlikely to occur. GSPs must include the quantitative values for minimum threshold, measurable objectives, and interim milestones for each sustainability criteria, that will be measured at each monitoring site.
An agency may designate a subset of monitoring sites as representative of conditions in the basin or area of a basin. Additionally, groundwater elevations can be used as a proxy for monitoring other sustainability indicators if significant correlation between groundwater level and the sustainability indicator can be shown.
Assessment and Improvement of Monitoring Networks
The GSP and each five-year update must include an evaluation of the monitoring network, a determination of uncertainty, and identification of data gaps and the steps the agency plans to take to address those uncertainties or data gaps.
Reporting Monitoring Data
Monitoring data must be stored in a data management system and a copy of the monitoring data included in the Annual Report and submitted electronically to the Department.
Coordination and Interbasin Agreements
In basins with multiple GSPs, a single Coordination Agreement must be submitted with the GSPs to DWR. The coordination agreement ensures that GSPs are developed and implemented using consistent data, methodologies, and objectives.
The Coordination Agreement must demonstrate how multiple GSPs will jointly achieve the basin’s sustainability goal. Additionally, it must include the responsibilities of each GSA in the basin; the procedures for exchanging information and resolving conflicts;and a description of the data, methodologies, and assumptions used in GSP development.
Interbasin Agreements, agreements between adjacent basins, are not required under SGMA. Two or more GSAs may enter into an Interbasin Agreement to establish compatible goals and understandings regarding fundamental elements of each GSP.
Interbasin agreements can be used where a groundwater hydraulic connection exists between basins to share technical information and provide a process for resolving conflicts. Interbasin agreements can also be included in a GSP to support findings that a implementing a basin's GSP will not adversely affect an adjacent basin's ability to implement their GSP.
Put it in writing and submit to the department of water resources
When you have finished your Groundwater Sustainability Plan (GSP), it must then be submitted to the Department of Water Resources.
All groundwater basins that are designated high or medium priority must submit their completed GSPs by January 31, 2022. Groundwater basins designated as critically overdrafted must submit their completed GSPs by January 31, 2020.
Once submitted, the Department has two years to review the plan. A GSP may be deemed inadequate if the Department, in consultation with the State Board, determines that the GSP is inadequate or if it is not being implemented in a manner that will likely achieve the sustainability goal. If it is found inadequate, GSAs have one year to address the deficiencies or the State Board may develop an interim plan for the basin.
Groundwater Sustainability Plan Templates and Frameworks
Groundwater Sustainability Plan Annotated Outline (Department of Water Resources)
Basin Framework for a Multi-benefit Groundwater Replenishment and Water Trading Program: Groundwater Sustainability Plan Chapter Templates (Environmental Defense Fund, New Current Water and Land LLC)