Flood-MAR Resources

Flooding rice fields in Yuba County with groundwater (DWR, 2009).


This section contains guidance on how to approach a Flood-MAR project. This includes fact sheets, resources on funding, permitting information, and more.
Link to Table View of All Guidance

The California Department of Water Resources (DWR) prepared this white paper to explore opportunities to use flood water for managed aquifer recharge (Flood-MAR) because DWR recognizes the need to rehabilitate and modernize water and flood infrastructure in California.

Through this guide, California almond growers can begin evaluating their options for addressing local sub-basin overdraft through recharge, helping secure reliable, sufficient, and drought resilient groundwater supplies. In areas where soil conditions are suitable and excess water is available, ground water recharge represents one of the most cost-effective methods to increase storage, thereby ensuring water supply and improving water quality.

This document represents a first step towards management guidance for on-farm recharge planners and practitioners to maximize benefits to water quality and to manage risks under AgMAR. This document is also intended to be used as a resource for communities so they can more fully participate in the GSA decision-making process.


This section includes published research papers relevant to Flood-MAR.
Link to Table View of All Research

This Flood-MAR Research and Data Development Plan (R&DD Plan) presents the work of the Flood-MAR Research Advisory Committee (RAC), a multidisciplinary group of subject matter experts across 13 research themes. The RAC was tasked to identify the research, data, guidance, and tools necessary to support and expand the implementation of Flood-MAR projects.

To determine the impact of unsaturated-zone stratigraphic heterogeneity on MAR effectiveness, we simulate recharge at a Central Valley almond orchard surveyed with a towed transient electromagnetic system. First, we identified three outcomes of interest for MAR sites: infiltration rate at the surface, residence time of water in the root zone and saturated-zone recharge efficiency, which is defined as the increase in saturated-zone storage induced by MAR.

Groundwater is a critical component of California’s water supply portfolio. Due to excessive pumping, many groundwater basins have been depleted, causing undesirable results. The passage of the Sustainable Groundwater Management Act (SGMA) in 2014 requires Groundwater Sustainability Agencies to implement strategies to bring groundwater use to sustainable levels.

Tools and Data

This section features Flood-MAR related data, modeling tools, maps, and more.
Link to Table View of All Tools and Data

The Department of Water Resources is conducting airborne electromagnetic (AEM) surveys in California’s high- and medium-priority groundwater basins, where data collection is feasible, to assist local water managers as they implement the Sustainable Groundwater Management Act (SGMA) to manage groundwater for long term sustainability.

The Soil Agricultural Groundwater Banking Index (SAGBI) is a suitability index for groundwater recharge on agricultural land. The SAGBI is based on five major factors that are critical to successful agricultural groundwater banking: deep percolation, root zone residence time, topography, chemical limitations, and soil surface condition.

As part of DWR’s technical assistance to Groundwater Sustainability Agencies (GSAs), other water managers, and the public, DWR has developed the SGMA Data Viewer. The SGMA Data Viewer provides access to groundwater-related datasets that are organized by the requirements of SGMA and the Groundwater Sustainability Plan (GSP) regulations for the purposes of supporting GSP development and implementation.


This section links to resources such as Flood-MAR in the news, relevant policies, guidelines, recommendations and more.
Link to Table View of All References

The historic passage of SGMA in 2014 set forth a statewide framework to help protect groundwater resources over the long-term. SGMA is comprised from a three-bill legislative package, including AB 1739 (Dickinson), SB 1168 (Pavley), and SB 1319 (Pavley), and subsequent statewide Regulations. In signing SGMA, then-Governor Jerry Brown emphasized that “groundwater management in California is best accomplished locally.”

The purpose of the Groundwater Resource Hub is to help local agencies achieve sustainable groundwater management by providing the science and tools needed to help address nature’s water needs. Over time, the goal is to improve statewide and local understanding of nature’s groundwater needs to reduce uncertainties and therefore enhance sustainable groundwater management.

The Groundwater Exchange is a central, collaborative, and publicly accessible online resource center connecting water managers, water users, and community members with tools and resources to support the design and implementation of effective Groundwater Sustainability Plans under California’s Sustainable Groundwater Management Act.

Flood-MAR Videos

Community Informed Planning for Multibenefit Recharge Projects through MLRP (Lunch-MAR | May 2024)

The Multibenefit Land Repurposing program has completed its first full year in 2023 and is turning a critical corner - we're coming out of the "storming" phase and seeing coordinated land repurposing efforts "forming". This discussion will offer an update on the intention, structure, and status of the program, and expand on the experience of the Kaweah Water District using the program to integrate habitat restoration and community benefits into high impact groundwater recharge projects.


Understanding and Minimizing Arsenic Mobilization during MAR (Lunch-MAR | April 2024)

While managed aquifer recharge (MAR) offers numerous potential benefits to water supply, geochemical shifts during MAR can mobilize toxic, naturally occurring contaminants from sediments to groundwater, threatening the viability of MAR as a water management strategy. This presentation describes geochemical drivers of arsenic mobilization during MAR using example field studies in California. Additionally, we provide an overview of general guidance developed for the state of Texas to limit arsenic

Engineering With Nature on the Pajaro River for GW Recharge & Flood Protection (Lunch-MAR | March 2024)

Julie Beagle and Dr. Mark Strudley discuss how Engineering With Nature strategies and design elements injected into the design of the Pajaro River at Watsonville levee reconstruction project position the project to achieve multi-benefit flood risk reduction, including enhancement of groundwater recharge. Partnership between local (PRFMA), State (DWR Flood-Mar Group), and federal (USACE) agencies afford the opportunity to use unique design tools, including the EcoFIP toolkit (Ecological Floodpla