Flood-Managed Aquifer Recharge (Flood-MAR)

DWR’s Watershed Studies explore two Flood-MAR strategies and examine how changing flood patterns, water supply, and ecosystem health can be jointly managed through coordinated recharge and reservoir operations. The Watershed Studies were conducted to see how they could help water managers reduce climate change risks and build resilience for communities, farms, and the environment.

DWR isworking with partners to develop a systematic approach to identify floodplain restoration and expansion opportunities that provide high-quality salmonid habitat and enhance naturally occurring floodplain recharge. The pilot study tools help visualize and compare conceptual restoration designs for potential habitat and recharge benefits and quantify potential benefits and implementation costs. For more information, check out the links below:

Multiple Benefit Floodplain Restoration Pilot Studies Overview

Upper San Joaquin Study Phase I

Upper San Joaquin Study Phase II

Upper San Joaquin Study Factsheet

Pajaro Regional Flood Risk Management Project

Cosumnes River Pilot Study Summary

Merced River Watershed Flood-MAR Reconnaissance Study

To better understand climate vulnerabilities and how to address them, the California Department of Water Resources (DWR) conducted a three-year Merced study in partnership with Merced Irrigation District (MID) as a proof of concept to explore the effectiveness of Flood-MAR to concurrently reduce flood risk, improve water supply, and enhance ecosystems in the Merced River watershed, a tributary to the San Joaquin River. The Merced study is an exploratory watershed-scale analysis to develop and test analytical methods and models, assess climate change vulnerability, and evaluate adaptation strategies meeting multiple benefits that achieve these shared objectives:

1. Assess watershed vulnerability to climate change for flood protection, water supply, and ecosystems.
2. Develop Flood-MAR strategies reflecting a range of operational complexity and infrastructure improvements.
3. Quantitatively evaluate the performance of Flood-MAR strategies in providing multi-sector benefits and climate resilience.

First Of Its Kind Watershed Study Highlights How Innovative Tools Can Help Build Climate Resilience in the San Joaquin Valley

Following is the Merced River Watershed Flood-MAR Reconnaissance Study Report and supporting technical information records (TIR) that explain the development as well as the results of the study:

• Merced River Watershed Flood-MAR Reconnaissance Study Report
• TIR 1 Plan of Study
• TIR 2 Model Integration
• TIR 3 Climate Change Vulnerability Assessment and Baseline Assumptions
• TIR 4 Adaptation Strategy Performance

TheFlood-MAR Research and Data Development Plan (R&DD Plan) was created by a team of subject matter experts across 13 research themes who identified the research, data, guidance, and tools necessary to support and expand the implementation Flood-MAR projects. There has been a lot of progress since the plan was developed, and an evaluation outlines the advances made on its 39 key actions while also pointing to dozens of resources created to support broader use of Flood-MAR.

Theme-specific Actions and Documentation are available by request to FloodMAR@water.ca.gov.

Coordinating Flood and Groundwater Management Brochure

Learn more about how Flood-MAR can reduce flood risk, boost groundwater recharge, and support climate adaptation by strengthening coordination between flood and groundwater management.

2018Flood-MAR White Paper

Explore how large-scale Flood-MAR implementation can help rehabilitate and modernize California’s water and flood infrastructure.

The following websites provide additional information and resources on the benefits and issues of using flood waters to recharge groundwater basins.

• California Department of Agriculture (CDFA)
• State Water Resources Control Board (SWRCB)
• University of California, Agriculture and Natural Resources
• UC Water
• Groundwater Resource Hub