• FloodMAR Network

*Operationalizing Functional Flows to Inform and Evaluate Flood-Managed Aquifer Recharge (Flood-MAR) Diversion Approaches* explores how recharge projects can incorporate ecological flow considerations when deciding when and how much water to divert.

Published in October 2026 by the Southern California Coastal Water Research Project (SCCWRP), with coauthors from Environmental Science Associates and The Nature Conservancy, the report applies the California Environmental Flows Framework (CEFF) to case studies in three Northern California watersheds: Scott River, Stony Creek, and Elder Creek. The Flood-MAR Network’s Instream Flows Action Team helped conceptualize the Scott River case study and provided early input.

The study compares functional flow-informed diversion criteria with the State Water Board’s “90/20” approach, a cumulative wet-season “80/50” approach, and, at Scott River, an approach based on relationships between flow and habitat conditions. It evaluates the volume, frequency, and duration of recharge opportunities alongside changes to ecologically important streamflow characteristics.

Results support a toolbox of diversion approaches tailored to local hydrology, ecosystem needs, operational capacity, and management priorities. No single approach performed best across all measures. The report provides a step-by-step evaluation framework to help practitioners compare alternatives and make transparent, site-specific decisions. A practical applications section discusses considerations for using alternative diversion criteria.

The analysis evaluates changes in streamflow characteristics rather than directly measuring ecological outcomes such as fish survival or population health. It offers a foundation for project planning and further study of how recharge diversions affect river ecosystems.

**Publication:** SCCWRP Technical Report 1501, October 2026.

• Environment - Terrestrial and Riparian/Aquatic
• Land Use Planning and Management
• People and Water