Introduction

Welcome to the Los Angeles River California Environmental Flow Framework (CEFF) Project. This project provides the opportunity to convene watershed stakeholders over a 20-month structured decision-making process culminating in the development of flow recommendations for LA River. With joint support and funding from the Santa Monica Mountains Conservancy/Mountain Recreation and Conservation Authority (SMMC/MRCA), City of Los Angeles Sanitation and Department of Water and Power (LADWP), and anticipated funding from California Department of Fish and Wildlife (CDFW), this project will align the management goals driving the many policies, programs, and plans that will influence or rely on LA River flows and will address flow influences and needs across themes of biodiversity, cultural/tribal uses, flood control, recreation, urban cooling, water quality, and water supply.

California Environmental Flows Framework (CEFF)

The CEFF process was collaboratively developed by the State Water Board and scientists from academia, agencies, research organizations, and non-governmental organizations and officially introduced in 2021. It is comprised of three sequential sections:

Section A identifies existing management goals in the watershed and develops an understanding of the natural system.

Section B integrates extensive feedback from the public, as well as federal, state, and local agencies, to develop flow needs for the management goals, given existing conditions.

Section C develops a set of stakeholder-driven, comprehensive environmental flow recommendations that incorporate agreed-upon tradeoffs between stakeholders and systems to best balance their management goals via a Technical Working Group (TWG) process.

CEFF combines a strong technical basis (Sections A and B) with a collaborative TWG stakeholder engagement process (Section C) to reach a workable, consensus-driven strategy for flow management. The TWG will provide input and review throughout the project’s process.

The LA River CEFF Project Overview

Building upon the Los Angeles River Environmental Flows Project completed by Southern California Coastal Water Research Project (SCCWRP) in 2021, LA River CEFF is the next step to understanding the links between beneficial uses and river flow. Since September 2022, SMMC/MRCA has funded Stillwater Sciences to undertake the now-completed CEFF Section A for the mainstem LA River. Work on LA River CEFF Sections B and C has now begun. The LA River CEFF Sections B and C analysis is ongoing now and is informed by critical discussions among all key interested agencies, members of the public, and tribal parties, raising awareness and support among stakeholder organizations during the process. The CEFF process will guide the LA River CEFF Technical Working Group (TWG) through the development of scientifically defensible, consensus-driven environmental flow recommendations for the LA River that can balance water needs across the complete system, ideally identifying solutions that substantially improve all stakeholder priorities. The first LA River CEFF TWG met on June 11, 2024 and the second TWG meeting is planned for Fall 2024.

The expected outcome from the LA River CEFF Project is a fully framed set of environmental flow recommendations, accompanied by a range of credible management alternatives with a transparent analysis of the tradeoffs being made in support of each. The project’s environmental flow recommendations will inform the State Water Board’s decisions regarding the potential cumulative impacts of planned projects in the watershed on LA River flows and associated goals across the seven management themes from current and anticipated future requests for flow reduction.