Los Angeles Basin Study

Summary Report

Quick Links - Study Background
Plan of Study
Fact Sheet

Task 2 - Water Supply & Demand Analysis
Final Report

Task 3 - Climate Change Analysis
Task 3.1 - Development of Climate-Adjusted Hydrologic Model Inputs
Task 3.1 - Climate Change and Hydrologic Projections Appendices
Task 3.2 - Hydrologic Modeling Report
Task 3.2 - Annual Hydrologic Results Workbook

Task 4 - Existing Infrastructure Response & Operations Guidelines Analysis
Final Report

Task 5 - Infrastructure & Operations Concept Analysis
Final Report
    Appendix A - Infrastructure and Operations Concepts (Excel)
    Appendix B - Local Stormwater Capture (PDF)
    Appendix C - Modeling Approach and Solutions (PDF)
    Appendix D - Local Management Cost (Excel)
    Appendix D - Regional 1 Cost (Excel)
    Appendix D - Regional 2 Cost (Excel)
    Appendix D - Regional 3 Cost (Excel)
    Appendix D - Storage 3 Cost (Excel)
    Appendix E - LACFCD Dam Hydrology and Cost Estimates (PDF)

Task 6 - Trade-off Analysis
Final Report

Outreach Info
     Task 6 Trade-Off Analysis & Opportunities Webinar Presentation

     Task 5 Charette Agenda
     Task 5 Charette Presentation

     Task 4 Kickoff Presentation
     Task 4 Results Presentation

     Task 3 Results Presentation

     Task 2 Public Webinar

     Feb 6, 2013 Meeting Presentation

     Sept. 30, 2015 Presentation
Other Southern California Basin Studies

The Los Angeles Basin Study (Study) is a partnership between the Bureau of Reclamation (Reclamation), the Los Angeles County Flood Control District (District), and several local agencies. This study is funded in part with $1 million from Reclamation’s WaterSMART program, $1.36 million from the District, and $60,000 from other local partners. The Study area covers approximately 1,900 square miles and is home to approximately 10 million people, or about one-quarter of California's population.

Imported water supplies to Los Angeles County are uncertain due to periodic droughts in northern California and the Colorado River Basin, court decisions related to Bay Delta endangered species, implementation of the terms of the Quantification Settlement Agreement for Colorado River water, and environmental concerns affecting delivery of Owens Valley water. Changing demographics and climate variability present additional long-term challenges to an adequate water supply. Various Los Angeles area water management agencies, such as the LACFCD, are actively pursuing strategies for developing local water resources such as stormwater.

The LACFCD constructs, operates, and maintains an advanced system in Los Angeles County for flood protection, water conservation, and water quality improvement, serving a jurisdiction of 85 cities and approximately 140 unincorporated communities. It owns and operates 14 major flood control dams, 155 debris basins, 27 spreading grounds, and more than 3,400 miles of channels and storm drains. It is also the primary agency for conducting groundwater replenishment operations, and in typical years, it infiltrates more than 270,000 acre-feet (AF) of captured stormwater, imported water, and recycled water into the various groundwater basins in Los Angeles County. In wetter years that number can exceed 700,000 AF, and in drier years may be little more than 150,000 AF.

Los Angeles County accounts for the largest water demand of any urbanized county in California. The purpose of this Study is to assess the region's current and projected water supply and demand, identify any gaps, and develop adaptation strategies to address impacts from climate change and population growth. The Study will also assess potential changes to the operation of the region's stormwater capture systems, modifications to existing facilities, development of new potential facilities that could help resolve projected imbalances, better manage flood control, implement improved stormwater capture practices, and or address other water supply issues. The Study will engage a stakeholder/public participation process in assessing alternatives, conducting a trade-off analysis, and highlight the region's best opportunities.  

December 2012
Begin Study
December 2013
Complete downscaled climate change &
hydrologic modeling
September 2014
Complete water supply & demand projections
August 2014
Complete existing infrastructure response & operations guidelines analysis
November 2015
Complete infrastructure & operations concepts
December 2015
Complete trade-off analysis & recommendations
Estimated February 2016
Publish final report

Send questions or comments via :

e-mail: LABasinStudy@usbr.gov
phone: (951) 695-5310
fax: (951) 695-5319

Last Updated: 9/21/17