The Arroyo Seco Watershed

The Arroyo Seco watershed, stretching from the San Gabriel Mountains to downtown Los Angeles has a beauty and charm unmatched in Southern California

For many years now, Arroyo-lovers have worked hard to protect and restore our wonderful watershed. Up and down the Arroyo, citizens, neighborhood groups and governmental agencies are collaborating to manage our watershed better for nature and people and to pass on its splendor to future generations.

On this page you will be able to learn more about the Arroyo Seco watershed, its elements and the programs, organizations and agencies working to enhance it.


The Arroyo Seco Watershed Coordination Program

The Arroyo Seco Watershed Coordination program, sponsored by the Arroyo Seco Foundation, is part of a statewide effort of the California Department of Conservation funded by the CALFED Bay Delta Authority. The program is designed to improve the capacity of local residents, organizations and agencies to better manage and improve the Arroyo Seco Watershed. The key goals are to promote: water conservation, improved water quality, and community and institutional partnerships to accomplish these goals. For more information, please contact:

Watershed Coordinator


Corps Ecosystem Study Is Initiated

The Arroyo Seco Watershed Feasibility Study, a partnership between the U. S. Army Corps of Engineers and the County of Los Angeles Department of Public Works with the assistance of governmental agencies and environmental organizations within the watershed, was officially launched October 26, 2005. This was intended to be a three-year study to explore solutions for water resources, conservation, habitat and environmental restoration issues within the Arroyo Seco Watershed. Despite the strong support of local communities, the study has lagged because it has only received minimal federal funding despite the diligent efforts of Congressman Adam Schiff and Senator Dianne Feinstein.

We still have great hopes for the Corps study to provide a lot of answers regarding the sustainable management of the Arroyo Seco Watershed.

News Coverage

Study Plan


Fifteen Things You Can Do to Make a Difference in Your Watershed

Here's a handy guide to how you can learn about the Arroyo Seco Watershed, become active in watershed protection programs and help increase public awareness.

How to Make a Difference


Restoration Goals

  1. Restore the Natural Hydrological Functioning of the Watershed
  2. Better Manage, Optimize, Conserve Water Resources While Improving Water Quality
  3. Restore, Protect and Augment Habitat Quality, Quantity and Connectivity
  4. Improve Recreational Opportunities and Enhance Open Space

For an in-depth look at local water usage and issues, check these two key documents:

Watershed Budget
Water Issues


The Most Celebrated Canyon in Southern California

The scenic Arroyo Seco begins high in the San Gabriel Mountains and flows through the communities of La Canada Flintridge, Altadena, Pasadena, South Pasadena and Northeast Los Angeles to meet the Los Angeles River just north of downtown Los Angeles.


The Arroyo combines the elements of a rough mountain watershed with an urbanized streamzone surrounded by half a million diverse residents. Home to Jet Propulsion Laboratory, the Rose Bowl, Southwest Museum and dozens of other features, the Arroyo is an environmental, cultural, and recreational oasis for all of Southern California.

What Is a Watershed?

A watershed is that area of land, a bounded hydrologic system, within which all living things are inextricably linked by their common water course and where, as humans settled, simple logic demanded that they become part of a community.
- John Wesley Powell