Arroyo Seco Foundation

Please Support the Lawsuit to Save Hahamongna!

We're going to need broad-based grassroots support if we are going to defeat the County Flood Control District's horrendous plan for Hahamongna and our neighborhoods. We've crafted a crowd-funding campaign to support the lawsuit to Save Hahamongna. There is a great short movie and some nifty prizes for contributors. Please give generously. And share this information with your friends, associates and social media to help spread the word.

We're fighting to save the most environmentally special place in our region. Don't let it be destroyed.

Support the Lawsuit

Save Hahamongna, PO Box 91622, Pasadena, CA 91109-1622

The Trucks Are Coming! 50,000 a Year!

County Releases Devastating Hahamongna Sediment Trucking Plan

LA County Flood Control District's sediment removal program for Devil's Gate Dam in Hahamongna Watershed Park is deeply flawed. It's an old-style mining and trucking operation with devastating impacts on the nature and character of Hahamongna Watershed Park and on the surrounding communities.

Canyon Project Environmental Documents Approved; Appeal Filed

The environmental documents for the Arroyo Seco Canyon Project (ASCP) have now been approved the Pasadena Hearing Officer Paul Novak in a public hearing on January 7, 2014, moving the project to the implementation phase.

The Canyon Project is an innovative program to improve water resources and environmental conditions in the Arroyo co-sponsored by the Arroyo Seco Foundation and Pasadena Water & Power Department.


Arroyo Seco Excised from San Gabriel Mountains National Monument

By a mysterious process that no one will explain, the Arroyo Seco and the southwest corner of the Angeles National Forest were eliminated at the last minute from the newly announced San Gabriel Mountains National Monument.


Introducing Stewards of Public Land

More Exclusive Use in the Lower Arroyo? No Way!

For many months now the Pasadena City Council and staff have been considering an agreement to permanently prohibit walking, jogging, dog-walking, birding and other forms of enjoyment of nature on the west side of the Lower Arroyo in Pasadena. The area will be exclusively reserved for archers.

The same people who generated the strong community response to the proposed Lower Arroyo tree removal have formed a new organization, Stewards of Public Land, dedicated to protecting and preserving parks and open spaces in the Arroyo Seco for the public.

ASF urges you to visit the Steward's website for more details. And sign their very worthy petition while you're at it.

Sign the Petition

Help Protect Arroyo Woodlands!

It's a little beetle that could have a devastating impact in the Arroyo Seco and in local communities. The polyphagous shot hole borer (PSHB) burrows into numerous tree species and spreads a poisonous fungus.

The Arroyo Seco Foundation is looking for dedicated volunteers to survey trees for PSHB infestation in Pasadena's Arroyo Seco parks. With your help, we can determine the extent of its local presence and stop it before it spreads to the rest of our woodlands.

Contact Scott Cher at (323) 405-7326 or to sign up!

Learn more about the polyphagous shot hole borer here.


Steelhead in the Arroyo in New Exhibit and Book

The fascinating story of steelhead in the Arroyo Seco is featured in a new book, "Against the Currents," published by the Aquarium of the Pacific in Long Beach. John G. Tomlinson, Jr., tells the story of Charles Holder of Valley Hunt Club fame and his depictions of this spectacular fish and how it used to frolic in the Arroyo Seco stream. The Aquarium of the Pacific has also installed a permanent exhibit on the steelhead in Southern California as part of their watershed exhibit.


Lower Arroyo Trees Saved

Over 400 people signed our recent petition to save four native trees in Lower Arroyo Park that were slated to removed. The space occupied by three coast live oaks and a California sycamore would have been used to expand fly casting programming. The strong and prompt community action was another demonstration of the strong support for protecting and preserving the natural character of the Arroyo.

You can view the petition and community responses here.

The Successful Petition | ASF Letter to City Manager Beck

We Salute Mayor Garcetti and a United Community

Last Fall the Arroyo Seco Foundation and more than a dozen community organizations united together at the LA River Rally in support of Alternative 20, the most ambitious proposal of the US Army Corps of Engineers' ARBOR Plan to restore the Los Angeles River.

It didn't look very hopeful. The national office of the Corps seemed intent on going with a more modest proposal, but united community support and Mayor Garcetti's dynamic leadership turned the tide.

On May 28, 2014 the Corps announced that they will back Alt 20. It's a tremendous victory for the future of the Los Angeles River.

Coverage: LA Times  |  KCET  |  LAist

Pasadena Council Adopts Sediment Recommendations

On Monday, May 12, the Pasadena City Council adopted the recommendations of the Devil's Gate Sediment Working Group. This group was established by Pasadena to develop a more sustainable alternative to those presented in the LA County Flood Control District's Draft Environmental Impact Report on the Devil's Gate Sediment Removal and Management Project.

The Pasadena Sediment Plan would substantially reduce the scope and negative impacts of the Flood Control District's program, while protecting the neighborhoods and rare environmental values of Hahamongna Watershed Park and the Arroyo Seco.

Recommendations of the Sediment Working Group
Council Agenda Report
Sediment Working Group Slides

Exceptional Drought Highlights Need for Water Conservation

Western U.S. Drought Map With "exceptional drought" declared in part of the state, the first ever zero allocation of water from the State Water Project, and numerous fires, we want to remind Southern Califorians that there are many ways that all of us can do our share to conserve water. It may be as small as fixing a leak or as large as installing a drought-tolerant garden.

Here's Something Real You Can Do About the Drought - Click Here:

Arroyo Seco Canyon Project

Arroyo Seco Canyon ProkectThe Final Conceptual Design Report for the Arroyo Seco Canyon Project is now available for public review! Thanks to all those who participated in the workshops and sent in comments. ASF, the City of Pasadena, and Carollo Engineers worked hard to incorporate public input as much as possible. The result, we hope, is a project that will not only integrate water resources, habitat, and recreation but will also satisfy the needs and desires of the community.

While there is no formal public comment period for this stage in the design, please feel free to direct any questions, comments, or concerns to Rebecca Shields Moose ( and Gary Takara (