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More than 5300 Have!

Hahamongna is that rare spot in the Arroyo Seco at the foot of the San Gabriel Mountains where the mountainous watershed meets the urban plain. Periodically floods roar into this basin. Bounded on the north by the mountains and Jet Propulsion Laboratory and on the south by Devil's Gate Dam, Hahamongna contains five unique habitat zones that only exist in alluvial canyons near the mountains. Most sites like this in Southern California have been destroyed.

Don't let Hahamongna go the way of other lost environmental treasures in Southern California.

The Meaning of Hahamongna

The original settlers of the region were sometimes called the Hahamongna Indians. The word means "Flowing Waters, Fruitful Valley" in the native Tongva language.

Threats to Hahamongna

It's the most precious enviromental zone in our region, but it's under attack again.

A massive sediment and habitat removal program of the County of Los Angeles threatens to strip the basin of its rare riparian and alluvial scrub habitat

The Sustainable Plan for Hahamongna

Dangers of Diesel


A Strategy to Save Hahamongna


Hahamongna Updates

Sup Barger: "There Was An Error That Was Done"

Read the Exchange With Dorothy Wong at Supervisor's Meeting

Hahamongna — What's Next?

Report from the Arroyo Seco Quarterly Meeting

Headline: "Anger, Frustration Over 'Decimation' of Hahamongna as Arroyo Seco Advocates Convene"
Pasadena Now Reports

County Bulldozers Destroy Most Precious Habitat in Region

Come to Hahamongna —
Before LA County Totally Destroys It

The bulldozers and trucks are lined up like an invasing army ready to waste $100 million of taxpayer funds to destroy the most precious habitat and wildlife corridor in the west San Gabriel Valley.

Come discover the magic of Hahamongna before the County's trucks and bulldozers destroy it permanently.

The Big Dig Begins

The County Department of Public Works has begun its devastation. The signs are posted. They are closing trails and preparing roads down into the Hahamongna basin. They intend to strip out 70 acres of prime habitat between now and next April. Then the big sediment excavation will begin and continue for the next four years.

But don't be surprised by any delays. They been delaying their maintenance responsibility for the last 24 years, but now they can do the Big Dig. It's more fun for the engineers to create massive destruction than to perform routine maintenance.

Get ready for Hell in Hahamongna.

The Trucks Are Coming - 425 Diesel-Spewing Monsters

To Dig a Massive Pit in Hahamogna Watershed Park

Petition Climbs Past 4000: It's Still the Big Dig — Save Hahamongna

Did we go to a different meeting of the Supervisors last November or what? We thought they reduced the size and impacts of the Flood Control District's Big Dig project by at least 30%, but that's not way the Flood Control District is acting. They now intend to build roads into basin in November and to destroy more than 70 acres of precious riparian habitat early next year.

We urge all who understand the value of Hahamongna and love it to sign the new petition now.

Corps Responds: Don't Bother Us

The US Army Corps of Engineers, among its other responsibilities, is charged with protecting the precious wetlands and streamzones in the United States, including Hahamongna. Recently the Corps issued a public notice regarding their permit for the Devil's Gate Sediment Mining and Trucking program, aka the Big Dig, and gave the public the opportunity to comment on the notice. Dozens of people and agencies responded with thoughtful commments. Most requested that the Corps conduct a public hearing to discuss their responsibilities.

David J. Castanon. the Chief of the Regulatory Division, Los Angeles District, U.S. Army Corps of EngineersCorps Regulatory Division has now officially responded with a generic letter to "Public Notice Comenters." "The issues you raised are similar to these other written comments we received for the proposed project. Considering the above opportunities the public has had to submit comments to the Corps, it is unlikely any new information would be disclosed as the result of a public hearing."

He continues: "After careful consideration of your request pursuant to Corps regulations at 33 CFR Part 327, we have determined that a public hearing is not warranted at this time."

Can you hear the County's bulldozers reving up their engines?


It's Still the Big Dig!

In November the County Supervisors reduced the amount of soil and habitat to be excavated and trucked out of Hahamongna by 30%. Then in December Judge Chalfant approved the impact report for the Big Dig. But there are still tremendous problems with the Flood Control District's devastating program. Like the 400+ diesel trucks and the massive permanent destruction zone.

ASF and Pasadena Audubon offered to settle our lawsuit with the Flood Control District if they minimize the impacts on Hahamongna and the local neighborhoods accordingly. Sadly the Flood Control District has responded negatively to our settlement offer.

We want all our supporters and friends to know that our attorneys have now appealed the original court decision as well as filed a second lawsuit to ensure that the Flood Control District reduces the negative impacts of their Big Dig.

We need your continuing support to win this historic fight to Save Hahamongna and preserve the Arroyo Seco as a wonderful natural resource for future generations.

Support the Lawsuit

Supervisors Scale Back Big Dig at Hahamongna

Surprise Amendment by Supervisor Barger dramatically reduces the size and negative impacts of Flood Control's Big Dig.

November 8, 2017 — The LA County Board of Supervisors by a unanimous vote yesterday substanially modified and reduced the Flood Control District's Big Dig program for Hahamongna Watershed Park.

Besides reducing the size and negative impacts of the program, there were additional commitments made to support ecosystem restoration and water conservation in the Arroyo Seco. The vote represents a significant step forward toward Saving Hahamongna.


Thanks, Supervisors, For Showing That Hahamongna is Important to You

Hahamongna's Fate: It's Up to You . . . and the County Supervisors

County Flood Issues EIR Revisions

The County Flood Control District released their revisions to the Final Environmental Impact Report for their Big Dig mining and trucking operation in Hahamongna on July 24th. They have made some minor concessions, but the worst parts of their program are still there: 1) its too big; 2) too fast; and 3) too destructive to habitat, our air quality, traffic and neighborhoods.

There review period for public comments has now closed. Some excellent analysis of the defects of the EIR and its revision was submitted by agencies and concerned citizens. Now the Flood Control District has to review and respond to those comments and submit their program to the LA County Board of Supervisors for a new approval.

The ultimate decision on the fate of Hahamongna will be made by the County Board of Supervisors, which must act to certify that the entire EIR is in compliance with the California Environmental Quality Act (CEQA). This is the time for those who care about Hahamongna to speak with a loud voice telling the Supervisors to Save Hahamongna and ensure that the sediment removal program is reshaped along more sustainable and environmentally-sensitive lines.

We're Coming Down to the Final Decision —
Your Action Now is Critical:
Please Support the No Big Dig Lawsuit!

Remaining Steps to Save Hahamongna:

Factsheet  EIR Revisions  Sediment Resources  Contact Supervisors

The Trucks Are Coming! 50,000 a Year!

The Trucks are Coming!!!

150,000 double-bed, diesel belching monsters, clogging streets, creating noise, dust, pollution, destroying precious habitat and severely impacting our neighborhoods

SUPS: Time for a New Look at the Big Dig

Now that there's a new Board of Supervisors who are more progressive and environmentally oriented, it time for them to take a new look at the Flood Control District's devastating plan for Hahamongna and at the unchecked power of the Flood Control District.

Here's How You Can Help

We urgently need photographers, videographers, and observers to monitor and document LA County's devastation. If you can help, please send an email listing your skills and contact information to savehahamongna@arroyoseco.org.

Help Save Hahamongna

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Hahamongna is for the Birds

What a wonderful treasure Hahamongna is for birds and wildlife! (For people too, but that's another story). Participants in Pasadena Audubon Society's Hahamongna Bird Walk on Saturday spotted 45 unique species. The walk was led by Darren Dowell, Michael Long, Lois Brunet, Kathy Degner and others. You can read the complete report, including a listing of the species, by clicking on the link below. It's impressive.