Hahamongna is the 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.


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Devil's Gate EIR Toolkit

Here you will find tools to give your information and background to help you prepare your comments for the Devil's Gate Environmental Impact Report. We will be adding additional material, so check back regularly for new resources and to view the public comments.


Devil's Gate Dam

Sediment Management

Hahamongna Watershed Park

County Environmental and Planning Documents

Bulletin Board

Post Your EIR Comments Here

EIR Comments Are Due by November 11, 2011

WAYS TO SUBMIT COMMENTS:

  • SCOPING MEETINGS - Speak at the public meetings.

  • EMAIL - reservoircleanouts@dpw.lacounty.gov (Include "Devil's Gate Reservoir Sediment Removal and Management Project" in the subject title)

  • WRITE -
    Los Angeles County Department of Public Works
    Attn: Water Resources Division - Reservoir Cleanouts
    P.O. Box 1460
    Alhambra, CA 91802-9974