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.

Upcoming Hahamongna Meetings

November 27, 2013—Now that the County's so-called community meetings are over, the focus on Hahamongna shifts to the local cities that will bear the brunt of negative impacts.

A series of meetings is coming up soon that will be critical in informing the community and local officials about the devasting impacts of LA County Flood Control District's plant to scrape sediment and habitat from Hahamongna Watershed Park and leave a permanent denuded zone of up to 120 acres where there is now rich riparian habitat. The traffic, noise, air pollution and environmental destruction will be horrendous.

December 2,  6:00 pm

La Cañada City Council

December 9,  6:30 pm

County Flood Presentation to Pasadena City Council

December 10, 7:00 pm

Council of Arroyo Seco Organizations Special Hahamongna Meeting

December 16, 6:30 pm

Pasadena City Coucil Will Adopt Position on Hahamongna Sediment

Make Your Voice Heard - Save Hahamongna!