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Arroyo Seco Foundation

News of the Arroyo


Finding the hidden waterways of Los Angeles County, starting with the Arroyo Seco





<b>March 4, 2017</b> - Steve Scauzillo explores Hahamongna and its wonders. He laments the fact that a recent Pasadena candidates' forum neglected our region's most important environmental treasure.<b></b> -


Steve Scauzillo


Pasadena Star-News


Walkers head into Pasadena’s Lower Arroyo Seco. This week starts off with sunshine but will turn to more rain at the end of the week. Sarah Reingewirtz/Staff Photographer

I found the Arroyo Seco with my two feet. Or, shall I say, it found me.

The sound of mud sucking up around my faux leather shoes was a dead giveaway. Not to mention the frigid creek water seeping through my pant legs. Yup, I can check it off the list! Another hidden waterway of Los Angles County found.

There are too many hidden creeks, streams, marshes and waterfalls in the county or a short hike away into the Angeles National Forest to name in this limited space, so forgive me for being incomplete.

What I’ve discovered after nearly 30 years of covering the environment is that too many of these gems remain unknown to most people. Those with way-finding signs — Chantry Flat’s hiking trails with Sturtevant Falls and Hermit Falls; Eaton Canyon Falls (which I wrote about Feb. 19 in this space), the San Gabriel River and the Los Angeles River — get a lot of attention and draw large weekend crowds.

But the signs, exits and directions to many of the places are often sparse, poor, or non-existent, too. An internet revolution has informed people where to go, even if the U.S. Forest Service, Caltrans, counties and cities have not.

There are no signs on the 210 or 134 freeways for Hahamongna Watershed Park or the Arroyo Seco. Just so you know, take the 210 West and exit at Oak Grove Avenue, turn right, then take a left on Oak Grove; opposite La Cañada High School is Hahamongna Park. Once you go in, it’s an adventure finding the trails, as I quickly learned on Friday.

A canopy of Oak trees over a group of people playing frisbee golf at Oak Grove Park. City of Pasadena contracted a tree service Thursday to cut down seven oaks trees and one Willow tree. The city had marked the trees as being diseased or in danger of falling creating a potential safety hazard. Tim Brick, Executive Director of Arroyo Seco Foundation was upset that his organization was not notified about the planned removal of the trees and question whether these trees needed to be removed. Walt Mancini/Staff Photographer

On foot, I followed the dirt fire road marked with tractor tracks to the creek, running gently with fresh water from the mountains. I hopped from rock to rock and continued toward Devil’s Gate Dam. I was surrounded on both sides by a curious marshland of 10-foot tall willow trees with green buds on their branches like buttons up a sleeve. I warn anyone to stay out of washes or rivers during a storm. I chose to see for myself what many say is the newest natural area — hidden waterway — in Pasadena.

I was ankle deep in oozing mud, part of the make-shift “natural” area growing in Hahamongna, home to rare birds, frogs, lizards and the occasional snake. A yellow-and-black monarch butterfly flitted by me. Two birds perched in a taller tree sang, alternately swooping down to catch insects.

I started walking back toward the Jet Propulsion Laboratory, finding terra firma. As I shook the caked mud off my shoes I thought to myself, “this is real.” This is nature’s re-creation. After the generous rains of the season, the live oaks took on a healthy hue (no more drought gray!) and the still water seemed to float around the taller trees, capturing leaves and flower petals on the surface. The view looked like a Monet landscape.

A California towhee ran across my path, stopping to pick at the mud for worms. I walked toward the two boulders that lay at the feet of the San Gabriel Mountains and found a firmer, higher trail. The sound of a busy woodpecker echoed his tune, an urban backbeat behind the steady din of freeway traffic.

As you may know, two environmental groups want to stop the county’s clean-out of this area of new marshland, which the county says is necessary to keep the dam working efficiently. The issue is in court, with the judge recently calling the county’s environmental mitigation plan deficient.

Whatever happens, improvements should be part of the settlement. The trails around the Arroyo Seco need better signage. The pole that had a sign leading to a trail well above the marsh had no sign affixed. A JPL scientist walking the trail said the Arroyo Seco Trail swings around the dam and leads up the canyon. I know there are not even bike paths in the Lower Arroyo Seco because I tried to ride it on my bike and my tires got stuck in the sand.

At a recent Pasadena City Council candidates forum on the topic of environment and sustainability, almost no one mentioned Hahamongna or the Arroyo Seco, two hidden waterways so close, yet so far.

Steve Scauzillo covers transportation and the environment for the Southern California News Group. He’s a recipient of the Aldo Leopold Award for Distinguished Editorial Writing from The Wilderness Society. Follow him on Twitter @stevscaz or email him at




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