Woodman Avenue, Bicycles and Fish

February 28, 2014 § 3 Comments

Rainfall makes a creek out of the newly completed Woodman Avenue green street medians.

This morning’s rainfall makes a creek out of the newly completed Woodman Avenue green street medians.

I just posted an article at L.A. Streetsblog that wouldn’t be out of place at L.A. Creek Freak.

It’s the first part of a series where I’ll be exploring the connections between streets and creeks. I’ll be highlighting various green street projects, this article shows off the recently opened  Woodman Avenue Multi-Beneficial Stormwater Capture Project – a collaboration of The River Project and the City of Los Angeles.

Through a chainlink fence: the Arroyo Seco back and forth in time

August 12, 2013 § 5 Comments

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Fig. 1a. Looking North from Avenue 43. 2013. Hieu Nguyen. Note Southwest Museum on left and a narrowed stream channel.

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Fig. 1b. Looking North from Avenue 43. 1901-1916. Minerva Classics. Note Southwest Museum on left, and tracks in streambed used for quarrying during harbor construction.

As part of coursework for Dr. Susan Mulley’s  Research Methods seminar in the graduate program in Landscape Architecture at Cal Poly Pomona, Hieu Nguyen chose to examine landscape changes to the Arroyo Seco through the technique of repeat photography. By comparing historical photographs to contemporary views taken from the same location, Nguyen hoped to detect changes in the parkway landscape throughout the years. “I was mainly looking for vegetation changes, urban development, physical deterioration, and obstructed viewsheds.”

Nguyen had treated the Arroyo Seco in a previous Urban Planning project, and was drawn to the topic again because of “the history, design, and uniqueness of the parkway’s scenery.”

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Fig. 2a. Looking Northeast from Marmion Way. 2013. Hieu Nguyen.

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Fig. 2b. Looking Northeast from Marmion Way. 1935. Los Angeles Times.

Narrowing down available historical photographs to 10-15 that could be feasibly be physically located, Nguyen headed into the field. But things did not go quite as expected. Nguyen’s narrative offers a poignant view at how physical access to the arroyo has changed:

During the trip, I found out that I could not locate all of the camera angles that I intended to shoot due to the urban development, fencing, private properties, etc.  For one photo, the walkway was so narrow, I had to grab onto the handrail on the bridge to keep myself balanced while I was taking the photo as the cars were passing by me at 40-50 mph.

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Fig. 3a. Looking Northeast from Pasadena Avenue. 2013. Hieu Nguyen. Note deepening and narrowing of the streambed.

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Fig. 3b. Looking Northeast from Pasadena Avenue. 1955. Los Angeles Public Library. Note California sycamores lining the floodplain in the distance.

For another photo, I had to climb down the Arroyo Seco Channel to get the camera angle that I wanted.  However, I was not satisfied with the angle and wanted to take it from the other side of the shallow running water way.  So I tried to jump across, almost slipped and got myself all wet from knee down.  But when I went home and overlaid the historical photo and the current photo, I realized that the current angle was incorrect because the channel bed today was much lower than the historical one due to the flood management and channelization of the Arroyo Seco (Fig 4a).

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Fig. 4a. Looking Northeast from Avenue 26. 2013. Hieu Nguyen.

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Fig. 4b. Looking Northeast from Avenue 26. n.d. Los Angeles Public Library Herald Examiner Collection.

One of my biggest disappointments was finding a lot of chain link fences on the bridges along the parkway. Because most of my camera shots were taken from the bridges, most of the photos were obstructed by the fences (Fig. 1a). Nonetheless, my professor, Dr. Susan Mulley, and classmates all agreed that the fences were significant landscape changes to the grand viewshed of the originally designed parkway and an important part of my research analysis.

Just as starkly, the historical photographs themselves show a channel that was anything but pristine. Creek Freak co-founder Jessica Hall notes that the Arroyo Seco was once characterized as a shallow and broad river. But even the earliest of the historical photos above already show levees and other substantial encroachments onto the Arroyo’s broad floodplain, which confine flow to a narrowed and deepened channel.

Such encroachments suggest that channelization did not happen in one fell swoop– attempts to control the flow of winter stormwater dated from the beginning of development in the Los Angeles basin and intensified with the changes in stormwater flow regime wrought by devegetation and proliferation of impermeable surfaces. The Army Corp’s famous post-1938 feats of flood control are merely the culmination of this history of efforts at confinement. The final result–  a smooth and clean channel so conveniently free of vegetation or anything that might obstruct the swiftest flow of precipitation toward the sea. Gone is the disorderly seasonal dynamism of the original floodplain connecting the foothills to the coast. Channelization creates a streambed as neat as a conveniently placed pipe. One might imagine that streamflow originates from a magical tap in the foothills, rather than from the seeping of precipitation into the soil, and its slow under- and aboveground migration to the sea, which happens to leave in its wake a messy mosaic of vegetation and wildlife habitat.

Nguyen’s photographs also illustrate how armoring of banks with concrete did more than just alter hydrology and habitat. Channelization thoroughly severs any natural functional relationship between various parts of the larger watershed — literally paving the way to the radically featureless flat urban landscape we know today.

From the Society pages: Botox on the Beach?

July 13, 2013 § 10 Comments

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Broad Beach in 2012 with stone revetment wall, Google Earth

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Broad Beach in 1994 with wider beach, Google Earth

A recent article in the society pages of Vanity Fair details the woes of property owners along Broad Beach in Malibu, where the narrowing of a beach by 60 feet over the last decade has alarmed wealthy residents. Property owners built a 13-foot high stone revetment wall to protect their houses. Now, they are planning to spend $20 million out of their own pockets to import 600,000 cubic yards of sand, hoping to widen the beach by 100 feet.

Apparently even the residents understand the addition of sand (“beach nourishment”) is at best a temporary solution. To maintain the width of the artificial beach, nourishment would have to be supplemented every 5-10 years—a cosmetic solution that JPL climatologist Bill Patzert called “botoxing the beach.” (Cohan and Grigoriadis 2013)

Nor are revetment walls a real solution. Though they appear to protect property immediately behind them, they actually reflect wave energy to other parts of the coast, where erosion is then accelerated.

Some attribute the erosion of Broad Beach to winter storms. Impending  sea level rise certainly will not help.  « Read the rest of this entry »

Reflections on River Access

October 4, 2012 § 2 Comments

Sepulveda Basin: Great Blue Heron and Kayakers, Summer (painting by Joan Wolfe ©2012)

As the heat of summer slowly (hopefully) begins to wind down, so too has the second season of the pioneering L.A. River kayak and canoe excursions. The final group dropped into the River this past Sunday, an undoubtedly leisurely paddle between willows and sycamores, shopping carts and plastic bags. The 2012 installment hosted approximately 2,000 participants, an impressive increase from 2011, when the count for the pilot program was 260. The number of outfits operating on the River has also doubled and now includes Paddle the L.A. River (organized by L.A. Conservation Corps, MRCA, The River Project, FoLAR and Urban Semillas) and L.A. River Expeditions (organized by George Wolfe and the San Joaquin River Stewardship Program). I had the pleasure of paddling with both groups as a guest educator (thanks to Melanie Winter and George Wolfe for getting me out there!), a journey every Angeleno within reach of a buoyant non-motorized vessel should be able to experience at least once. « Read the rest of this entry »

This Week’s New Yorker Cover and the Future of Urban Environmentalism

August 23, 2012 § 4 Comments

Cover of New Yorker magazine 27 August 2012, artwork by Bruce McCall

This week’s New Yorker magazine cover, dated August 27th 2012, depicts a lush green Manhattan. It’s Times Square; there are tall buildings, green roofs, a waterfall, a river, grazing buffalo, a canoe, a horse, people sitting around. To me, it kind of looks kind of like paradise – a city in harmony with nature.  « Read the rest of this entry »

A(rroyo) Rosa Castilla by any other name

August 19, 2012 § 5 Comments

Alignment, Arroyo Rosa Castilla, based on 1926 and 1928 USGS Quad maps. You’re looking at over 14 miles of blueline stream.  Base image: GoogleEarth. Overlay by J.Hall.

I love to see people get creekfreaky, so it was a good day last Friday when friends posted the Eastsider’s story linking to the El Sereno Historical Society’s post on Arroyo Rosa Castilla, the creek that formerly ran along the 710 Freeway.  (Creek Freaks have long observed the propensity for Caltrans-and others-to lay major roadways in the beds of creeks – viz. Arroyo Seco/110, LA River/5 and 710 Fwys, San Gabriel River/605 Fwy, Topanga Creek and Topanga Canyon Road – and Rosa Castilla here among them).   A little sign on the freeway will tell you it is called the Sheriff’s Range Gulch. « Read the rest of this entry »

Upcoming Sediment Removal Meeting: Big Tujunga Dam

June 18, 2012 § 2 Comments

OK, thanks to Rick Grubb, I’m getting this with time for you to put it on your calendars!!

The County of LA is having a joint meeting with the USFS on sediment removal of Big Tujunga Dam.  Dirt’s all the rage here at LA Creek Freak, as you know.  Rick’s also communicated that he wants to see Arroyo Toad back in his region, one of many species that have been impacted by our flood control system.

Here’s the details:

Tuesday, July 24, 2012  6 to 8 p.m.
 
City of Los Angeles – City Council District 2
Sunland-Tujunga Field Office
7747 Foothill Blvd.
Tujunga, CA 91042 (map)
The United States Forest Service (USFS) and the County of Los Angeles Department of Public Works (DPW) will jointly present the Big Tujunga Reservoir Sediment Removal Project.  Information will be provided about the project, the National Environmental Policy Act (NEPA) and the California Environmental Quality Act (CEQA).  The public will have the opportunity to ask questions of the USFS and DPW and comment on the project.  Please plan to join us for this meeting.
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