Water is a Living Archive: Examining myths of where various urban streams come from: Pt. 1: Kellogg Creek
July 2, 2014 § 3 Comments
Have you ever heard rumors that water in various urban streams in Los Angeles originates in significant part from irrigation runoff?
It’s true that car wash and irrigation runoff are often seen flowing into storm drains. Dry season (summer) is the time these activities are most likely to take place. In the case of the Los Angeles River, a good deal of the river’s dry season flow comes from point source discharges rather than groundwater: one report says this figure is about 80% (Arup, 2011). Point sources include storm drains which convey irrigation runoff and carwash runoff, but also effluent from wastewater treatment plants. Flow data collected in 2000-2001 by Stein and Ackerman (2007) indicated that on the average, half of dry season flow in the Los Angeles River originated as effluent from wastewater treatment plants and half from storm drains.
As Josh Link puts it, the Los Angeles River, the end of pipe destination for a good deal of imported tap water, is effectively a « Read the rest of this entry »
March 19, 2014 § 1 Comment
I am blogging full-time over at Streetsblog L.A., so not posting much here at L.A. Creek Freak (excuses, excuses), but I thought Creek Freaks might like this article I wrote. The city of San Fernando is moving ahead on its 1.6-mile greenway along the Pacoima Wash.
Earlier Creek Freak articles about this include this intro to Pacoima Beautiful’s efforts, and this exploration of San Fernando’s 8th Street Park, which is due to open in the next couple months.
March 15, 2014 § 6 Comments
A couple weeks back, I attended the 2014 GeoDesign Summit at ESRI, in Redlands. I was incredibly inspired by examples of how GIS has been used by people in different fields from all over the country and all over the world to aid in analysis of a wide range of issues. Presentation topics ranged from urban economic development, to vegetation patterns that maximize passage of wildlife, to the layout of services in Latin American favelas.
One of the most memorable talks was the keynote address by Kong Jian Yu, founder of Turenscape.
Yu is a rock star of Landscape Architecture. Most of his firm’s work is in China. My favorite are the wetland landscapes that merge urban form with ecological esthetics. These landscapes have strong visual and experiential component but also are designed to maximize ecosystem services. Central to the provision of ecosystem services in a country where 75% of surface water is polluted, is the cleaning ability of wetlands. Other ecosystem services provided by wetlands include flood control, habitat, photosynthetic output, carbon sequestration, sediment retention and cultural and recreational value. Wetlands are only one component of “ecological infrastructure,” an infrastructure that promises to minimize management intervention while providing this wide range of benefits. Where natural wetlands have been removed, restored or constructed wetlands can still provide some of these services. This is in contrast to built infrastructure projects of the last century, typified by encasing rivers in concrete channels, which are designed to maximize one single thing: transporting stormwater quickly to the ocean.
In China, Yu advocates that ecological security is a matter of national security. Landscape planning is a matter of national defense. Ecological infrastructure must be invested in, developed and maintained.
Over thousands of years, China has struggled with devastation caused by flooding. Like in southern California, China’s flooding issues have been related to population growth, devegetation, and pressure to develop the landscape in a way that compromises its ability to provide flood control.
In his doctoral dissertation work at Harvard, Yu used GIS mapping and analysis to show that despite the country’s recurrent struggles with flooding, that flooding actually only affects 2.2% of China’s surface area. If flooding only takes up 2.2% of the land, then is it possible to simply “make friends with floods” and accept the fact of flooding? One could simply reserve these zones for flooding, develop elsewhere, and not have to worry about flood damage anymore.
Yu made it sound so simple. Though comments from the audience acknowledged the perils of the top-down style of planning that occurs in China, I was still inspired by Yu’s ideal of how ecological infrastructure can integrate science-based approaches to land management with a new esthetic that embodies ecological values.
What would an ecological esthetic look like in Southern California? Our plants and seasonal cycles are charismatic– but in a subtle way. Our esthetic might be about how shades of rust and silver transform into various shades of green after the winter rains. Or how every rainy season tells a different story, and how that story is told through the composition of wildflowers we see in the spring as well as in the way water chooses its own path through the alluvial plains. How can southern California make friends with floods?
January 29, 2014 § 7 Comments
Apologies to all our readers for putting up with very very little in the way of near material here at L.A. Creek Freak. Life circumstances took both Jessica and I out of L.A. a couple years ago. We love L.A. and her creeks and streams, but it’s difficult to keep in touch with them from afar.
I am happy to announce that I am on my way back. I’ll be returning to L.A., with my sweet wife and my 6-month old daughter, and, as of mid-February, writing full-time for L.A. Streetsblog. Streetsblog focuses on walking, bicycling, and transit issues in Southern California. When Jessica Hall and I were first starting L.A. Creek Freak, back in 2008, we discussed wanting LACF to do for water issues what LASB does for transportation issues.
I am looking forward to including a fair amount of L.A. River coverage in my Streetsblog writing. Creekfreaks may want to check out my Streetsblog article yesterday musing on how city park and transportation departments might work together better to extend L.A.’s greenway facilities including the L.A. River bike path. « Read the rest of this entry »
January 2, 2014 § 15 Comments
Over the past few weeks, I’ve been dialoguing via email with a fellow creekfreak about the location of Arroyo San Pascual, which was/is in the Pasadena/San Marino/Alhambra area. I thought I’d post the maps that explain this location so that everyone can enjoy the info. For those wishing to cut to the chase – Arroyo San Pascual is the westernmost of the creeks, joining with Mill Creek to create Mission Creek (aka, I believe, Alhambra Wash) further downstream. To the east are smaller creeks, including one that once fed the pond (Kewen Lake) that has since been filled for, um, lawn, at Lacy Park in San Marino. Jane Tsong covered the topic of the arroyos and fascinating geology of this area in depth (here 1, 2) – so I’m going to stick to the maps.
To the left, a federal survey from 1870 which actually gave us some creek names. (when I have a moment I’ll scan and post the entire survey so you can see the rest) To the right, a screen shot of the creek layer I created several years back in GIS, which when imported as kmz files in GoogleEarth has a standing flaw of being offset slightly. The discerning eye can see echoes of the historical streams in the treelines, shadows of terrain, (in)convenient siting of ball fields… correlation of course not being causation. The arrows are meant to call that out for you, imagine those blue lines shifted slightly to the left. Happy creekfreaking, if you get inspired to tour to the topography, let us know what you find out!
August 12, 2013 § 6 Comments
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.”
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.
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).
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.
July 13, 2013 § 10 Comments
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 »
May 21, 2013 § 3 Comments
Look a new post!
The good folks at Western Resource Associates, a regional nonprofit focusing on the Colorado River, have created a really cool interactive map that neatly summarizes many issues facing the once-mighty Colorado River. Check it out! Click the hyperlink (cool interactive map) or just paste this into your browser: http://coriverbasin.org/maps/
February 3, 2013 § 3 Comments
The Bronx River Alliance (BxRA) is a non-profit working to foster a healthier Bronx River. Somewhat similar to Friends of the L.A. River, they do events, education, advocacy, and work closely with communities and governmental agencies to get stuff done on the river.
I’ve worked there two days, and they’ve been great days! « Read the rest of this entry »
October 24, 2012 § 2 Comments
Hello Creekfreaks! I miss writing about LA waterways but am much enjoying the new sights and sounds of Humboldt Bay, and my new job is promising to be very rewarding. Being bay-focused, I’m reading about oysters today, and stumbled across a little anecdote I thought you might appreciate:
Native oysters grew in some of the bays in southern California, but did not form the basis of a commercial industry. Wilcox (1898, p. 647) says: “Native oysters, small in size and of little value, are found in limited quantities at several places in southern California, but are gathered only at Bolsa, Orange County. Some attempt is being made to cultivate the California oysters in the waters between San Pedro and Wilmington, where they have long been known to exist in very limited quantities.” He also stated that production in Orange County in 1895 was 25,740 pounds (probably including shells) valued at $772; at the same time the production in San Francisco Bay was 14,701,500 pounds (shell weight) valued at $538,725 (U.S. Bur. Fish. Rept., 1898, p. 651).
A decade later, in 1906, Pacific Fisherman (October 1906, p. 23) reported the native oysters in the Grand Canal at Venice, Los Angeles County, were to be exploited commercially.
-Fish Bulletin 123, The California Oyster Industry, by Elinore M. Barrett, California Department of Fish & Game, 1963