Resources for armchair creek freaks
May 18, 2016 § 1 Comment
When this blog first started, those of us interested in what our neighborhoods used to look like in the far past had to trek to libraries and archives all over town to find old maps, then figure out a way to photograph or scan the most useful. To understand how these maps related to the contemporary landscape, I used to superimpose scans of old maps over contemporary ones by using Adobe software- a slow, cumbersome, and inaccurate process!
Since then, there has been an explosion in the quality and quantity of map resources online. Best of all, some have already been georeferenced (digitally located in physical space), which means that anyone can very casually compare any neighborhood now to what it was 100 years ago by using a slider.
Here are some of my favorite places to look for old maps of Los Angeles:
USGS Historical Topographic Map Explorer (click on the area of the US that you want to view, then choose a USGS map from the timeline to view)
William Hammond Hall’s irrigation maps at the David Rumsey Map Collection (some of the LA area maps have been georeferenced, but if you have the interest, anyone can contribute by georeferencing new ones….such as the one of San Bernardino pictured below)
Ballona Historical Ecology (Ballona Creek only)
Here is a modest effort of my own from way back, a synthesis of William Hammond Hall’s sketch of the North Branch of the Arroyo Seco with elevation data of the same area created in ArcGIS, then shared through the old Google Maps interface. It was a disappointment that the shared map was not readable with a phone due to the quirky layout of the old Google Maps interface… but when I have time maybe I’ll start playing with some of the new map-customization tools online…
I am fascinated by the messiness of the historical landscape before it was flattened and filled, with water confined to neatly linear paths. There are so many notations mapmakers used to depict the ways water manifested in the historical landscape. William Hammond Hall’s maps go beyond mere notation, into the realm of artistic representation. In contrast, USGS maps of contemporary Los Angeles use a limited and inflexible set of icons to depict water: blue lines for waterways (thin or thick, solid or dashed), and blue amoebas for lakes. Does the simplicity of these icons reflect what we’ve done to our surface water; or has what we’ve done to our surface water reflect our simplistic cultural idea about how a water body is supposed to look like and behave?
Early aerial photos are another great resource for armchair creekfreaking. UCSB’s collection of aerial photography, which spans the last century, is now easier than ever to access online. Just zoom in to an area that you would like to see, then select an area to browse aerial photos in the collection. Look for photographs taken before the great stormwater engineering projects of the midcentury.
Let us know of other good resources you know, or any wish-list map projects to consider in the comments section…. there is another great map viewer in development that visualizes percolation, alluvial geology, water quality, and other topics, whose link I’ll post very soon…
Ballona’s historical ecology – and new awesome map site
January 23, 2012 § 7 Comments
As many of you probably already heard, last week the Coastal Conservancy approved up to $6.5 million to complete studies and permitting for the Ballona Wetlands. If that price tag for planning is giving you sticker shock, I have two words: Army Corps. Actually more than two words – you see, one alternative proposes removing and relocating the levees that currently contain Ballona Creek’s flows from spreading over the wetlands. (You know, the way in undisturbed situations fresh water from a stream or river normally spreads over wetlands, making the land, you know, wet.) And removing and relocating levees is sensitive business, and an involved regulatory process that has to be paid for and that can rapidly add up to a big chunk of the $6.5m.
That’s just the regulatory/cost barrier. Some people are concerned about the potential flood risk to humans, while others are concerned about the flood risk to…the wetlands. This has been an ongoing debate, and while it’s not the point of today’s post, I think we’ve got new information that can help us all consider the alternatives – as well as create new projects. Back when I was watershed coordinator, I felt the conversation about the watersheds could be elevated if we had a better handle on the historical ecology of the watershed. Agreed-upon, documented sense of what natural processes shaped the habitats of the watershed, and what had actually been here. I drafted a proposal for this study, as well as an assessment of the watershed’s springs/water budget, both of which got funded and managed by others later.
And the historical ecology report is done, and is beautiful! Props to the team comprised of CSUN, SCCWRP, SFEI and UCLA researchers! « Read the rest of this entry »
April 17, 2009 § 4 Comments
I am in the midst of a depressing exercise of stream deletion, viz. the image at right. Once again, mapping streams of LA, and then deleting them to be able to say with some reliability what’s left. It’s painstaking as well as simply painful.
While simultaneously reaching for some (legal) numbing agent and zooming in a former stream on the north slope of the Hollywood Hills on GoogleEarth, however, I noticed urban runoff dribbling down the gutter. I was looking for any chance that a stream channel persisted (further down the road, there was in fact an open semi-channelized waterway – so it wasn’t entirely empty hope). Curious, I followed the runoff upstream, till I arrived at what was clearly a stream. And it is pretty apparent that the runoff is coming from the stream. The next canyon over showed a similar pattern of runoff. And it was in the month of July, so not seasonal, this.
I often find myself wondering during conversations about “urban runoff” how much of it is genuinely from some idiot watering his or her driveway. True, we have no shortage of waste from poor water management, and plenty of it is polluted.
But here is interesting evidence that some runoff is from a stream just being a stream – and that it would still be flowing in a stream if we hadn’t rammed a street through it. Suggestive to me, anyway, that we might want to have a policy for managing this urban runoff a little differently than treating it like wastewater.
LA Streams in early 1900
August 2, 2008 § 2 Comments
Los Angeles’ natural environment has obviously changed a great deal with its history. So much so that it is difficult for ecologists and historians to re-create a picture of LA before 1860. By 1900, a lot had happened to this region – lands that had been managed by the Tongva had been converted to ranching and grazing lands under the Spanish and later Mexican colonies, and subsequently farmed fairly intensively by Anglo-American settlers (a troublesome term, I mean Anglo in the way my hispano ancestors did, coming from the word anglosajón, English speaker). These landscape changes may seem subtle to our urbanized eyes, but they resulted in significant changes of habitat & vegetation, runoff & groundwater infiltration patterns, and water use (widespread pumping of the groundwater). So the streams noted in 1900 were mostly likely quite different in 1800. And we know that urbanization has resulted in even more dramatic landscape changes.
As Joe’s post noted, Blake Gumprecht’s the Los Angeles River: It’s Life, Death, and Possible Rebirth is an excellent description of the river, based on first hand accounts, and its demise into its current state. One source Gumprecht mentions in his book is a flood control engineer, James P. Reagan, who in 1914 interviewed old timers for their memories of floods and waters in LA. A colleague handed me a photocopy of Reagan’s interviews several years ago, and my sense of LA has never been the same. Here’s a juicy tidbit describing the Carson-Dominguez-Compton-Gardena area (more of these to follow as time for typing allows):
The Carson Brothers at Dominguez have lived there all their lives. Ed. Carson states that the river at one time ran along the foot of the hills at the Dominguez home place, 1824. They said that from Dominguez hill to Los Cerritos is considered the river. In 1858, perhaps it was the ’60-’61 flood, a boat came up from San Pedro and took the Carson family, who lived over in the valley east of the Dominguez home, off of their marooned and dangerous position and carried them over to the Dominguez place.
The floods in those days were not so damaging and did not wash as they do in these later days, for there were no railroad embankments to hold the water or to concentrate it, but the water was free to spread out over the valley and did little damage. And too, the valley was covered with a growth of willow, larch, and sycamore trees, together with grasses and other undergrowth which prevented a rapid movement of waters. The railroad fill from what is now Elftman and Watson, was washed out and the floods poured into the…Slough. This was 1889. About 1894 the Slough began drying up rapidly, and fish began to die by the tons. The stench became so bad it became necessary to burn and burn the dead fish. This greatly fertilized the land….
One excellent recent account detailing landscape changes with respect to our waterways is the study, Historical Ecology and Landscape Change in the San Gabriel River and Floodplain (careful! clicking on this link unleashes a 16.5 MB download but well worth the read!), put together by a great team of researchers out of Southern California Coastal Waters Research Project (SCCWRP), Cal State Northridge (CSUN), University of Southern California (USC), San Francisco Estuary Institute (SFEI), and the Los Angeles and San Gabriel Rivers Watershed Council (LASGRWC). The project was funded by the Rivers and Mountains Conservancy (RMC). While we obviously can’t reclaim the landscape of 200 years ago, or even 100 years ago, we can recover some of our natural environment. More on that later.