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)
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…