Retracing the LA River: 1928-2018 Aerial Comparison

As the Los Angeles landscape transformed from scrub grasslands to open grazing, from fruit orchards to residential neighborhoods, the path and look of the LA River has changed with it.

Juxtaposing Google Earth imagery from 2018 with historical vertical aerial photography from 1928, this animation traces the 51 mile LA River revealing its past and present conditions and setting the stage for potential futures. Beginning at the confluence of Bell Creek and Arroyo Calabasas in the City of Los Angeles’ Canoga Park neighborhood, follow the river to Long Beach where it meets the Pacific Ocean.

The 1928 imagery, accessed from the UC Santa Barbara's Library FrameFinder database,  provides the oldest complete aerial survey available of the LA River, capturing it in a time of radical transition. Historically, the river had always been both periodically dry and, at times, prone to severe flooding, as seasonal natural disturbances caused water to rush out of the San Gabriel Mountains and spill out across the wide alluvial Los Angeles Plain. By 1928, the river’s use for irrigation had attracted agriculture and settlement and the subdivision of land and construction of gridded streets was already apparent. In the following decade, increasing encroachment and flood damage led to the river’s nearly complete channelization, locking it into its current concrete alignment. Today over one million people live within a mile of this iconic piece of flood-control infrastructure. 

The 2018 aerial animation was created using Google Earth Pro and its default Landsat / Copernicus imagery and Google Earth’s Movie Maker. The 1928 aerial animation was created using Fairchild Aerial Surveys Flight C-300 historical vertical aerial photos, taken between December 31, 1928 and January 1 1928, scanned in 2015, and now available through UC Santa Barbara's Library Frame Finder. Aerials within 1-2 miles of the LA River were selected, downloaded, arranged and warped in Photoshop to align to a street grid as a guide, and then photo-corrected for consistent contrast. Finally after the images were merged together in Photoshop, the new mosaic image was imported into ArcGIS, geo-referenced, and imported into Google Earth Pro for animating with the Google Earth Movie Maker tool. Finally, the two animations were combined and finished in Adobe After Effects.

This animation was created in parallel with OLIN’s work on various LA River projects, including the LA River Master Plan, and was produced by Nate Wooten and Diana Jih with the support of OLIN’s Tech Lab. OLIN’s LA River Masterplan project was featured in the University of Pennsylvania’s Ian L. McHarg Center’s Design With Nature Now exhibition and book in 2019.

Resources:

2018 - Google Earth, Image Landsat / Copernicus

1928 - UC Santa Barbara Library FrameFinder, Fairchild Aerial Surveys Flight C-300 - Imagery acquired from Teledyne Inc., 1986 and Whittier College, January 2013. Nitrate negatives scanned, 2015. Start Date: 1928-01-01 - End Date: 1928-12-31. Scale:1:18,000

http://mil.library.ucsb.edu/apcatalog/report/report.php?filed_by=C-300

http://mil.library.ucsb.edu/apcatalog/ready_ref/county.php?County=LOS%20ANGELES

https://www.news.ucsb.edu/2019/019380/bird-s-eye-time-machine