Urban Earth
Investigating the Effect of the City on the Earth and the Earth on the City



This span of the interchange linking the Antelope Valley Freeway and Interstate 5 between San Fernando and Newhall failed during strong shaking in the 1994 Northridge Earthquake. Photo courtesy of J. Dewey, USGS.At the 2001 California Biodiversity Council meeting at the Los Angeles River Center, the idea of USGS Urban Earth began to materialize. Urban Earth is a scientific initiative, or agency focus, that the U.S. Geological Survey (USGS) has deemed worthy of pursuing. If there is a muse for earth science initiatives, like Urban Earth, then perhaps the River Center was one. After all, the River Center is located near the confluence of two interesting rivers, the Arroyo Seco and the Los Angeles; some scary earthquake faults; a maze of freeways; a couple of aquifer systems; several biological corridors; and millions of people with a tremendous need to know how the changing Earth might effect them—and how they might effect the Earth. This is all great stuff to an earth scientist.

To pay homage to the muse, the first scientific proposal of USGS Urban Earth was to help with the Santa Monica Mountains Conservancy to better understand the confluence of the Arroyo Seco and Los Angeles Rivers, both near the River Center. The Conservancy wants to create a park there, perhaps by placing a rubber dam downstream and filling the confluence with water. Perhaps not. “What can be done and what are the consequences?” The questions are numerous and involve water quality, floods, groundwater plumes, earthquake faults, liquefaction, and biological habitats to name a few.

These are all questions the USGS Urban Earth was built to answer. By drilling a core sample here, taking a water sample there, and counting some critters under there, you have not only answered some pressing questions for the Conservancy, but you have also contributed to the overall body of scientific knowledge needed by everyone else.

An abandoned shopping cart sits in the concrete channel of the Los Angeles River near the confluence of the Arroyo Seco River. Photo by Dale A. Cox, USGS.

The purpose of USGS Urban Earth is to combine the knowledge of geology, hydrology, geography, and biology to investigate the effect of the city on the Earth and the Earth on the city. It hasn’t been done before—at least not by this federal agency. Earthquakes, floods, water shortages, water pollution, fires, invasive species, landslides, debris flows, and stresses on biological habitats make southern California the nation’s second largest metropolitan area, with one of the highest risks from natural hazards. USGS Urban Earth is attempting to capitalize on areas of shared expertise, within the USGS and with local cooperators like the Santa Monica Mountains Conservancy, to discover overlapping goals. Urban Earth seeks to find the causes and consequences of earthquakes, better management techniques for water resources, and the knowledge to help restore riparian and coastal habitats, and maybe, float a kayak in a city park. This research is of every day value to the 20 million people of southern California and critical to the governments, industries, and people of the region.

Hats off to the CBC for bringing the USGS to this important and interesting confluence in its history.


Dale A. Cox is a coordinator and instigator of Urban Earth. He handles Public Affairs for the USGS in California.



# # #





California Biodiversity News: Volume 10, Number 1
Spring/Summer 2003
For more information on the California Biodiversity Council, please contact:
Erin Klaesius, Communications Coordinator
CA Biodiversity Council
1416 Ninth Street, Suite 1311
Sacramento, CA 95814

Email: erin.klaesius@fire.ca.gov