ALLUVIUM




Death Valley National Park, situated in the Mojave Desert, in the United States, is a place of extreme conditions. It has the highest temperature at 134° Fahrenheit, and the lowest altitude at -282 feet below sea level, to be recorded in North America. It is also a place with an intrinsic and unusual relationship with water. Badwater Basin, the site of this film’s scenes, receives only 1.5 inches of rainfall annually, also registering it as North America’s driest place. In spite of this scarcity, the landscape has a strong and tangible interrelation with water, both in the present and across millennia.




The scenes in Alluvium took their starting point from the research of Dr Noah Snyder and Lisa Kammer’s research paper Dynamic adjustments in channel width in response to a forced diversion: Gower Gulch, Death Valley National Park, California, published in the February 2008 edition of the journal Geology. Gower Gulch is a 1941 diversion of a desert wash that uncovers an expedited view of geological changes that would otherwise have taken thousands of years to unfold, but have evolved at this site in several decades due to the strength of the flash floods and the conditions of the terrain.

“Our contribution focuses on changes in width in response to a dramatic change in discharge and sediment flux in a desert river, caused by a forced diversion. This anthropogenic alteration provides a rare opportunity to investigate the transient response of a system with known initial conditions, and a large signal due to a two-order- of-magnitude change in drainage area resulting in rapid rates of channel change—a situation analogous to a step-function change in climate.” ¹

Gower Gulch provides an unique opportunity to see how a river responds to an extreme change in rates of water and sediment flow. At the time of the diversion, its drainage area was suddenly increased from 5 km2 to 440 km2 ², and the teams research uncovered that the channel had consequently widened by 33 feet on average, or 66 percent ³, thus presenting effects that could mimic the impact of climate change on river flooding and discharge. The wash was originally diverted to prevent further flooding and damage to a village downstream; today it presents us with a microcosm of geological activity.




Alluvium’s scenes are a hybrid composition of film and digitally produced simulations. Using the technique of camera-matching, the work visualizes the phenomena of water and its geomorphological consequence, beyond human scale perception. The water flow in Gower Gulch can otherwise only be perceived through the evidence of erosion and deposition of sediment. The particle animation was developed using accurate topographic models to simulate the discharge of water over a large period of time. Alluvium compresses this timeframe, providing a sense of a geological scale of time.

The work maps the velocity of the particles to their coloration, to visualize the flow and turbulence that are characteristic of fluid dynamics. The graphic technique is intended to evidence the water movement’s vector, articulating the force and directionality that have aggregated the morphology of the eroded terrain. The water data has been digitally simulated, allowing the engine to produce millions of particles that both speculate on the past events of flash flooding at the site, and also envision the phenomenon that is still taking place today.




¹ Snyder, N.P., and Kammer, L.L.*, “Dynamic adjustments in channel width in response to a forced diversion: Gower Gulch, Death Valley National Park, California”, Geology, 2008, v. 36, p. 187-190

² Schultz, L.L., “Investigation of the transient response of Gower Gulch to forced diversion, Death Valley, California” (Masters Thesis), Boston College, 2005

³ Berdik, C., “Fast Forward: Watching The River Flow”, Boston College Magazine, Spring, 2008. Accessed August 31st, 2014, http://bcm.bc.edu/issues/spring_2008/inquiring_minds/fast-forward.html