The role of engineering river systems toward human aims and the consequences this has on multiple scales is the key concern of this seminar.

Human interventions into alluvial flow patterns change the form and path of rivers across the world. This seminar examines the role of engineering river systems toward human aims and the consequences this has on interdependent metabolisms at multiple scales, between the watershed, the city, and the microbe/organism.

The Mississippi River Delta is a poster child for the effects of path dependency. Its current geologic form is roughly 7000 years old, a direct result of the fan-like motion of alluvial deposits as the river changes course approximately every 1000 years. While this trajectory—or necessary path—constitutes the general topology of river-dominated deltas, the Mississippi River Delta stands out as both an emblematic and unique expression of how these alluvial formations come to pass. This is in part due to hydrological regulations mandated by the U.S. Congress, which have turned the river into a highly engineered conduit for drainage and navigation. This political decision to maintain the current path of the river by the “levees only policy” attempts to legislate the persistence of the “Third Coast”: the Port of Louisiana including the cities of Baton Rouge and New Orleans. Since these ideas took hold in 1963, a complex of structures known as Old River Control has set the flow of water between the Mississippi and the Atchafalaya, overriding the Mississippi’s intrinsic geomorphological trajectory. For this reason, the Mississippi River has turned from a vivid example of sublime nature exceeding human comprehension and influence, to the contemporary sublime and awe towards modern regulatory regimes and the incomprehensible accounts of loss should those regimes fail. How long can this societal path dependency endure, imposing control and order over the river’s trajectory, which eventually has to change course again?

This seminar explores different implications of these alluvial pathways and their relationship to the hydrological engineering that orients it today, by visiting the Bonnet Carré Spillway and the New Orleans Carrollton Water Purification Plant. The Bonnet Carré Spillway is an ideal site for understanding the relationship between engineered and naturally occurring flows because it is designed to mimic the principle of episodic breaches by creating a site for such a breach to occur, in a controlled, mechanized fashion. As infrastructure, it rests between natural and engineered operations. Carrollton Water Plant supports deeper understanding of path dependency at the scale of cities and urban systems. It is a site that uses multi-stage engineering to draw from the Mississippi and create potable water for the city. Its importance and vulnerability, however, demonstrate the need to rethink how this infrastructure operates.

Using a multi-scalar approach—with the flow of water and pollutants as connecting threads—participants will investigate metabolisms at three different scales (species, urban, deltaic). Participants will collect samples, study various components of riverine infrastructure, create collective maps and sectional drawings, and explore the dynamic relationship engineering and ecology have with path dependency. Participants will work directly with experts with backgrounds in water management, planning and design, social work, and coastal sciences to orient additional readings of the sites with concern to public access to clean water. Drawing on their experiences in the field, participants will develop possible scenarios imagining a “radical” shift in the river course and its relationship to the New Orleans area.