Field characterization of gravity currents in the Chicago River, Illinois, USA

GARCÍA, C.M.; JACKSON, P.R; OBERG, K.,; JOHNSON K.,; GARCÍA M.H.

Lake Placid, New York, USA.

Conferencia; Hydraulic Measurements and Experimental Methods Conference; 2007

Environmental and Water Resources Institute of ASCE (EWRI) y International Association of Hydraulic Engineering and Research (IAHR)

During the winter months, the Chicago River in Chicago, Illinois, USA, is subject to bidirectionalflows, and gravity currents are thought to be responsible for such flowbehavior. The occurrence, frequency, and evolution of gravity currents in the ChicagoRiver have been described using a unique set of field observations made using anupward-looking acoustic Doppler current profiler (ADCP) during the period November20, 2003 to February 1, 2004. Detailed field observations performed on December 2005,based on both ADCP and water-quality measurements, are employed to validatehypotheses about the characteristics of the currents and the source of the denser water.Observations indicate bi-directional flow is a common condition in the Chicago Riversystem, and that density differences driving the gravity currents are mostly due tosalinity differences between the North Branch and the main stem of the Chicago River,whereas temperature differences do not seem to affect the creation of gravity currents.