In search of technologies for monitoring river discharge

Ralph T. Cheng, John E. Costa, F. Peter Haeni, Nick B. Melcher and Earl M. Thurman
Water Resources Division, U.S. Geological Survey, Menlo Park, California

Abstract

The US Geological Survey has the responsibility of monitoring discharge for more than 7000 of America's rivers. The present methods for determining river discharge are expensive and often require field technicians to work in hazardous conditions. Because of the importance of the streamgaging program, the US Geological Survey has launched a systematic effort in search of new technologies to alleviate the present shortcomings. A possible approach is to develop a "non-contact method" that could be used in routine river discharge monitoring by direct measurement of river cross-sectional area, water surface elevation, and water velocity distribution across the river. If the direct, non-contact approach can be proven accurate, it would reduce streamgaging costs, improve accuracy, and reduce hazards associated with traditional methods. A task committee, Hydro-21 (Hydro-21), was formed in late 1996 to provide vision and leadership at the US Geological Survey for identifying and evaluating new technologies and methods that might have potential to change the paradigm in the streamgaging program. Hydro-21 has considered a broad spectrum of techniques including acoustics, image methods, laser, and radar. At present, Hydro-21 favors radar technology for monitoring river discharge by direct measurement of open-channel properties without contacting water. To prove the concept of "non-contact discharge measurement", Hydro-21 has conducted a series of field experiments. This chapter summarizes past research activities and discusses the future direction for new technologies.

Citation: Cheng, R.T., Costa, J.E., Haeni, F.P., Melcher, N.B., and Thurman, E.M., 2002, In search of technologies for monitoring river discharge, in Younos, Tamin, ed., Advances in Water Monitoring Research, Water Resources Publication, p. 203-219.