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ARS Home » Midwest Area » Columbia, Missouri » Cropping Systems and Water Quality Research » Research » Publications at this Location » Publication #380301

Research Project: Long-term Management of Water Resources in the Central Mississippi River Basin

Location: Cropping Systems and Water Quality Research

Title: Comparisons of radar, bubbler, and float water levels in the Goodwater Creek Experimental Watershed

Author
item Baffaut, Claire
item Sudduth, Kenneth - Ken
item SADDLER, JOHN - Retired ARS Employee

Submitted to: Interagency Conference on Research in the Watersheds
Publication Type: Proceedings
Publication Acceptance Date: 5/3/2021
Publication Date: 5/1/2022
Citation: Baffaut, C., Sudduth, K.A., Saddler, J.E. 2023. Comparisons of radar, bubbler, and float water levels in the Goodwater Creek Experimental Watershed. In: Latimer, J.S., Bosch, D.D., Faustini, J., Lane, C.R., Trettin, C.C., editors. Enhancing Landscapes for Sustainable Intensification and Watershed Resiliency. Proceedings of the Seventh Interagency Conference on Research in the Watersheds, November 16-19, 2020, Tifton, Georgia. p. 99-109. https://doi.org/10.2737/SRS-GTR-264.
DOI: https://doi.org/10.2737/SRS-GTR-264

Interpretive Summary: Multiple means of measuring and recording stream stages ensure that a backup is available if the primary equipment fails. A common set up at ARS research facilities includes a flow bubbler and datalogger as the primary equipment and a float-driven sensor and a chart recorder as a backup. Radar based systems could be a useful primary or secondary measurement device. Multiple evaluations of radar measurement systems exist for lake or ocean tide water levels but few have been conducted for smaller streams. This paper quantifies deviations of measured water levels with a float and chart system, a bubbler, and a radar at the outlet of a 72-km2 watershed. These deviations help identify conditions for which the radar or the bubbler do not provide satisfactory data. The paper proposes a framework to quantify the uncertainty of the water level measurements, which translate into uncertainty of the measured discharge and the associated transport of water quality constituents. Measurement uncertainties help conservation managers differentiate the observed effects of conservation practices implemented in the watershed from measurement errors.

Technical Abstract: Multiple means of measuring and recording stream stages ensure that a backup is available if the primary equipment fails. A common set up at ARS research facilities includes a flow bubbler and datalogger as the primary equipment and a float-driven sensor and a chart recorder as a backup. Radar based systems could be a useful primary or secondary measurement device. Multiple evaluations of radar measurement systems exist for lake or ocean tide water levels but few have been conducted for smaller streams. The study compares water levels measured at the outlet of the 72-km2 Goodwater Creek Experimental Watershed with a radar, a flow bubbler, and a float-driven sensor. Diurnal variations caused by the radiation on the radar unit were eliminated by insulation around the radar unit. At high stages, the float and chart system produced an oscillating pattern with magnitude increasing proportionally to the stage. The differences between radar and bubbler values were also proportional to stage and could be used to quantify the uncertainty of the stage measurement. These relationships provide an automated method to quantify the uncertainty of stage measurements.