Limitations in Extraction of Survey Data from Real-Time Kinematic GPS ADCP Systems

Abstract

A total of 595 real-time kinematic global positioning system (RTK-GPS) water surface elevations (WSE) were measured using georectified and nongeorectified survey systems along a 21-km-long river reach to evaluate vertical coordinate accuracy of a nongeorectified RTK-GPS acoustic Doppler current profiler (ADCP) system. A georectified survey of a series of quality control benchmarks produced a vertical root-mean-square error (RMSE) of 0.033 m, which was considered globally accurate for river survey purposes. The WSE measured simultaneously at the same locations comparing the nongeorectified to the georectified system resulted in a