A computer-aided approach for adapting stage-discharge ratings and characterizing uncertainties of streamflow data with discrete measurements

First posted September 28, 2022 For additional information, contact: Director, Upper Midwest Water Science CenterU.S. Geological Survey1 Gifford Pinchot DriveMadison, WI 53726Contact Pubs Warehouse Relations between stage (water level) and discharge of streamflow through a natural channel are the result time-varying processes, which commonly described by stage-discharge ratings. Hydrographers with U.S. Survey successfully maintain accuracy data manually applying time-tested approaches to adapt ratings temporal changes in hydraulic conditions. The difficulty manual approach is that it subjective, time-consuming process requires considerable skill experience implement. In addition, adjustments make quantification resulting uncertainties problematic. A computer-aided adaptive estimation proposed track sequential relation at continuous-record streamgages. this report, adaptations based strictly on discrete measurement then used compute magnitudes streamflow. entails parameterization cubic regression spline (CRS) for an existing rating or set measurements. state-space model parameterized relations beginning initial CRS using Finally, Kalman estimate magnitude uncertainty flows. case study from streamgage 04122500 Marquette River Scottville, Michigan, five-parameter was estimated provide parameter model. parameters were updated sequentially periodic measurements spanned 30-year period analysis. Additional analysis needed determine timing rapidly varying shifts more precisely than relatively infrequent currently enabled. Unit estimates flow local streamgaging network may basis adapting unit time intervals augmenting within