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OSW Hydroacoustics

Summary of Minimum Requirements for Documenting Index-Velocity Ratings

This table provides a summary of the minimum requirements for documenting index-velocity ratings, as specified in USGS, Office of Surface Water Technical Memo 2015.05.
Index-Velocity Rating Documentation Electronic Data Archive or Rating Spreadsheet or Analysis Tool Station Analysis Station Description
ADVM configuration information currently in use: frequency, location in the water column, mounting information, salinity used (only required for coastal sites) measurement volume beginning and ending distance, multi-cell (number and size of cells, blanking distance), averaging period, and measurement interval Required
Measurement summary: Required fields: measurement number, date, start and stop times, stage, discharge, rated area, index velocity, measured mean velocity, brief justification (comment) for any measurements excluded from rating development, shift calculation and information if applicable; Optional fields: rated discharge, percent difference from rating, multi-cell velocity data, measurement rating, comments Required
Documentation for graphical data analysis Required
Regression analysis software output: regression statistics, regression residuals Required
Graphical documentation for regression analysis: line fit and residuals plots Required
NWIS Rating #, summary of measurements used to develop rating (numbers and range of discharge measured), justification for any measurements excluded from rating development, rating equation, applicable dates, and applicable velocity ranges Possible Required
Rationale for selected rating, such as multi-cell analysis and rating type (simple linear, compound, multi-linear), and any applied shifts Required Required
Plots of validation measurements overlain on current line fit (rating) and residuals plots Required
Discussion of validation measurements Possible Required

The term "Possible" indicates that it is possible for the specified information to be documented in that location, however it also must be documented in the location listed as "Required".