ISO 9123:2017 PDF

Scope: This document specifies methods for determining stage-fall-discharge relationships for a stream reach where variable backwater occurs either intermittently or continuously. Two gauging stations, a base reference gauge and an auxiliary gauge are required for gauge height measurements. A number of discharge measurements are required in order to calibrate the rating to the accuracy required by this document. The preparation of rating curves is not described in detail in this document. NOTE For a more detailed description of preparing rating curves, see the methods described in ISO 1100-2.

ISO 9123:2017 Referenced Document

ISO 1088:2007 Hydrometry - Velocity-area methods using current-meters - Collection and processing of data for determination of uncertainties in flow measurement
ISO 1100-2:2010 Hydrometry - Measurement of liquid flow in open channels - Part 2: Determination of the stage-discharge relationship
ISO 18320 Hydrometry — Measurement of liquid flow in open channels — Determination of the stage–discharge relationship*， 2020-08-03 Update
ISO 5168:2005 Measurement of fluid flow - Procedures for the evaluation of uncertainties
ISO 772:2011 Hydrometry - Vocabulary and symbols
ISO/IEC GUIDE 98-3:2008 Uncertainty of measurement — Part 3: Guide to the expression of uncertainty in measurement (GUM:1995)
ISO/TS 25377:2007 Hydrometric uncertainty guidance (HUG)

2017 ISO 9123:2017 Hydrometry - Stage-fall-discharge relationships
2001 ISO 9123:2001 Measurement of liquid flow in open channels - Stage-fall-discharge relationships
1986 ISO 9123:1986 Liquid flow measurements in open channels; Stage-fall-discharge relations