AS 3778.3.3:2022 PDF
AS 3778.3.3:2022 identically adopts ISO 1070:2018, which specifies a method of determining discharge in open channels from observations of the surface slope and cross-sectional area of the channel.
This Standard was prepared by the Standards Australia Committee CE-024, Measurement of water flow in open channels and closed conduits, to supersede AS 3778.3.3:2001.
The objective of this document is to specify a method of determining discharge in open channels from observations of the surface slope and cross-sectional area of the channel.
It is applicable to use under special conditions when direct measurement of discharge by typically more accurate methods, such as the velocity-area method, is not possible. Generally, the method can be used to determine discharge —
(a) for a peak flow that left high-water marks along the stream banks;
(b) for a peak flow that left marks on a series of water-level gauges or where peak stages were recorded by that series of gauges; and
(c) for flow observed at the time of determining gauge heights from a series of gauges.
The method is commonly used to undertake the extension of stage discharge relationships above the highest gauged flows.
It does not apply to determining discharges in tidal reaches. This document is identical with, and has been reproduced from, ISO 1070:2018, Hydrometry — Slope-area method.
As this document has been reproduced from an International document, a full point substitutes for a comma when referring to a decimal marker.
