InfoDrainage 2021.1 Help Documentation infodrainage2021v1

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The method was originally published in 1941 and its use by practitioners was recommended from 1949, then the method was revised in 1977 [1]. The implementation in InfoDrainage is based on the description in the reference guide ‘La Ville et son assainissement’ [2].

title Sizing

The Pipe sizing method used in InfoDrainage is the same whichever flow calculation method is selected.

This option may not be available for your region. For more information, refer to the Regionalisation topic.

The equations

The main formula used by the ‘Méthode de Caquot’ is as follow:

where I is the average slope of the catchment (m/m), C is the runoff coefficient of the catchment (generally assumed equal to the coefficient of impermeabilisation), and A is the catchment area (ha).

The coefficients  are calculated using the advanced parameters according to the following equations: