Design of Stable Alluvial Canals in a System

Abstract

A graphical method for the design of stable alluvial canals connected in a distributary system is presented. Under a given plan for water distribution, this method may be used to determine the stable width, depth and slope of each canal in the system. It has the advantages of relative simplicity and handiness as a design tool. Because of the sediment problems in systems design, the geometries and slopes of all canals in the same system must be interrelated in order to maintain sediment equilibrium. Without the use of structural sediment controls, sediment equilibrium is maintained by designing canals with an equal sediment concentration. Under such a system design, the power expenditure per unit weight of water stays approximately the same throughout the system; and the channel slope is inversely proportional to the one‐sixth power of the discharge. Canals with greater discharges have higher velocities but flatter slopes.