8. Some Traditional Standard Irrigation Weirs

In the past, user organizations selected specific equations from a choice of many, called them "standard," and specified requirements in construction and use to assure full contraction and nearly constant coefficients. Thus, equations and tables for "standard" weirs have strict limits and construction requirements, mainly in terms of the distance of the crest from the approach channel boundaries. In contrast, weir discharge calculated using Kindsvater methods will account for changes in velocity of approach caused by proximity of approach flow boundaries to crests. Thus, a weir designed with the Kindsvater methods can measure and deliver flow with less head loss than a similar "standard" weir mentioned above.