This study focuses on the hydraulic conditions of submerged small overspill dams. Based on a definition scheme, the study proposes a simple relationship, punctuated by a single curve, which predicts the submerged or unsubmerged nature of the spillway dam. The resulting relation is the solution of a second-order equation. From the known values of the upstream depth h of the flow relative to the crest elevation, the unit flow discharge q and the geometric height s of the weir, it is possible to know whether the weir dam is submerged or unsubmerged. The study shows that a second-order equation governs the downstream depth rate w. The solution of this equation is an explicit relation which permits calculating the downstream depth rate for the given values of h, q and s. Finally, the study proposes an explicit relation for the calculation of the submersion rate b when the parameters h, q and s are known.


Overspill dam, submergence rate, downstream depth rate, sill, unit flow discharge.

Full Text:

PDF (Français)


ACHOUR B., BOUZIANE T., NEBBAR K. (2003). Débitmètre triangulaire à paroi épaisse dans un canal rectanguliare (Première partie), Larhyss Journal, n°2, pp.7-43.

BAZIN H. (1894). “Expériences nouvelles sur l’écoulement en déversoir.” Vol. VII, Annales des Points et Chaussées, Mémoires et Documents.

BOS M.G. (1976). Discharge measurement structures, hydraulic laboratory, Wageningen, The Netherlands, Rapport 4, May.

COX G.N. (1928). “The submerged weir as a measuring device.” Bulletin engineering experiment station series no. 67, Univ. of Wisconsin, Madison, Wis.

FALVEY H.T. (2003). Hydraulic design of labyrinth weirs, ASCE, Reston, Va.

FRANCIS J.B. (1884). “Experiments on the flow of water over submerged weirs.” Transactions of the American Society of Civil Engineers, n°13, pp.303–312.

FTELEY A., STEARNS F.P. (1883). “Description of some experiments on flow of water made during the construction of works for conveying water of Sudbury River to Boston.” Transactions of the American Society of Civil Engineers, n°12, pp.101–108.

HOUICHI L., ACHOUR B. (2007). Flow depth computation at the toe of an over-flow dam in steeply-sloping case, dam Engineering, Vol.XVII, Issue 4, pp.245-256.

REHBOCK T. (1929). Wassermessung mit scharfkantigen Ueberfaellen, Zeitschrift VdI, Vol. 73, pp.7-823.

SIA (1926). Contribution à l'étude des méthodes de jaugeages, Bull. 18, Schw. Bureau Wasserfoschung, Bern.

VILLEMONTE J.R. (1947). “Submerged weir discharge studies.” Engineering News-Record, Vol.139, n°26, pp.54–56.


  • There are currently no refbacks.

Creative Commons License
This work is licensed under a Creative Commons Attribution 3.0 License.