Abstarct: When the stracture placed in the river bed, makes changes the river flow. This changes increase the capacity of sediment transport by water and Will eventually lead to scour. Bridges are the most important river stractures and the important problem of Vulnerability the abutments in flood plain in local scour cape of them. Maximum depth scour is one of the important parameters in the design and It is important to determine the depth of scour that indicate the potential for water damage around structures. Also, because of the process of scoring, to maintain the stability of bridges during floods need to put the big foundations are deep, Leading to imposed great costs on the construction of bridges. In this study, in order to reduce the amount of scour at bridge abutments in flood plain suggest a protective spur dike structures used to determine the distance and the length of the wing. The main purpose of this research is the study of the maximum depth of scour bridge abutments And the effect of distance and wing length of protective Spur Dike in flood plain of compound channel . First experiments on discharges, 18, 20, 22, 24 and 26 liters per second without spur dike (control) was performed, then with placing the spur dike of impermeable, rigid, non-submerged, vertical and T-shaped symmetries of 0/2, 0/5, 2 and 5 for wing of spur dike and at 9, 18, 27, 36 and 45 cm from the abutment, the experiments was repeated in the discharges. With reviews of the Hydraulic parameters Affecting the scouring like discharge, flow depth, mean velocity and Parameters related to the geometry of the spur dike like wing length of the spur dike, the distance from the abutment and Dimensional analysis of the factors, Dimensionless Equation is obtained With taking some of the parameters have been constant. Also, the equation for the maximum scour depth around abutments in different conditions is presented.