A method of assembling a lock and dam system is disclosed to minimize the rate of structural fatigue associated with closing of the lock and dam system. The lock and dam system includes one or more gates that may include a plurality of girders, plates and associated support or reinforcing members. The gate has a miter end and a quoin end. On the miter end a miter block, and thrust plate transfer impact forces associated with closing of the gate from the point of impact to the remainder of the gate. The thrust plate is preferably a substantially uniformly thick member that is secured vertically to the gate through a slot cut or formed in the end of the horizontal plate on the miter and quoin end. Preferably, the thrust plate is secured using a fillet weld.