A hydraulic steering system for a watercraft has first and second hydraulic steering actuators for steering first and second outdrives respectively, at least one hydraulic pump selectively supplying hydraulic pressure to at least one of the first and second actuators, a steering controller operatively connected to the at least one pump, a hydraulic helm selectively supplying hydraulic pressure to the first and second actuators, an auxiliary steering input device connected to the controller, and at least one mode selection valve having first and second mode positions for steering the watercraft in first and second steering modes respectively. In the first steering mode, the hydraulic helm is hydraulically connected to the first and second actuators. In the second steering mode, the hydraulic helm is hydraulically disconnected from the first and second actuators. A watercraft having the steering system and a method for steering a watercraft are also disclosed.