Boaters may encounter large commercial vessels anywhere on the Columbia-Snake river system. These vessels have the right of way, since they can navigate safely only within the confines of the navigation channel. It is unsafe and illegal to impede or obstruct these vessels. Upriver from the Bonneville Dam, most of the large commercial traffic consists of barge and tug traffic. These vessels have a significant blind spot that can extend hundreds of yards in front of the vessel, so smaller vessels should stay well clear of this dangerous area. Operators of recreational watercraft should also watch for wakes created by commercial vessels. These wakes can be quite large and dangerous, and they can unexpectedly break as they enter shallow water or meet oncoming currents. Pay close attention to these larger vessels, keep a safe distance, and avoid crossing in front of them.