In Fallout 3, they appear frequently in the Tidal Basin and the Potomac River, as well as in small lakes. They never directly contain loot, but sometimes hold lootable containers, and come in a variety of colors.
In Fallout: New Vegas, they appear mostly in Lake Mead, though some do appear in the add-onHonest Hearts. They never directly contain loot, but sometimes hold lootable containers, and come in a variety of colors. They can be seen towed behind trucks, such as at the boat launch at Callville Bay.
In Fallout 4 and Fallout 76, rowboats take on a more traditional wooden look and are found mostly on beaches and in boathouses.
Locations
Several row boats can be found sunk under Lake Mead, along with other, larger fishing boats.
Towed by a truck at Callville Bay.
A row boat is also located inside the entrance to the flooded metro station.