Riverman
While there are roads that connect the main cities and towns of the Valley, the river is by far the best method of transporting goods, people, and information. While the riverboats travel downriver, most only need a few people to run them, as the current does most of the work. However, Rivermen are hired by captains looking to travel against the current upriver.
Career
Qualifications
Rivermen are, generally, considered unskilled labor in the valley. They are strong, burly, and capable of working for hours on end without rest.
Career Progression
While many men looking to make some quick money will sign on as a Riverman, there is a class of Rivermen that have been given a certification. Rivermen looking to make good money strive to be hired by Fischer shipping company out of Vedan, as riverboat captains who work for this company are authorized to hand out notes of certification to Rivermen who they see as particularly skilled. These Rivermen receive special benefits not only on these riverboats, but any riverboat they are hired on.
Payment & Reimbursement
Rivermen are paid based on the speed at which the riverboats they are on reach their destination. On top of this, Certified Rivermen are guaranteed a small cut of the sales of the goods the riverboat is carrying. There are also bonuses available if the ship is carrying fragile wares and none are broken in the journey.
Certified Rivermen also receive free travel downriver on most non-passenger riverboats. Uncertified Rivermen receive a discount or are given free travel if they assist in the riverboat's journey.
Operations
Tools
There are two types of ways that riverboats travel upriver in The Valley. The first is by poles, and the second is by oars. Which one it is depends on the type of ship that is hiring. Some Rivermen specialize in one method or the other.
They are not expected to provide their own equipment, as each ship is custom-built and may require unique tools.

Great article, nicely detailed :)