A watertender is a crewman aboard a steam-powered ship

Steamboat

A steamboat or steamship, sometimes called a steamer, is a ship in which the primary method of propulsion is steam power, typically driving propellers or paddlewheels...

 who is responsible for tending to the fires and boiler

Boiler

A boiler is a closed vessel in which water or other fluid is heated. The heated or vaporized fluid exits the boiler for use in various processes or heating applications.-Materials:...

s in the ship's engine room

Engine room

On a ship, the engine room, or ER, commonly refers to the machinery spaces of a vessel. To increase the safety and damage survivability of a vessel, the machinery necessary for operations may be segregated into various spaces, the engine room is one of these spaces, and is generally the largest...

.

In the United States Navy

United States Navy

The United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined. The U.S...

, "watertender" (abbreviated WT) was a petty officer

Petty Officer

A petty officer is a non-commissioned officer in many navies and is given the NATO rank denotion OR-6. They are equal in rank to sergeant, British Army and Royal Air Force. A Petty Officer is superior in rank to Leading Rate and subordinate to Chief Petty Officer, in the case of the British Armed...

 rating which existed from 1884 to 1948. Watertenders held a paygrade equivalent to today's petty officer first class

Petty Officer First Class

Good conductvariation,12 years or moreof good conductPetty officerfirst classinsigniaU.S. Navy &U.S. Coast GuardPetty officer, first class is the sixth enlisted rank in the U.S. Navy and U.S...

. A chief

Chief Petty Officer

A chief petty officer is a senior non-commissioned officer in many navies and coast guards.-Canada:"Chief Petty Officer" refers to two ranks in the Canadian Navy...

 watertender (CWT) paygrade was established in 1903. In 1921, the lower paygrade was split into watertender first class (WT1 or WT1c) and watertender second class

Petty Officer Second Class

Good conductvariation,Petty OfficerSecond Classinsignia&U.S. Coast GuardPetty officer second class is the fifth enlisted rank in the U.S. Navy and U.S...

 (WT2 or WT2c). Another lower paygrade, watertender third class

Petty Officer Third Class

U.S. NavyGood conductvariationU.S. NavyPetty officerthird classinsigniaPetty officer third class is the fourth enlisted rank in the U.S. Navy and U.S. Coast Guard, just above seaman and below petty officer second class, and is the lowest rank of non-commissioned officer, equivalent to a corporal in...

 (WT3 or WT3c), was established in 1943. The watertender and boilermaker

Boilermaker

A boilermaker is a trained craftsman who produces steel fabrications from plates and sections. The name originated from craftsmen who would fabricate boilers, but they may work on projects as diverse as bridges to blast furnaces to the construction of mining equipment.-Boilermaking:Many...

 ratings were merged into a new "boilerman" rating in 1948.