Short answers, pulled from the story.
Marcus Agrippa became the first Curator Aquarum when Emperor Augustus created the office in 33 BC. He arrived with a workforce of 240 imperial slaves and 40 freedmen to repair crumbling water channels.
Marcus Agrippa served as Curator Aquarum from 33 BC until 12 BC when he passed away from illness. Messala Corvinus took over the role immediately after Agrippa died to continue work on the city's infrastructure.
Emperor Claudius expanded the workforce significantly during his reign, raising the number of men under his command to 460. This growth continued until the total staff reached 700 men who maintained daily operations of the water system.
Lucius Junius Moderatus Frontinus served as Curator Aquarum appointed by emperor Nerva in 97 CE. His tenure marked one of the few times an engineer held the position rather than a ceremonial senator.
Lucius Novius Rufius held the dual title Curator Aquarum et Minuciae while serving as Governor of Hispania Citerior during the joint reigns of Septimius Severus and Caracalla. He was also a supporter of Clodius Albinus who competed against Septimius Severus for imperial power.