Angrivarii
The wars began in the last years of the reign of Augustus, first emperor of Rome. Augustus died an old but respected man in the year 14 and was celebrated with much pomp and splendor. He left a document to be read to the senate posthumously, expressly forbidding extension of the empire beyond the Rhine. News of the will was welcomed by the Germans, thinking it gave them a free hand in the region. Germanicus found it necessary to pacify the border, which he did by a combination of scorched earth raids and offers of alliance with Rome - in short, stick and carrot. These raids also kept the army of the lower Rhine distracted from the possibility of mutiny, which had broken out on Augustus's death and only been quelled by concessions and executions.
Augustus
He also built the Temple of Caesar, the Baths of Agrippa, and the Forum of Augustus with its Temple of Mars Ultor. Other projects were either encouraged by him, such as the Theatre of Balbus, and Agrippa's construction of the Pantheon, or funded by him in the name of others, often relations (e.g. Portico of Octavia, Theatre of Marcellus). Even his Mausoleum of Augustus was built before his death to house members of his family. To celebrate his victory at the Battle of Actium, the Arch of Augustus was built in 29 BC near the entrance of the Temple of Castor and Pollux, and widened in 19 BC to include a triple-arch design.
After the death of Agrippa in 12 BC, a solution had to be found in maintaining Rome's water supply system. This came about because it was overseen by Agrippa when he served as aedile, and was even funded by him afterwards when he was a private citizen paying at his own expense. In that year, Augustus arranged a system where the Senate designated three of its members as prime commissioners in charge of the water supply and to ensure that Rome's aqueducts did not fall into disrepair.