Short answers, pulled from the story.
The Aqua Marcia was built between 144 and 140 BC. Construction was overseen by the praetor Quintus Marcius Rex, for whom the aqueduct is named, and was funded largely by spoils from Rome's conquests of Corinth and Carthage in 146 BC.
The Aqua Marcia is 91 kilometers long, making it the longest of the eleven aqueducts that supplied ancient Rome. The first 80 kilometers ran underground, with the final stretch carried on monumental arches into the city.
The Roman Senate commissioned the Aqua Marcia after the city's two existing aqueducts, the Aqua Appia and Aqua Anio Vetus, had become dilapidated and illegal diversions had reduced their flow. The praetor Quintus Marcius Rex was entrusted with supervising the work.
Around AD 97, the administrator Frontinus measured the Aqua Marcia's flow at its source as 4,690 quinariae, making it the second-greatest water source in Rome. Modern estimates translate this to between 46,900,000 and 360,192,000 liters of water per day, depending on the size assigned to one quinaria.
The same springs that fed the Aqua Marcia supply the modern Acqua Felice aqueduct, which has been running since 1586 and follows long stretches of the ancient route. The water source chosen in 144 BC remains in daily use.
Ponte Lupo is a surviving bridge of the Aqua Marcia built in 144 BC to carry the aqueduct across the deep Aniene Valley. It stands more than 30 meters high and over 80 meters long, and once carried a road along its top connecting the two sides of the valley.