THE bridges of Rome belong to many ancient wonders. Sextus Julius Frontinus (35–c. 103 CE), Roman governor and commissioner in charge of water supplies, * “They were magnificent bridges with more water than the Greeks though they were also famous,” he wrote.
Why Were Bridges Needed?
Many ancient cities were built near abundant water, and so was Rome. Typically, the Tiber River, the valleys near the springs were abundant. From 400 BCE onward, however, Rome grew rapidly and the need for more water increased.
Since few people had access to water in their homes, the Romans built many public and private baths. The first public bath in the city of Rome, the water came from the Aqua Virgo bridge, built in 19 BCE The bridge’s builder Marcus Agrippa, a close friend of Caesar Augustus, donated much of his wealth to improve and expand Rome’s water supply system.
Baths also became public places, the largest of which had gardens and libraries. When water from a bridge passes through the bathrooms, which cannot be replaced, it always flows into the sewerage system to clean up sewage, including bathroom waste.
Construction and Maintenance
When you hear the words, “Roman bridge,” do you think of a structure built like a bow, built to be large? Such buildings make up 20 percent of those bridges, and many of them were started by them. These expensive buildings are not protective not only do they protect the bridges from flooding, but they also protect the fields as well as the properties of their neighbors. The Aqua Marcia bridge, completed in 140 BCE, for example, was 92 miles long but had arched structures 7 miles or more in length.
Before building a bridge, engineers check the water’s purity, depth, flow, and taste. They also consider the health of the people who drink the water. When determining whether construction is appropriate, local surveyors measure the bridge’s flow, depth, and width and length. Slaves were used to build those bridges. Bridges can take years to complete, and they are expensive—especially if architectural structures are needed.
In addition, bridges need to be maintained and protected. To care for them, the city of Rome employed some 700 men. For example, the underside of bridges was designed with an access point. When major repairs were needed, engineers diverted water away from the damaged area.
Bridges in the City of Rome
By the early 200s CE, 11 major bridges supplied water to the city of Rome. The first was the Aqua Appia, built in 312 BCE it was over 10 miles long and its waters flowed underground. The remaining is the Aqua Claudia, some 40 miles [69 km] long with arched structures some 6 miles [10 km] long, many of which are 80 feet [27 m] high.
How much water do city bridges have? They are so many. The Aqua Marcia Bridge, mentioned earlier, carries some 500,000 cubic feet [190,000 cu m] of water a day to Rome. When water reaches urban areas, it is piped to tanks and from there to where it is needed for use. Some estimate that Rome’s water supply was so vast that each citizen received more than 3,000 gallons [1,000 L] of water a day.
As the Roman Empire grew, “so did the water supply of the aqueducts,” says the book Roman Aqueducts & Water Supply. Visitors from Asia Minor, France, Spain, and North Africa still marvel at these ancient engineering buildings.
