I got an email in my inbox yesterday from Dr. Bill Hunt, an agricultural engineering professor and Extension specialist at NC State University. He is offering a study tour and a series of webinars on Roman engineering. It is mind-blowing that, thousands of years later, the innovations and expertise of an ancient civilization are relevant enough to offer continuing education for professional engineers in 2024.
Roman engineering is truly a marvel. Between the roads, aqueducts, buildings, temples, and entertainment complexes, even the modern eye is impressed with the scale and mastery of their design and construction. They were even centuries ahead of their time when dealing with stormwater drainage.
During our recent trip through the Tuscan countryside, my family visited the medieval city of Siena. Originally an Etruscan settlement between 900-400 BC, it became part of the Roman Empire in the 1st century AD. One of the famed “hill towns” of this region, the city is constructed on terraces and steep slopes with narrow, winding streets. At the city center is the Piazza del Campo, which is the hub of numerous streets that open into this gathering area and the stunning University of Siena, one of the oldest continually operating universities (1240) in the world. The plaza was constructed around the same time as the university, and by this time Siena was a self-governing province, in competition with Florence.
I noted that the brick plaza was not flat, but a bowl/fan shape that funneled towards a central collection point. At the lowest elevation was a giant decorative metal grate, shaped like a scallop—quite similar to the shape of the huge plaza, itself. It was clear to me that I was likely looking at one of the world’s oldest stormwater drains. The way this drain was situated, any water from the entire hilly city could easily collect in the plaza and drain into this large opening. It even has a name, the Gavinone.
This drain leads to an elaborate underground aqueduct system, the Bottini (a reference to a term for rounded vaults). Due to Siena’s high elevation and lack of a nearby water source, the storm drains, underground vaults, and associated fountains formed a complex cistern and water distribution system. In a method remarkably similar to Florida’s surface water quality classification system, the Sienese divided the water into three basins. According to Visit Siena, “in the first there was ‘new water’, so drinking water; the second (fed by the overflow of the first) is where the animals would drink; while the water of the third was used for washing clothes. The water coming out of the last basin was then used by tanners, in dying workshops and by millers to power the mills along its course.”
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