Samples of the Story
Preface
Author’s Note
1. The Elixir of Life
2. Farmers and Furrows
3. “Whoever has a channel has a wife”
4. Hohokam: “Something that is all gone”
5. The Power of the Waters
6. Landscapes of Enlil
7. The Lands of Enki
8. “I caused a canal to be cut”
9. The Waters of Zeus
10. Aquae Romae
11. Waters that Purify
12. China’s Sorrow
13. The Water Lily Lords
14. The Triumph of Gravity
15. The Waters if Islam
16. “Lifting Power more than that of a Hundred Men”
17. Epilogue
Notes
Acknowledgements
Index
| Book Extracts and Table of Contents
Chapter 9: The Waters of Zeus
During the first century B.C.E., a Roman engineer, Marcus Vitruvius Pollio (c.80-15 B.C.E.), wrote a ten-volume treatise on architecture in which he summarized the now-lost works of Greek engineers of the sixth to fourth centuries. He devoted his eighth volume to water and wrote of how rain and snow accumulated on Greek mountainsides: “Afterwards in melting, it filters through fissures in the ground and thus reaches the very foot of the mountains from which gushing springs comes belching out.” He put his finger on the basis of much Greek water management—the unique qualities of karst formations. (Karst is terrain of porous limestone containing deep fissures and sinkholes marked by underground caves and streams.) Vitruvius had ample grounds for respecting Greek water engineers. Between the eighth and fifth centuries, the Greeks were building cities that were increasingly complex and that required careful management of water sources, distribution, usage, and discard. That they were able to do so for centuries is a testament to the remarkable skill of their water experts and especially to their geological expertise.
Carbonate rocks define much of the Mediterranean landscape, laid down and uplifted over millions of years when the sea alternated with dry land. These strata consist of limestone layers, dolomite, or marble. Karst forms where limestone interacts with water to create sinks, ravines, and other surface features, also underground water tunnels. It most commonly occurs where soluble rock lies under a permeable but insoluble formation like sandstone. Water flows underground in aquifers through karst, some of it accumulating in conduits such as cave systems, others more diffuse, and often seeping through joins in the rock. An irregular and usually discontinuous water table can form multiple layers, while springs are common on the surface. Much of the water used by ancient Greek villages and cities had a high calcium carbonate load in the form of sinter, fine dust resulting from the corrosion of limestone. Sinter accumulation was a constant problem in their pipelines and posed a serious maintenance challenge.
The shafts and channels in karst formations act as natural pipelines; dolines (closed depressions) and sinkholes form places where surface water drains into the rock through fissures. Caves, many of them deep underground, often contain springs and sometimes serve as natural pipelines. All this makes a superb reservoir for drinking water. Such formations abound in springs, which usually appear at the base of a mountain, where a layer of soluble limestone abuts an impermeable stratum of stone or clay. Dora Crouch and others have referred to Greek mountains as giant water towers, which provided high infiltration and low runoff, with the karst even forming water tables at high altitudes—the equivalent of humanly constructed Maya “water mountains” in Central America.
Karst yields perennial rivers and springs, both of which can be tapped to supply water over considerable distances. Such springs are not uncommon. In the southwestern Peloponnese alone, there are 2 major and 118 minor springs, also 26 rivers that lend themselves to simple irrigation schemes. The settlement pattern of ancient Greece reflects the widespread distribution of karst water supplies of all kinds, exploited with simple technologies that enabled people to live in all manner of local environments and helped turn Athens from a village into a city.
Attica, with its capital Athens, was home to between 200,000 and 300,000 people during the fifth century B.C.E. (Estimates vary widely.) The limestone Acropolis with its shrines and temples was the focus of the city itself, a place where Mycenaeans used a spring as early as the thirteenth century B.C.E. The Acropolis might have had defensive appeal, but its real attraction was its springs and water seeps. As early as the sixth century B.C.E., large roofed cisterns fed by rainfall formed a square inside the Acropolis wall. These complexes with their supply and drainage channels were apparently dug for defensive reasons. A series of springs and some water-bearing caves girdle the Acropolis, formed by percolating water reaching a layer of relatively impermeable schist and marl, then appearing on the surface in the form of small springs. The Acropolis is, in effect, a huge reservoir. Five additional cisterns dug just north of the Parthenon may have served the needs of visitors during major festivals.
The natural springs of the Acropolis were insufficient to supply the water needs of the rapidly growing city. From the earliest times, the Athenians clustered at its foot dug shallow wells or pits to tap the groundwater. They used fired clay pipes to draw water from the springs and seeps on the north side. A network of wells developed through the city, reaching outward to the outskirts of Athens.
These supplies proved too inadequate for the growing city. In about 510 B.C.E., the tyrant Peisistratos and his descendants built an aqueduct that carried water from the Kephissos spring at the foot of Mt. Pentilicus. A second line from Mt. Ymettus joined the first in a large reservoir. The aqueduct spanned a distance of over 4.5 miles (7.5 kilometers) to the center of the city near the Acropolis, much of it a tunnel, reaching a depth of 46 feet (14 meters) in places, the remainder a rock-cut or masonry block channel. A ceramic pipe carried water through the aqueduct, each section having elliptical covers for maintenance. The ends interlocked tightly with lead-sealed seams. Much later, the 2nd-century Roman occupiers of the emperor Hadrian’s day commissioned another aqueduct, which ran from nearby mountain to a reservoir on Lycabettus Hill. This was effectively a qanat, with air shafts at 98 to 131-foot (30-40-meter) intervals. Some of the tunnels were large enough to stand in, but in most of them the workers crawled on their hands and knees. Both aqueducts were enormous construction projects by the standards of the day, and must have involved slave labor. Underground pipes carried the water through the city. There were also sewer lines and large storm drains, some of them still in use today.
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