Like many extinct civilizations, the ancient Mayans may have eventually just grown too big for their own brilliance. Tikal, for instance, once supported 60,000 to 80,000 inhabitants—part of an estimated population of five million in the overall Maya lowlands by AD 700. And like us, they also relied on dams to manipulate environments to help foster lots and lots... and lots of people. Archeologists recently unearthed one of the biggest dams of the times in Tikal—believed to be the beginning of the end for the elusive Guatemalan steelhead.
Via the Summit County Voice: "Archaeologists have long known that the Maya were sophisticated engineers, but new excavations at Tikal, Guatemala, show the amazing extent to which they were able to manipulate the environment to their advantage, including construction of 260-foot dam that stored up to 20 million gallons of water.
"That dam—constructed from cut stone, rubble and earth—stood about 33 feet high and held about 20 million gallons of water in a man-made reservoir."Source Link