Iranian engineers began filling a new dam as archaeologists warned that its reservoir will flood newly discovered antiquities and could damage Iran's grandest site, the ancient Persian capital of Persepolis. At the inauguration ceremony Thursday, attended by Energy Ministry officials, pipes were opened for water to start flowing into an artificial lake created by the dam spanning the Sivand River, 840 kilometers (520 miles) south of the capital, Teheran. The lake's waters will be used to irrigate the area's farms. Iranian state-run television said the dam was opened "on the order of the President" Mahmoud Ahmadinejad, but the hard-line Iranian leader did not attend the inauguration. Archaeologist Parviz Varjavand said "irreplaceable human heritage" will be lost. "This ruling establishment gives no value to Iran's cultural heritage. It is an act of stupidity and obstinacy," he said.