From Iranmania:

An Iranian archeologist has claimed that he found evidence supporting claims that the Greek conqueror Alexander of Macedonia had flooded the ancient city of Hegmataneh, or modern day Hamedan, as a means of breaking the city’s defenses.

Mehdi Aqakhani wrote in an article that the contention cannot be denied since it is also backed up by accounts attributed to an Assyrian king, reported ISNA.

According to the legend, after Alexander of Macedonia failed to capture of the city of Hegmataneh, he sent a map of the city to the famous Greek philosopher Aristotle seeking his advice on how to overrun the city. Aristotle advised Alexander to build a dam six kilometers from Hamedan city and then, after a year, break the dam and channel the water toward the city. In this way the city can be captured.

Aqakhani pointed out that the claim is supported by the presence of layers of sand in the northern section of Hegmataneh hills. A thick sedimentary layer was discovered during the 15th round of excavations in Hegmataneh hills which serves as evidence that the city was indeed flooded before being captured.

Hegmataneh will be more familiar to Classics types as Ecbatana ... I've never heard of this story before.