Ezra 8:15: Verse 15
The river that runneth to Ahava - Ahava was a river itself, which is supposed to be the same that is called Diava or Adiava, in the province of Adiabene; and perhaps the place whence the people of Ava came who were brought by the king of Assyria to Palestine, 2Kgs 17:24.
None of the sons of Levi - None that were simply Levites. He found priests, and they were sons of Levi; but no Levites that were not priests.