Locally correct pronunciation of Au Sable

For an upcoming project I will need to read the name of the Au Sable river aloud, and I am wondering how the first part is pronounced in the area. My very limited knowledge of French would incline me to say it Oh, but it also seems possible that it might be Ow or Aw, or even possibly Oo. I live near Pulaski and not too far from Vienna, so the way foreign vowels can get altered in New York is not unfamiliar to me. I am assuming that the Sable part is said like table, but if it's not I'd like to know that too. I'll be very grateful for any advice.