It's orange county utilities

It was AT&T.

Orange County utilities water bill

When I called back to this number, a recording said this number do not accept incoming calls.

I got a call from this number saying it is Orange County Utilities and asked me to pay a balance $33.35 (while my account has been set up for auto pay for years).  It sounds totally professional without a doubt.  However, I still called the "real" Orange County Utitlites later on and confirmed that my account has no outstanding balance.