To find out FEMA flood plains you would contact Mohave County Flood Control, ask for Deleta @ 928-757-0925. The parcel number for this property is 306-50-001B. She will able to tell you.
Also, please know there is a difference between a property being in a flood zone and having a wash that runs through it. Looking on the Mohave County maps it appears there is a small wash that runs in the back of the property. Here in Golden Valley, that's very common.
I'd be more than happy to help if you require more assistance. Please don't hesitate to contact me, I'm always available:
Silver Sage Properties
Golden Valley, AZ