Check the sellers disclosure to see if the owner marked that they had knowledge of the flood plain or if they pay flood insurance. (pg 2, right column if using IAR forms)
In Indiana, flood insurance maps are changing. If you , your agent, nor the seller believes that the property is in a flood plain, have a elevation survey completed. Once the flood plain has been established, you can complete a letter of map amendment (LOMA) with FEMA to remove the property from the flood plain map if you are above the 100 year flood plain. This is quite common in Kosciusko, Marshall & Fulton counties. (noted that you are in Rochester, IN ) It is always best to disclose flood plain issues up front as there may be ways to work around the issue with different lenders requirements. Some lenders require if any portion of the lot to be in a flood plain to require flood insurance. on a lake house, this is nearly impossible as the water touches to the lot somewhere in the flood plain. Other lenders measure from the elevation of the first livable floor or a structure.