Although I am a REALTOR in the STATE of SC, I have had previous experience many years ago as a Licensed Insurance Agent. We were required by the state to know all Insurance Laws regarding Flood Insurance requirements, flood plains, how to read flood maps, etc.
I would recommend for you to look on the following website: http://www.FLORIDADISASTER.ORG. This is an organization that can answer your question plus offer you a wealth of more information regarding Flood areas, etc.
Also, a reputable Insurance Agency in your town would be able to tell you if this area or street address is or is not in a flood plain and whether or not you must purchase flood insurance if the home has a mortgage.
In SC, if your home is NOT in a flood plain area, you "cannot" purchase flood insurance, and this is really a sad problem. When Hurrican Hugo hit my hometown of Rock Hill, SC (20 miles south of Charlotte, NC), homes were ruined and areas were flooded and homeowners policies did NOT cover the damages because the owners could not purchase the flood insurance and the hurricane damage was considered an "act of God". It was truly a devastating experience to say the least.
I wish you well and hope that this small bit of info will be of help to you.
Rock Hill, SC
They have VERY (last 6-8 months) recently updated the flood maps for the state of Florida. What was not in a flood plain last year, may well be in one this year. Every great REALTOR tries to keep current with this type of information, but your absolute best bet is to consult an insurance professional in the Port Richey area. Any responsible REALTOR would advise you to do the same (we are not insurance experts). Best wishes!