Purchasing a house in a 100y flood zone

[Terence Mcneil]

Hey BP, I recently had a offer accepted on a house in Austin TX, the backyard backs up to a creek that is in a 100y flood zone. The house however sits on the 500y flood zone. I'm familiar with what the zones are, however how much of a concern for reseal down the line should I have? I understand flood insurance will need to be purchased.