Whether or not a street floods depends on it's location. Some streets have not been raised and above-normal tides can cause water to come out of the storm drains into the street. Many houses in flood areas do not have basements but those that do are not usually affected by this small amount of water at the curb.
About once every 20 years or so, there is a hurricane or a nor'easter. Then flooding can be more severe. If you are considering buying a house south of Atlantic Avenue, your lender will most likely require flood insurance. If the house has a below ground basement, a good home inspector will be able to tell you if there is evidence of flooding. That doesn't mean you shouldn't buy the house. It just means you should be aware of the possibility it may happen again and you shouldn't keep anything valuable on the basement floor.
If you are still looking for a house, I would be happy to help you with your search. As a buyers' agent, I work on your behalf to help you find the right house at the right price. Call me at 516-410-3000. I will answer any questions you have about buyer representation.... more