Flood plain and flood zone

Flood Plain

Flood plains are typically considered an area of land in the vicinity of a body of water (stream, river, lakes, and coastal or tidal waters) that may be affected in the event of a flooding or rising of the water level of that body of water. Simple example: You’ve got a stream running 50 yards from your back property line. If and when that stream floods, if the flood plain for that stream extends into your yard then your land is in the flood plain and you may have a problem. Flood plains are classified by the risk or calculated regularity of the flood. An annual flood plain can expect a flood once a year, a 100 year flood plain is expected to flood once every 100 years (or it has a 1% chance of flooding per year).

You can usually check with the local building department or FEMA to see what the flood plain elevation is in your area. They have maps that show the water bodies (lakes, streams etc), and the elevations for the 100 year flood plain. If that elevation is (for example) 50, and the property you’re looking to buy is at 45, you’ve got problems. You’ll either have to buy flood insurance (often not cheap), or add fill to the lot to get your home above that elevation – also not cheap!

Flood Zone

The term Flood Zone is a rating system of flooding risk used by insurance companies. The Flood Zone a piece of land is located in will have an effect on your insurance rate and possibly call for additional requirements in the building of a home on that land. For example, in some low lying coastal areas where flooding is likely the first floor of homes are required to be raised up. Depending on the location, homes may be required to be raised a few feet or over 15 feet! Other requirements include flood vents to be built right into the home. In the event of a major flood, these allow water to literally flow right through and under the home. Check with the local town or county offices to determine what flood zones your potential lots may be in. Flood insurance can be expensive depending on the flood zone so do your homework before you buy!