What Zone AE means, and the Nashville lesson behind it

Flood zone is the field most often skipped and most expensive to get wrong, so here is the plain version.

FEMA maps parcels into zones. Zone X is outside the mapped special flood hazard area. Zone AE is inside it, with a base flood elevation established. Some Zone X areas carry a shaded designation for the 0.2 percent annual chance flood, which is the one people call the 500 year floodplain, and that is a different thing from Zone AE.

If your parcel is in Zone AE and you have a federally backed mortgage, flood insurance is required, not optional. That is a real monthly number and it belongs in your budget from the beginning rather than showing up two weeks before closing.

Here is what the maps actually look like on the ground in Davidson County. In Antioch Park and Crittenden Estates, mapped Zone AE runs through the body of the subdivision. In Hermitage Hills and Merry Oaks, the mapped floodplain sits at the margins and the interior is clear. Traceside in Bellevue is not a riverfront neighborhood and still has mapped Zone AE inside it. Kingsway Green in Madison, Summerfield Village in Antioch and Evergreen Hills return no mapped floodplain at all. Neighborhood reputation is a poor guide to any of this.

The 2010 flood is the reason I push on it. The Harpeth at Bellevue crested at 33.32 feet, nearly nine feet above the 1948 record, and the gauge itself washed away. The Harpeth Conservancy records more than 146 Bellevue homes destroyed. And a fact most people find surprising: Metro Water Services never ran a buyout project in Bellevue. Its six buyout areas were Delray Drive and West Hamilton, Hite Street, Benzing Road, Miami Avenue, Pennington Bend and Yale Avenue. Bellevue was hit hard and was not bought out.

So what do you do. Pull the FEMA map on the specific parcel, not the subdivision. If it is in or near Zone AE, get an elevation certificate before your contingencies come off, because the elevation certificate is what determines your actual premium and it can differ enormously from the zone alone. And ask the seller directly whether the property has ever flooded.

None of this means do not buy near water. It means know exactly what you are buying, and price the insurance in from day one.