Building Near the Colorado River Means a Floodplain Permit

The Colorado River bends through the middle of Bastrop County, and the low ground along it falls inside a FEMA flood zone called a Special Flood Hazard Area. Build anything in the unincorporated stretches near that water and you'll need a development permit first.

The permit comes in three flavors, and which one you get depends entirely on where your dirt sits relative to the flood line. Class A covers land safely outside the floodplain. Conditional Class A is for land just past the mapped edge but still close enough to worry about. Class B is the strict one, for land partly or fully inside the 100-year flood zone, where the building rules tighten up.

There's a federal wrinkle to keep in mind before you renovate. If you improve a flood-zone structure by more than half its value, the whole building has to meet current flood-proofing standards. That's the 'substantial improvement' rule in CFR 44. In practice it can mean jacking the house up on piers or doing real structural work, so a kitchen remodel on an old riverbank cabin can balloon fast.

Pull the property up at msc.fema.gov to see how it's mapped, then get the county's Floodplain Manager on the phone at (512) 581-7159. Development Services sits at 211 Jackson Street in Bastrop, and they'd rather walk through a pre-application meeting than catch a problem after the slab is poured.