“The Bayou City” for nothing!
Updated: Feb 11
We don’t refer to Houston as “The Bayou City” for nothing! Have you ever wondered why? It covers 1,788 square miles with 1,500 channels totaling about 2,500 miles in length within twenty-two watersheds. Each bayou and creek include areas known as "floodplains," where water collects, pools, and flows during the course of a natural storm event.
A floodplain is defined as any land area susceptible to being inundated by water from any source. These areas are classified as Special Flood Hazard Areas (SFHA) and are located in a 100-year flood zone. The term "100-year flood" can be misleading. It does not mean that the flood will occur every 100 years; rather it is the flood elevation that has a 1- percent chance of being equaled or exceeded each year. Harris County has Flood Insurance Rate Maps (FIRM) that identify all floodplain areas within the county limits.
Before you acquire a property or pay for blueprints (especially foundation plans), you need to know the flood plain designation of the lot. You can easily do so by going to https://www.harriscountyfemt.org/. If the property is located in the 500-year / 100-year / or Conveyance floodway, then you will require additional documentation prior to designing your foundation plans.
In addition to a standard boundary survey, you will also need an Elevation Certificate, which determines the property’s Base Flood Elevation (BFE). If the property is located in the 500-year or 100-year flood plain, the top of your foundation must be designed at least 24” above the BFE. Other documentation which may be required for a property in the flood plain includes but is not limited to a Topographical Survey, and a Drainage Plan.