Houston may force hundreds of residents to raise their homes

The Houston Chronicle ran another front page article today regarding flooding issues in Houston.  The title is "Harvey damage could force hundreds in Houston to raise their homes" by Nancy Sarnoff.

To summarize some property owners that flooded during Harvey will need to elevate their homes if they want to continue living there.  If the affected properties are substantially damaged and not currently compliant with the city's current elevation standard they will be required to bring the property into compliance.  The standard is that the lowest floor must be 12 inches above the base flood elevation (BFE), or 18 inches in a floodway.

The initial group of properties to be notified of this new requirement does not include any in the Clear Lake City area, although the article implies that there are more properties yet to be notified.  According to the map included in the article, the zip code 77089 is the closest area to Clear Lake with a significant number of properties (90) affected by this.  That is the Southbelt/Ellington/Scarsdale area near the intersection of I-45 and Beltway 8.

In Clear Lake City there are approximately 100 homes that are currently within the 100-year flood plains (see map).  Many others are partially within the flood plain.  The largest clusters of these homes are in Bay Glen and Bay Oaks.
These neighborhoods were built after the implementation of the standards for construction within flood plains, which for most of Clear Lake City were put in effect in the early 1970s.  However whether or not a home will actually flood is dependent on many factors beyond the elevation of the lowest floor above the BFE.  One notable mitigating factor is the elevation of the home slab above street level.  This can range from 5-6 above the street in Bay Oaks to 2-3 feet below the street in Brookforest.

From what I have observed many of these homes and others nearby were damaged by Harvey flooding however there are many exceptions.  Please comment if you have knowledge of significant damage to homes located outside of the mapped flood plains. Alternatively it would be of interest to explore factors that prevented flooding damage in the high-risk areas associated with the SFHAs.

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