New flood plain rules for Harris County


The title of a front page article in today's Houston Chronicle is "County tightens flood plain rules - more rigorous standards for new development could impact growth".


The result is that there will now be new, tougher regulations for flood plain development in Harris County.  New construction will be required to be built to the 500-yr storm standard rather than the current 100-yr standard.

For Clear Lake City the 500-yr floodplain (yellow on the display below) covers much more area than does the 100-yr (green and blue on the display).  The change to the new regulations would effectively
be a large expansion of the current SFHAs.  For example the Reserve at Clear Lake City currently under development would have to consider the 500-yr flood plain over the southern third of the area.  At present the entire area is mapped as minimal flood risk.  

These changes could call attention to the greater flooding risk that is now a reality. Since 2015 three 500-yr (or larger) storms have caused significant flooding in the area.  Based on this recent history residents and or prospective homebuyers may want to place more emphasis on the 500-yr floodplain when evaluating potential flooding risk.

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