Does flooding occur outside of a FEMA-mapped floodplain?
Yes. Some flood hazards simply arent mapped on FEMA Flood Insurance Rate Maps (see questions on ponding and overland sheetwater flow), nor is every small tributary in the county included. The mapped floodplain is only an estimate of where flooding is predicted to occur given a set of parameters which include a hypothetical rainfall that occurs over a watershed for an assumed amount of time. During an actual rainstorm, natural conditions can result in greater amounts of rainfall or runoff, resulting in flood levels deeper and wider than shown on the FEMA Flood Insurance Rate Maps. On June 19, 2006, sheet flooding occurred outside the mapped floodplains in Harris County (principally in the Sims Bayou area). HCFCD estimated that of the 3,370 affected homes, ninety to ninety-five percent were flooded due to poor street drainage or from channel flooding by small tributaries. The June 19 event was the countys second largest flood based on the number of inundated homes. NFIP representatives i
Related Questions
- What are the flooding and debris flow impacts that could potentially occur after a fire? For how long after the fire am I facing the potential impacts?
- Do the floodplain management requirements apply to construction taking place outside the SFHAs within the community?
- Does flooding occur outside of a FEMA-mapped floodplain?
