In 2023, Harris County already knew the new maps would drastically increase how many homes and businesses fell within a likely flood zone. "The new 100-year will probably be close to the 500-year ...

1 foot of flooding is expected during a 500-yr flood. All occupants of the building should evacuate to the nearest Newton Court second level. Flood level expected to reach 1 foot during a 100-year ...

A 500-year flood means such an event has a 1 in 500 chance, or 0.2%, of occurring in a year. Another concept scientists use is how frequently an event of a certain intensity is expected.

Ithaca’s Common Council will vote to adopt new FEMA flood maps and update floodplain management ... would set the boundaries for the 100- and 500-year floodplains,” city Director of Planning ...