New research funded by the UNC Collaboratory revealed that 90,000 buildings have experienced flooding over 24 years, some repetitively.

FEMA is anticipated to open a 90-day public appeal and comment period in the winter where property owners can formally challenge the flood zone designation but they must provide scientific or technical data to back up their request.

While FEMA has improved the accuracy and accessibility of the maps over time with better data, digital tools and community input, the maps still don't capture everything.

Climate change is increasing the risk of dangerous floods. But people often balk at the cost of flood insurance, especially since many doubt they need protection.

At least 27 campers and counselors at Camp Mystic perished in Friday's floods, with the total death toll in the floods now surpassing 100.

The risk of the catastrophic flooding that struck Texas Hill Country as people slept on July 4 and left at least 120 dead was potentially underestimated by federal authorities, according to an ABC News analysis of Federal Emergency Management Agency data, satellite imagery and risk modeling.