Temple University’s Flood Map Is Too Good

In 2002, Temple University began working on a flood map of the Pennypack Creek watershed, an area on the north side of Philadelphia that historically has been particularly prone to flooding. The resulting maps, the Philadelphia Inquirer reports in a special section on flooding, were, paradoxically, too good:

After seeing the finished product last month, the agency told Temple that there was a problem: The maps were too precise to be adopted by the federal government.
The researchers’ work was done in such exacting detail — literally house by house — that it was far and above FEMA’s longtime standards for floodplain mapping, said Martin Frengs, an official at the agency’s regional headquarters in Philadelphia. The maps’ quality, he explained, must be uniform across the country because they are the foundation of the National Flood Insurance Program, which FEMA administers.
Temple’s renditions would be Michelangelos in a Grandma Moses gallery.

The Inquirer shows the differences in detail between Temple’s and FEMA’s maps on this interactive map. Via MapHist.