If that estimate holds, it would make Harvey the world's 9th most expensive natural disaster since 1900.
If that estimate holds, it would make Harvey the world's 9th most expensive natural disaster since 1900, according to the Center for Disaster Management and Risk Reduction Technology (CEDIM) in Karlsruhe, Germany.
It would also push the yearly economic loss from earthquakes, floods, tsunamis, cyclones and other natural cataclysms past $100 billion for the 8th year in a row.
"The damage is extensive at around $58 billion, and is over 90 percent due to flooding," said James Daniell, senior risk engineer at CEDIM, and head of its Forensic Disaster Analysis Group.
The estimate carries uncertainty range from $41 billion to $80 billion.
"Depending on the next couple of days, we may see this estimate rise, as it only includes Texas at this point," he told AFP.
The total "flooded exposure" -- the value of all the capital stock inundated by water, whether five centimetres or five metres -- in the affected area was estimated at $267 billion.
Other calculations of total economic loss have been considerably lower.
German insurance giant Hannover Re's initial figure for damages was $3 billion, while JP Morgan estimated the insurance sector could be out $10-20 billion.
Disaster risk specialists Enki Holdings, based in Savannah, Georgia, put the total tab at above $30 billion.
The CEDIM estimates are based in part on the largest database of natural catastrophes in the world, covering over 41,000 events since 1900.
They also reviewed new TerraSAR-X satellite data, which indicates a flood "footprint."
To measure the region's risk exposure, Daniell and his team used data from the US Bureau of Economic Analysis, which tracks investment.
"But we also checked that against building and replacement cost data," Daniell said. "That's usually the issue with a lot of other models -- they don't get the exposure right."
Total capital stock in Texas is about $4.5 trillion, and for the entire United States the figure is about $56 trillion, he said.
The natural disaster with the highest economic costs -- $218 billion was the 2011 Tohoku earthquake, which generated a monster tsunami that devastated a large swathe of Honshu Island and crippled a nuclear power plant.
In second place is the earthquake that levelled part of China's Sichuan Province in 2008 ($162 billion), followed by Hurricane Katrina, which destroyed much of New Orleans in 2005 ($160 billion).
CEDIM's detailed report on Hurricane Harvey's impact on Houston can be found at: http://www.cedim.de/download/FDA_Harvey_2017_report1.pdf.