(Reuters) – At least $23 billion worth of property has been affected by flooding from Hurricane Harvey just in parts of Texas’ Harris and Galveston counties, a Reuters analysis of satellite imagery and property data shows.
The number represents market value, not storm damage, and is but a small fraction of the storm’s reach, as satellite images of the flooding are incomplete. Satellite imagery compiled by researchers at the University of Colorado shows flooding across 234 square miles (600 sq km)of Harris County and 51 square miles (132 sq km) of Galveston County, about one-eighth of each county’s land area.
(For a map of flooding caused by Hurricane Harvey click tmsnrt.rs/2erCMUT)
It is impossible to discern damage amounts from the data, as the satellite imagery does not reveal the depth of the floodwaters; nor does it reveal the impact of wind. But even this partial tally signals that the storm will rank among the most damaging in U.S. history.
Reuters overlaid the flood imagery on property parcel maps and found floodwaters had encroached on at least 30,000 properties in the two counties, with a total market value of $23.4 billion.
Of that, 26 percent is land value; the rest is buildings and other improvements. In Harris County, where Reuters was able to determine the property’s use, about 18 percent of the affected property is residential.
The tally omits much of Houston’s dense urban center because a satellite specializing in urban imagery has not yet taken enough images there. Floodwaters have inundated the area, like surrounding regions, and thousands of homes are damaged. Many roads, including vital highways and parkways, were submerged and businesses flooded and shuttered.
Ultimately, storm damage totals will come from estimates of insured and uninsured losses and disaster assistance payments, not from tallying property assessment values.
And real estate is only part of the equation in the rapidly rising toll as Harvey moves from Texas to Louisiana. Federal damage estimates will also include the vast cost of business interruptions, ruined vehicles and other personal possessions, repairs to roadways and other public infrastructure, and disaster aid like the money used to feed and house tens of thousands of displaced people.
Adam Smith, a lead scientist for the federal agency that compiles storm damage costs, said it is “very possible” Harvey’s costs may surpass the record $160 billion from Hurricane Katrina.
“But it will take some time…