The late, great Stevie Ray Vaughan may have had an event like tropical storm Harvey in mind when he wrote “Texas Flood:”
Well dark clouds are rollin’ in
Man I’m standin’ out in the rain
Yeah flood water keep a rollin’
Man it’s about to drive poor me insane
That could well be the feeling among millions of Texas residents who have been hammered by the storm that still threatens to dump another 20 or more inches of rain on Houston and other cities in Harvey’s path. The amount of rain is so great that water held behind two flood control dams had to be released in order to prevent the dams from reaching the point of failure. The Houston Chronicle reported that “several thousand homes” are in a voluntary evacuation zone around the Addicks and Barker reservoirs.
These dams were designed and built to protect downtown Houston, and a meteorologist for the Harris County Flood control district told residents last night, “When the sun comes up, get out.”
About 20 miles north of Houston, the city of Conroe has ordered the evacuation of about 200 homes due to water releases from Lake Conroe Dam, a water supply reservoir that serves Houston and Conroe.
Analysts at CoreLogic have estimated that about 1.21 million properties in the Houston area are at “high” or “moderate” risk of flooding due to the volume of rainfall. Inside the FEMA-designated special flood hazard area (SFHA), 57,000 Houston metro homes are ranked at “extreme risk” and another 212,000 are labeled as “very high risk.” Nearly half a million properties in the Houston metro area outside the SFHA zones are at high risk and another 715,000 are at moderate risk of flooding.
Properties within SFHA zones, categorized as “extreme” or “very high” risk, require flood insurance if the property has a federally insured mortgage. Properties outside SFHA zones are not required to carry flood insurance.
All told, in the Houston area, about 63% of all properties both inside and outside SFHA zones are at greater than moderate risk of damage.
The Beaumont-Port Arthur metro has nearly 22,000 properties at extreme risk in the SFHA zones, and more than 100,000 outside the zones at either high or moderate risk levels. That is more than 60% of all 195,000 properties in the metro area.