It is said that history doesn’t repeat itself, but it does mimic itself. The same can be said for tropical cyclones. While each storm is unique, there are enough commonalities that we can learn from them.
I will look at three systems (Tropical Storm Claudette, July, 1979; Tropical Storm Allison, June, 2001 and of course, Hurricane Harvey) and see what lessons we can draw from these events.
Tropical Storm Claudette (1979)
Tropical Storm Claudette moved ashore near Sabine Pass, turned west and then drifted around the north side of Houston for a couple of days before finally moving off to the north. It set the (then) national record for rainfall in a single event with nearly 45 inches of rain near Alvin. 15,000 homes and 17,000 vehicles were damaged in the storm in Galveston County, which saw Clear Creek rise 9 feet and expand to more than a mile in width.
Tropical Storm Allison (2001)
Tropical Storm Allison came ashore southwest of Galveston, headed due north, then turned west and south moving offshore southwest of Freeport and then headed east. Days of rain produced 35 inches of rain in northeast Houston and 40 inches near Beaumont. In Harris County alone, there were 22 fatalities, 95,000 damaged automobiles and trucks, 73,000 damaged residences, 30,000 residents in shelters and more than $5 billion in property damage.
Hurricane Harvey (2017)
Hurricane Harvey made landfall near Port Aransas as a Category 4 hurricane with 140-mph sustained winds. It then tracked inland past Victoria, stalled and then moved back southeast off the Texas coast near Matagorda as a tropical storm. The large, wet system then drifted north to just east of Galveston before tracking off to the northeast into Louisiana and the South. A storm total of 51.88 inches near Cedar Bayou set a new national record, while rains of 49 inches at Clear Creek and I-45, 43 inches at League City/Dickinson and 22-28 inches on Galveston Island led to widespread flooding over much of Galveston and surrounding counties.
Lessons from these storms
1. It will happen again. With development over flood-prone areas decreasing the overall acreage available to absorb rainfall and increasing runoff, such flooding is inevitable whenever a slow-moving, large wet system moves inland along the coast.
2. In each of these storms, residents said that they did not have flood insurance because they had never flooded before or where not in a flood zone. The bottom line is that anyone who lives in Southeast Texas is at risk for flooding and should have insurance to provide for that eventuality.
3. We need to work on regional intra-structure to minimize such flooding as much as humanely possible. Much of our intra-structure is outdated and designed to manage either lesser storms or was build before development changed the inflows they were created to manage.
4. Rebuilding efforts and new development should focus on built in resilience, raising structures as well as protecting electrical and other utility systems. Codes need to be created and enforced that protect new structures against both wind and flood dangers.
5. While individual efforts, as well as volunteer assistance, is vital to both preparing and planning for the next storm, as well as ensuring safety during storms, it is clear that it will take the combined efforts of the private sector, local communities, states and the federal government to really address a problem larger than any one group can manage. Such storms do not respect individual, political or geographic boundaries. It will require a cooperative effort to adequately ensure our future on the Gulf Coast.