Bulldozed by Flood Control, Here’s How Bare Dirt Banks Fared After Storm Beta
Oct. 7, 2020
After nearly two weeks of high flow in Buffalo Bayou, the Corps of Engineers on Tuesday, Oct. 6, finally finished emptying stormwater from Tropical Storm Beta impounded behind Barker and Addicks dams in west Houston. So we went out to look at how the once-healthy banks had fared in Buffalo Bayou Park between Allen Parkway and Memorial Drive.
These particular banks, three stretches upstream of the Waugh Bridge, had been naturally planted by the river’s eastward flow with deep-rooted native horseweed, goldenrod, and young willows, among other vegetation. Recently they had been stripped and graded by the Harris County Flood Control District as part of the district’s overall $9.7 million project to “repair” banks, mostly by dumping and pounding concrete riprap, in the popular park damaged by Hurricane Harvey in 2017.
Flood Control managed to bulldoze these apparently stable upstream banks just in time for Beta, which in 24 hours dropped more than 11 inches of rain in places within the bayou watershed, finishing up in the early morning of Sept. 23.
Even with the dam floodgates closed, the bayou downstream flooded, swollen with rainwater running off the city’s roofs, streets, driveways, and parking lots and through drainage pipes. The US Geological Survey gauge at Piney Point measured a flow of some 7,000 cubic feet per second (cfs), increasing downstream to some 12,000 cfs at Shepherd Drive, well above flood stage in both cases.
When the Piney Point gauge fell below 3,000 cfs on Sept. 23, the Corps of Engineers opened the dam gates in order to empty the reservoirs that had filled with stormwater flowing from streams and creeks fed by rain running off developments, roads, and shopping malls further west and north.
Here is what the denuded banks in Buffalo Bayou Park looked like on Oct.7 after the flow in the bayou dropped to near normal flow: