Virtual Public Meeting Tuesday, Oct. 13. Comment Period Now
Oct. 13, 2020
The US Army Corps of Engineers has come up with an outrageous plan to strip, deepen and widen Buffalo Bayou and line it in places with concrete block for 22-24 miles all the way from Highway 6 in far west Houston to 1,500-feet downstream of Montrose in Buffalo Bayou Park downtown.
Is this the 1930’s? The 1960’s? The plan is so backwards and outdated it’s difficult to believe they are serious.
The Corps even admits the project could kill all aquatic life in the bayou. (p. 178-180) And that there are no positive net benefits. (pp. 19 and 149) The cost is estimated to be from $1 billion to $4 billion, not including future continuing maintenance.
Modern flood risk management focuses on stopping stormwaters before they flood streams. On managing flooding in place, stopping raindrops where they fall, on slowing down, spreading out, and soaking in rainfall. And getting out of the way. Sponge cities. Green infrastructure. Wetlands, greenspace, trees. Both the City of Houston and Harris County have emphasized this, as have cities around the state and around the world.
Creating capacity to convey more and faster rainwater runoff encourages the production of more and faster runoff. As the excellent Greater Houston Flood Mitigation Consortium reported in 2018, “conveyance projects can make flooding worse.” (p. 17)
Note that Harris County Flood Control just spent nearly $10 million reconfiguring the banks in Buffalo Bayou Park downtown. (See here and here.) In 2017 the agency also spent millions “repairing” the north bank in Terry Hershey Park between Beltway 8 and Highway 6, and in 2019 spent millions more clearing trees and scraping shallow detention basins out of the park’s south bank.
Also note the Corps’ report complains that in places the bayou is naturally deepening and widening itself (p. 67-68) and this problem will have to be fixed. But at the same time the bayou needs to be deeper and wider so we are going to do that with bulldozers and billions of dollars.
Attend a Virtual Public Meeting, Send Comments
The Corps is holding virtual public meetings on the report, known as the Buffalo Bayou and Tributaries Resiliency Study Interim Feasibility Report. The first virtual meeting is today, Tuesday, Oct. 13, from 6 to 8 p.m., followed by meetings on Oct. 15, 22, and 26. Here is how to join the meetings.
The public comment period opened Oct. 2 when the Corps’ Galveston District released the 210-page report. Public comment ends on Nov. 2. Here is how to send your comments to the Corps.
Purpose and Alternatives
The purpose of the study is to figure out what to do about too much stormwater flowing too fast into Addicks and Barker reservoirs, the flood control dams in far west Houston that drain into Buffalo Bayou. (Note that the Harris County Flood Control District has been busy speeding up the flow of stormwater through tributary streams into Addicks and Barker reservoirs.)
Numerous ideas were analyzed by the Corps’ team, including doing nothing, building new dams, increasing the capacity of the existing reservoirs, removing the dams, raising the dams, digging large flood tunnels from Barker reservoir to the Houston ship channel or Galveston Bay, the Brazos River or Brays Bayou, and more.
Virtually all of those proposals cause massive ecological, environmental, and societal damage, including the loss of schools and homes, closure of businesses, reduction in revenue and services, and more. (pp. 175-183)
The top rated proposal from the engineers was non-structural: buyout homes and businesses in the floodplain below the dams. (p. 149) But they like doing this in combination with bulldozing and armoring virtually the entire bayou west of downtown.
The idea is to increase the capacity of the bayou to carry 15,000 cubic feet per second (cfs) without flooding anyone below the dams, except possibly downtown, so that they can empty the reservoirs faster and save neighborhoods behind the dams, as well as the dams themselves. The study’s authors anticipate that the region beyond the dams will continue developing, creating more and faster runoff, and that rainstorms will continue to increase in intensity and frequency. (p. 7)
To increase bayou capacity they would widen the top of the bayou channel to 230 feet, the channel bottom to 70 feet, the average depth to 11.6 feet, laying back the banks, including the bayou’s historic high cliffs if necessary (p. 18), some of which have been laying back anyway.
During Hurricane Harvey in 2017, the normally empty park-like reservoirs filled up and began backing up and flooding homes built in and near the reservoir pools, on land that the federal government was supposed to buy but didn’t. Naturally developers moved in.
Then the unprecedented high water level behind the dams threatened to spill around the dams or even overtop the dams, a scenario so potentially disastrous that the Corps began releasing water from the dams in the very early morning of Aug. 28, 2017. A few hours later stormwater did spill around the northern end of Addicks Dam, which, as noted in the report, had subsided three feet. (p. 46) Both of the reservoirs have subsided. (p. 69)
The peak of Harvey flooding had already passed downstream on Aug. 27, when the dam floodgates were closed. This downstream flooding was the result of rainwater running quickly off the paved and built surface of the city below the dams. (There was also substantial flooding from streets and yards that could not drain into the bayou. Stormwater pipes were blocked or even flowing back into neighborhoods because of the high water level of the bayou.)
Peak flow at Beltway 8 during Harvey was almost 23,000 cfs on Aug. 31, 2017, though there was some doubt about whether the gauges were working properly during the massive flood. The Corps operates the dams on the basis that homes downstream can start to flood when the Piney Point gauge hits 4,000 cfs.
The fact that downstream floods even when the dam floodgates are closed is why building a flood tunnel to carry water from Barker Reservoir to the Houston Ship Channel or Galveston Bay, the Brazos River or Brays Bayou, is not necessarily going to prevent anyone downstream of the dams from flooding. The report dismisses the flood tunnel ideas for a variety of good reasons. (pp. 106-110)
The opening of the floodgates badly flooded thousands of residences and businesses in neighborhoods around and upstream of Beltway 8, along the 6-mile long stretch of the bayou flowing through Terry Hershey Park. This stretch of the bayou immediately below the dams was channelized, straightened and narrowed by the Corps in the 1950s.
It is in this area presumably that the Corps suggests buying out homes and businesses, though the report suggests buyouts through three unspecified reaches. (p. 117)
Also unspecified is how the Corps proposes to acquire the right-of-way necessary to widen Buffalo Bayou, the upper banks of which are largely privately owned.