The Flood Control District’s Failing “Natural Channel Design” Projects
July 11, 2015
Well, the comments are in to the Army Corps of Engineers. The comment period that ended June 5 was not extended. So now we wait to find out what the Corps will do next about a permit for the Harris County Flood Control District’s controversial $6 million Memorial Park Demonstration Project. The flood control district wants to destroy one of the last natural stretches of Buffalo Bayou as it flows past Memorial Park in the middle of the city so that engineers can “build it better,” thus demonstrating exactly the wrong thing to do for erosion control and bank stabilization on the bayou.
It’s the wrong thing to do because the specially adapted trees and plants on the bayou (known as the riparian zone) protect the land from erosion, slow storm water and runoff, filter pollution and bacteria (and trash) from the water, provide shade and habitat, among many other vital functions. Razing the riparian buffer, as this project would do, digging up and running heavy equipment over the banks and bayou bottom are all contrary to Best Management Practices and the policies of virtually every federal and state agency charged with protecting the health of our waters, our wildlife habitat, and our soil.
What Are the Options?
So what are the Corps’ options? The Corps could deny the permit. (Never happens like that.) The Corps could decide to hold a public hearing. (Unlikely: they’ve already received hundreds of public comments, the vast majority negative.) The Corps could decide that the purpose of this project was not clear (true) and that the environmental impact of the project was not clear (true, although rational people see that the impact would be damaging). In that event the Corps could declare the project an “environmental controversy” and require an environmental impact assessment.
We believe there are strong grounds for requiring an environmental impact statement.
The Corps could also approve the permit. That decision would have to be appealed in federal court. To stop the bulldozers, we would have to file for an injunction. That will take money, so please press the Donate button now. We’ll give you a free bumper sticker.
Failing “Natural Channel Design” Flood Control Projects in Harris County
The flood control district describes the Memorial Park project as “natural channel design,” which is a term that apparently has come to mean just about any channelizing project that doesn’t include concrete but does include curves. Natural channel design has a history of failed and washed out projects, and we believe this controversial and destructive method proposed for Memorial Park has a risk for failure also. Let us look at the success of a couple of the district’s previous “natural channel design” projects.
Buffalo Bayou Park
Even in its recent “revised” but essentially unchanged permit application, the district continues to tout its “natural stable channel design” project in Buffalo Bayou Park between Shepherd Drive and Sabine Street downstream from Memorial Park. This is the most prominent of the district’s “natural channel design” or “natural stable channel design” projects (see page 30). (At some point the district added the word “stable” to the “NCD” description, “natural channel design” being a term invented and possibly trademarked by the controversial river guru, Dave Rosgen, a founding father of the lucrative river “restoration” industry.)
However, few people know this popular and nearly finished $58 million park between Allen Parkway and Memorial Drive is also a flood control district project. The nationally-recognized park is best known as a model of urban design, with scenic concrete and asphalt walking, biking, and running trails, and much-needed recreational facilities for people and dogs. And indeed some parts are lovely, if you can get there and find a parking space.
In 2012 the flood control district began working on a $5 million program to “restore” the two-mile stretch of the bayou between Sabine and Shepherd. The district removed trees and plants, bulldozed, scraped, and graded the banks, dredged and realigned the channel, destabilizing the riparian zone, although destabilization was not the plan.
Since then the park has been suffering from sinkholes, massive and accelerated erosion, undercutting, collapsing banks, major tree loss, and more, even before being inundated by the recent Memorial Day flood.
Save Buffalo Bayou commissioned landscape ecologist Tom Hayes of the Environmental Conservation Alliance to prepare a report on this natural stable channel design “demonstration project” in Buffalo Bayou Park, a report sent to the Army Corps of Engineers. On a survey trip by canoe through the park last February, Hayes, observing the repeated futile attempts to repair eroding banks, commented that “they should just quit now.” Let the bayou naturally rebuild and replant. Which is what the bayou is already doing there in places.
Here is Hayes’ conclusion as written in the report sent to the Corps:
“Due to the apparent multiple failures of the prior demonstration project [Buffalo Bayou Park] as discussed in this report and elsewhere, the next phase of the project proposed for Memorial Park should not be permitted. The unchannelized bayou within this public park [Memorial Park] currently contributes minimal sedimentation compared to the actively eroding condition produced by recent channelization. There is no reason to dredge the channel, destabilize the banks, and continue to remove the riparian forest, when the results of the present demonstration project have been increased erosion and downstream sedimentation, and destruction of vital ecosystem and community services.”
Watch a slide show of Buffalo Bayou between Shepherd Drive and Sabine Street before and after the flood control district’s “natural stable channel design” project:
Big Gulch/Fonteno Park
Another failed flood control project, initially described as “natural channel design” but now unmentioned by the district, is the $1.05 million plus $200,000 or so Big Gulch project on a tributary of Greens Bayou adjacent to Fonteno Park and two public schools in northeast Harris County.
As announced by the flood control district in July 2014, “stormwater runoff has severely eroded the tributary’s streambanks and channel bottom, causing trees to fall into the creek and an excessive amount of sediment to be deposited into the waterway. The erosion and tree loss affects the District’s ability to maintain the system and can adversely affect flooding. Sediment deposition also impacts water quality and aquatic habitat, which affects fish and other aquatic life.
“The overall goal of the project is to restore the stream banks and channel bottom to a stable condition using natural channel design techniques, while introducing water quality enhancement features to improve stormwater quality and to protect aquatic habitat.”
The result has been a disaster. Geologist Richard Hyde has been documenting this catastrophe for several months. The flood control district bulldozed a large amount of riparian vegetation and forest, including mature, tall trees. Hyde reports on the results. What follows is a slide show of his annotated photographs from May 2015 and earlier. The text in gray is from the flood control district’s description of the project.