State of the Bayou
Downed Trees. New Channel. New Riprap. Washed Out Sidewalks, Beavers, and Turtles
But Some Banks Naturally Rebuilding
Does It Make Sense to Repair?
Sept. 1, 2016
Updated Sept. 11, 2016
You could not step twice into the same river. Heraclitus
We finally had a chance recently to float down beautiful Buffalo Bayou to see how things have changed. Our trip took us past Memorial Park in the middle of Houston. We also biked along the bayou through Terry Hershey Park far upstream in west Houston below the dams to see what was happening there.
The good news is that some of the high banks that had slumped in Memorial Park and the Hogg Bird Sanctuary during the Memorial Day 2015 flooding are naturally rebuilding.
The bad news is that the River Oaks Country Club has added more riprap to the south bank, hard armoring the bank with ugly, damaging concrete rubble, including where it should not be.
Nature’s Miraculous Way of Restoring. For Free.
Houston has had multiple record-breaking rains and flooding since the spring of 2015. When Buffalo Bayou overflows its high banks, as it did in the Memorial Day flood of 2015, the banks in places sometimes slump or slide away. This happens when the overflowing water seeps through the ground and saturates layers of sandy clay that liquefy, sometimes causing the bank to give way. Buffalo Bayou is 18,000 years old, and this has been happening for a very long time.
This natural tendency to slump is one reason why we think attempting to engineer these banks as proposed by the $6 million Memorial Park Demonstration Project won’t work. It’s also the reason why we think building and repeatedly repairing sidewalks at the bayou’s edge is wasteful and foolish.
The south-facing high bank of the Hogg Bird Sanctuary collapsed during the Memorial Day flood in 2015. Now self-restored. Photo on August 4, 2016.
Can An Urban Stream Restore Itself?
Yes, With Room to Move. Free Rivers Are Healthier and Better for Flood Control
June 15, 2016
Updated with August 2016, April 29 and July 11, 2017, photos of self-repaired Hogg Bluff
By Susan Chadwick, Executive Director, Save Buffalo Bayou
This article is adapted from a presentation made at the Southwest Stream Restoration Conference in San Antonio, Texas, on June 2, 2016.
Save Buffalo Bayou is a non-profit organization founded two years ago to fight a public project described as a “restoration” project on one of the last natural stretches of Buffalo Bayou as it flows through the middle of Houston, past 1,500-acre Memorial Park and another 15-acre public nature preserve, the Hogg Bird Sanctuary. Since then our organization has expanded into broader, related issues. But today’s topic is restoration.
Here are some of the most common responses I would get when I would say that this mile-long plus stretch of the bayou is natural, along with what were some of the most common defenses of the project.
Sandy bank on a meander of Buffalo Bayou in Memorial Park. Photo by Jim Olive on April 2, 2016
The river’s not natural because the river changes.
It’s not natural because it’s been altered by high runoff from urbanization.
Trees fall into it.
It has terrible erosion problems. Look at those steep high banks!
It’s terribly eroded. Look at those sandy banks!
It’s eroding terribly. Sediment from the banks in Memorial Park washes up on the sidewalks of Buffalo Bayou Park we built downstream in the floodway right next to the river.
All that sediment carries bacteria. If we stop the banks from eroding so much sediment, we will reduce the bacteria. (Although sediment-laden Buffalo Bayou is less polluted than White Oak Bayou, which runs relatively clear and extremely foul due to being encased in concrete.)
And of course the big one: the river needs to be stabilized because it moves around.
Then there’s the argument, both implied and explicit, that prompted me to select this topic for presentation today: an urban stream cannot restore itself.
A Profound Misconception About How Nature and Rivers Work
All of those statements, of course, indicate a profound misconception about nature, about how a river works and how rivers benefit us.
A river is a living symbol of change. A living system. A dynamic process of nature that works for our benefit. Even the simple grains of sand work on our behalf to cleanse the water.
Recent Comments