Springtime on Buffalo Bayou
Through the Woods on a Brilliant Sunday Morning
April 19, 2018
At last spring had sprung. The trees were bursting with joyous green, celebrating by tossing enormous amounts of pollen into the air. Time for our seasonal photograph of that Bend in the River. Our dedicated photographer Jim Olive was preoccupied with saguaro cacti in California, so it was up to a couple of lesser talents to document Spring 2018 on Buffalo Bayou.
We set off from the small parking lot on the South Picnic Loop in Memorial Park and headed down the path into the woods. The sunlight sparkled through the trees, though some of our old friends had fallen, lying now against the slumped bank. The bayou, now visible through those that remained, was closer. Flow was about 650 cubic feet per second after a brief thunderstorm the day before. The dirt path was soft. We were delighted to see that the high bank in the park that had been damaged and defaced by the unauthorized installation of a rogue mountain bike jump has healed. The wooden jump that had been pounded into the very edge of the bank has been removed, and only a few holes remained.
The last time we had walked in these woods the rolling landscape, carved by ravines, was brown, muddy, monotone, and empty. The trees were skeletal. Winter can be frightening that way, especially in a city so badly hurt by an unprecedented flood. Would life return?
But now the banks that had slumped during the high waters from Harvey appeared to be healing. There was still little ground cover on the slopes of the small tributary that drains the center of the park, and the winding path of the tributary was much changed. One could now see from the shallow creek over the diminished bank of the bayou towards the distant golf course on the south bank far downstream, stripped of trees and vegetation years ago and now covered in plastic sheeting by the River Oaks Country Club.
Elsewhere the bayou was renewing itself, adjusting to our changing climate. Here is the Bend in the River that we have been documenting through the seasons for the last four years. You can see the entire series here.
And here is a photo looking upstream from the same high bank in Memorial Park.
Why “Improving Conveyance” Doesn’t Work
It Causes More Flooding
Taming the Mighty Mississippi May Have Caused Bigger Floods
Human meddling with the river is blamed for most of the rise in flood levels, but the role of climate remains unclear
Now a new study raises the possibility much of the effort humans have put into trying to control the mighty river has paradoxically made its large floods more destructive. The magnitude of so-called 100-year floods—massive inundations defined as having a 1 percent chance of occurring in any given year—has increased 20 percent in the past five centuries on the lower Mississippi, researchers reported this month in Nature. The bulk of the increase has been in the last 150 years, when human engineering of the river has been most intense. “We’ve channelized the river, we’ve straightened it,” says Samuel Muñoz, lead author of the new study and an assistant professor of marine and environmental sciences at Northeastern University. “We’ve made the gradient steeper, and we’ve encased the river in concrete mats and lined it with levees.”
The resulting physics is straightforward, Muñoz explains. With little leeway to meander and limited floodplain to spread over, the waters of the Mississippi in places are corralled into a relatively narrow chute, making peak flows higher than they would be otherwise. Muñoz and his colleagues estimate about 75 percent of the increase in 100-year-flood magnitude is due to river engineering, with the rest attributable to natural climate cycles. The study was not able to factor in the influence of anthropogenic climate change effects, though, leaving open the question of how much rising flood levels are driven by engineering and how much by a warming climate.
Read the rest of this article in Scientific American.