Jim Bradshaw: When mighty Atchafalaya was just a trickle of a river

Today we know the Atchafalaya as a river that is swift, strong, deep, and sometimes treacherous.
But it wasn’t anything like the modern stream until the middle 1800s. The main reason for that was a huge raft of logs that choked the river near its head and for 20 or more miles downriver.
Even that first little stream evolved relatively late as geologists count things, about 1,500 years ago.
A study done by the Corps of Engineers in the 1950s (Geological Investigation of the Atchafalaya Basin and the Problem of Mississippi River Diversion, April 1952) points out that the Atchafalaya Basin was formed by a depression left behind as the Mississippi River meandered for centuries across south Louisiana.
“The entire southern basin area as far north as the latitude of Baton Rouge was one large lake,” according to that study.
Fossils found beneath that long-gone lake show that it was a bit salty because water from the Gulf flowed into it from time to time.
The lake apparently narrowed at its southern end, forming something like a river, but it didn’t reach very far inland.
The Atchafalaya River began to form in the Basin about 1500 A.D., according to the study. A map drawn in 1578, when Hernando DeSoto and his band straggled through Louisiana, shows its beginnings as a tributary of the Mississippi.
This was well before Europeans came to Louisiana to settle, and “the absence of Indian mounds along its course” seem to indicate that nobody settled along its banks during its infancy.
Indeed, the report finds, “Accounts of later visitors to the Atchafalaya Basin reflect its impassability.”
The study points out that “highly cultivated and well-populated communities quickly developed on the … ridges of the Teche and Lafourche, but no overland trails of any consequence crossed the basin; only water transportation was feasible.” Even then, the Atchafalaya River remained “a minor stream, choked by a raft of logs at its upper end.”
Geographer William Darby described that raft in 1816 as a “mass of timber that rises and falls with the water in the river, and at all seasons maintains an equal elevation above the surface.”
But, he said, stories that logs were so thickly piled together that horses could be ridden across them were “entirely void of truth.”
It could have been that they would support a man walking across them, at least during some parts of the year. In 1839, planters wanting to establish steamboat navigation on the river, “availing themselves of one of the seasons of greatest drought, … set fire to the raft,” according to a contemporary account.
The fire “swept over the raft, some twenty miles in extent, destroying thousands of alligators and burning off the immense mass of timber to the water’s edge, but it did not remove the raft below the water.”
According to that account, “The water in 1839 was so low that foot passengers, by means of a plank 15 feet long, could walk across the river.”
The state used tugboats to clear the underwater logs in 1840 “to the extent needed for steamboat travel,” but only seven years later engineers reported that the stream was again filled with logs “from a point two miles above Bayou Pigeon to within seven miles of its head.”
Tugs went in regularly for the next few years and most of the debris was finally removed about 1850.
After that, according to a Mississippi River Commission report written in 1881, the river’s “rapid enlargement commenced.”
According to the commission report, “Portions of the raft that had been left … were washed out piecemeal” and the increased flow began to scour and deepen the river bed.
But the planters should have been careful about what they prayed for.
The deeper river made for better the steamboat navigation they wanted, but it also played havoc with their land and their bank accounts.
“Lands previously exempt from overflow were annually submerged by the increasing volume,” according to the 1881 account.
“First the profits and then the capital of the owners was absorbed in building and raising levees.”
It finally proved too costly. River waters ate away planters’ land and fortunes and gave them no choice but “the general abandonment of this naturally favored region to the hunter and the raftsman.”
A collection of Jim Bradshaw’s columns, "Cajuns and Other Characters," is now available from Pelican Publishing. You can contact him at jimbradshaw4321@gmail.com or P.O. Box 1121, Washington LA 70589.