Atchafalaya River ( English Atchafalaya River ) - the sleeve of the Mississippi and Red River deltas with a length of approximately 225 km, in southern Louisiana , USA [1] . The river is navigable and of great importance to the state. Supporting the river in appropriate condition has been provided by the corps of engineers of the US Army for more than a century.
| Atchafalaya | |
|---|---|
| English Atchafalaya river | |
 Atchafalaya Delta | |
| Characteristic | |
| Length | 225 km |
| Watercourse | |
| Source | Red river |
| • Coordinates | |
| Mouth | Gulf of Mexico |
| • Height | 0 m |
| • Coordinates | |
| Location | |
| Water system | Gulf of Mexico |
| A country |
|
| Region | Louisiana |
 - source  - mouth | |
Atchafalaya is formed from a natural channel at the confluence of the Mississippi and the Red River, called the Old River, 11 km long [1] . Further, the river continues its movement a little to the west of the main flow of the Mississippi and flows into the Gulf of Mexico about 25 km south of the city of Morgan City [2] .
Content
- 1 History
- 1.1 Old River Control Complex
- 2 See also
- 3 notes
- 4 References
History
Until the 15th century, the Mississippi and the Red River flowed parallel to each other, but then the Mississippi’s bed turned west, forming a bend (“Turnbull Bend”), which merged with the Red River. The Red River in the upper reaches became a tributary of the Mississippi, and the former lower reaches of the Red River - now a branch of the Mississippi - was called Atchafalaya [3] .
In the 1830s, under the guidance of the famous engineer Henry Shreve , the Great Raft was cleared - a huge congestion of fallen trees, which complicated the course of Atchafalaya and the Red River and made navigation impossible [4] . Shreve also dug a canal at the site of the former Mississippi channel. After that, the northern part of Turnbull Bend was filled with sedimentary rocks, while the southern Old River continued to connect the three rivers [3] .
A channel dug by Shreve changed the natural order of things. The flow of water from the Mississippi and Red River to Atchafalaya increased, and the river began to become wider and deeper [5] . Between 1850 and 1950, the outflow of water from the Mississippi to Atchafalaya increased from 10% to 30%. There was a threat that the Mississippi channel will change its course and flow into Atchafalaya, whose path to the ocean is 2 times shorter [6] .
Old River Control Complex
Since the 1950s, U.S. engineering forces have been building hydraulic structures to contain the flow of rivers in their beds, regulate and maintain the outflow of water from the Mississippi to Atchafalaya at the level of 30% and the controlled diversion of water to Atchafalaya during floods. The banks were strengthened , an additional outflow channel with a dam and spillway was dug upstream of the Old River, and the Old River was closed. In 1963, work to create the Old River Control Complex was completed [6] [7] .
In 1973, a massive flood on the Mississippi damaged the dam, almost collapsing it. The repairs performed could not fully restore its strength. An additional channel and facilities were created to distribute the load. A navigation gateway was installed on the Old River, and Atchafalaya became navigable again. In the mid-1980s, another hydroelectric power station was built on another canal connecting the Mississippi with the outflow channel [6] [7] .
See also
- Atchafalaya Pool
Notes
- ↑ 1 2 Atchafalaya River . Encyclopedia Britannica . Date of treatment February 4, 2019.
- ↑ Atchafalaya Delta . Louisiana Department of Wildlife and Fisheries . Date of treatment February 4, 2019.
- ↑ 1 2 Rivers & Flood Control (inaccessible link) . Atchafalaya National Heritage Area . Date of treatment February 4, 2019. Archived February 7, 2019.
- ↑ Great Raft History . InvasivesWatch.org . Date of treatment February 4, 2019.
- ↑ Article 612487 - No Title . The New York Times (3 May 1987). Date of treatment February 12, 2019.
- ↑ 1 2 3 Louisiana River Control . America's WETLAND: Resource Center (2012). Date of treatment February 12, 2019.
- ↑ 1 2 Old River Control Structure, Point Breeze, LA . John A. Weeks III . Date of treatment February 12, 2019.