page_title: Louisiana
section_title: Geography
hierarchical_section_title: Louisiana / Geography
caption_attribution_description: Oak tree all by itself in a field of yellow wildflowers near Violet, Louisiana
context_page_description: Louisiana is a state in the Deep South region of the South Central United States. It is the 19th-smallest by area and the 25th most populous of the 50 U.S. states. Louisiana is bordered by the state of Texas to the west, Arkansas to the north, Mississippi to the east, and the Gulf of Mexico to the south. A large part of its eastern boundary is demarcated by the Mississippi River. Louisiana is the only U.S. state with political subdivisions termed parishes, which are equivalent to counties. The state's capital is Baton Rouge, and its largest city is New Orleans.
  Much of the state's lands were formed from sediment washed down the Mississippi River, leaving enormous deltas and vast areas of coastal marsh and swamp. These contain a rich southern biota; typical examples include birds such as ibis and egrets. There are also many species of tree frogs, and fish such as sturgeon and paddlefish. In more elevated areas, fire is a natural process in the landscape and has produced extensive areas of longleaf pine forest and wet savannas. These support an exceptionally large number of plant species, including many species of terrestrial orchids and carnivorous plants.
context_section_description: Louisiana is bordered to the west by Texas; to the north by Arkansas; to the east by Mississippi; and to the south by the Gulf of Mexico.
  The state may properly be divided into two parts, the uplands of the north, and the alluvial along the coast. The alluvial region includes low swamp lands, coastal marshlands and beaches, and barrier islands that cover about 20,000 square miles (52,000 km²). This area lies principally along the Gulf of Mexico and the Mississippi River, which traverses the state from north to south for a distance of about 600 mi (970 km) and empties into the Gulf of Mexico; the Red River; the Ouachita River and its branches; and other minor streams (some of which are called bayous).
  The breadth of the alluvial region along the Mississippi is from 10 to 60 miles (15 to 100 km), and along the other rivers, the alluvial region averages about 10 miles (15 km) across. The Mississippi River flows along a ridge formed by its natural deposits (known as a levee), from which the lands decline toward a river beyond at an average fall of six feet per mile (3 m/km). The alluvial lands along other streams present similar features.
  The higher and contiguous hill lands of the north and northwestern part of the state have an area of more than 25,000 square miles (65,000 km²). They consist of prairie and woodlands. The elevations above sea level range from 10 feet (3 m) at the coast and swamp lands to 50 and 60 feet (15–18 m) at the prairie and alluvial lands. In the uplands and hills, the elevations rise to Driskill Mountain, the highest point in the state only 535 feet (163 m) above sea level. From 1932 to 2010 the state lost 1,800 square miles due to rises in sea level and erosion. The Louisiana Coastal Protection and Restoration Authority (CPRA) spends around $1 billion per year to help shore up and protect Louisiana shoreline and land in both federal and state funding.
  Besides the waterways already named, there are the Sabine, forming the western boundary; and the Pearl, the eastern boundary; the Calcasieu, the Mermentau, the Vermilion, Bayou Teche, the Atchafalaya, the Boeuf, Bayou Lafourche, the Courtableau River, Bayou D'Arbonne, the Macon River, the Tensas, Amite River, the Tchefuncte, the Tickfaw, the Natalbany River, and a number of other smaller streams, constituting a natural system of navigable waterways, aggregating over 4,000 miles (6,400 km) long.
  The state also has political jurisdiction over the approximately 3-mile (4.8 km)-wide portion of subsea land of the inner continental shelf in the Gulf of Mexico. Through a peculiarity of the political geography of the United States, this is substantially less than the 9-mile (14 km)-wide jurisdiction of nearby states Texas and Florida, which, like Louisiana, have extensive Gulf coastlines.
  The southern coast of Louisiana in the United States is among the fastest-disappearing areas in the world. This has largely resulted from human mismanagement of the coast (see Wetlands of Louisiana). At one time, the land was added to when spring floods from the Mississippi River added sediment and stimulated marsh growth; the land is now shrinking. There are multiple causes.
  Artificial levees block spring flood water that would bring fresh water and sediment to marshes. Swamps have been extensively logged, leaving canals and ditches that allow salt water to move inland. Canals dug for the oil and gas industry also allow storms to move sea water inland, where it damages swamps and marshes. Rising sea waters have exacerbated the problem. Some researchers estimate that the state is losing a landmass equivalent to 30 football fields every day. There are many proposals to save coastal areas by reducing human damage, including restoring natural floods from the Mississippi. Without such restoration, coastal communities will continue to disappear. And as the communities disappear, more and more people are leaving the region. Since the coastal wetlands support an economically important coastal fishery, the loss of wetlands is adversely affecting this industry.
caption: A field of yellow wildflowers in St. Bernard Parish
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