Interstate 12 (I-12) is an intrastate
Interstate Highway
The Dwight D. Eisenhower National System of Interstate and Defense Highways, commonly known as the Interstate Highway System, or the Eisenhower Interstate System, is a network of controlled-access highways that forms part of the National Hi ...
located entirely within the
US state
In the United States, a state is a constituent political entity, of which there are 50. Bound together in a political union, each state holds governmental jurisdiction over a separate and defined geographic territory where it shares its so ...
of
Louisiana
Louisiana ( ; ; ) is a state in the Deep South and South Central regions of the United States. It borders Texas to the west, Arkansas to the north, and Mississippi to the east. Of the 50 U.S. states, it ranks 31st in area and 25 ...
. It spans a total of
in an east–west direction from
I-10 in
Baton Rouge
Baton Rouge ( ; , ) is the List of capitals in the United States, capital city of the U.S. state of Louisiana. It had a population of 227,470 at the 2020 United States census, making it List of municipalities in Louisiana, Louisiana's second-m ...
to an interchange with both I-10 and
I-59 in
Slidell. Along the way, it passes through the city of
Hammond, where it intersects
I-55 and
US Route 51 (US 51). It also serves the cities of
Ponchatoula and
Denham Springs, as well as the
St. Tammany Parish cities of
Covington and
Mandeville.
I-12 parallels the older
US 190 corridor and traverses the north shore of
Lake Pontchartrain
Lake Pontchartrain ( ; ) is an estuary located in southeastern Louisiana in the United States. It covers an area of with an average depth of . Some shipping channels are kept deeper through dredging. It is roughly oval in shape, about from w ...
in the southeastern portion of the state. The Interstate's length is
short for a mainline Interstate and is comparable with the country's longest
auxiliary Interstates. It is one of the shortest mainline Interstates to terminate at the same route (I-10) at either end. Apart from serving the various communities of the
North Shore, I-12 acts as a long
bypass of New Orleans and is heavily used as a shortcut for through traffic on I-10. While I-10 curves to the south to pass through the city limits, I-12 takes a more direct alignment, reducing the distance between Baton Rouge and Slidell by about .
In 1993, the
Louisiana State Legislature
The Louisiana State Legislature (; ) is the state legislature (United States), state legislature of the U.S. state of Louisiana. It is a bicameral legislature, body, comprising the lower house, the Louisiana House of Representatives with 105 ...
designated I-12 as the Republic of West Florida Parkway. In 2003, signs identifying the highway's official name and bearing the flag of the
Republic of West Florida
The Republic of West Florida (, ), officially the State of Florida, was a short-lived unrecognized republic in the western region of Spanish West Florida for just over months during 1810. In December, 1810, the United States occupied and an ...
were erected by the
Louisiana Department of Transportation and Development
The Louisiana Department of Transportation and Development (DOTD) is a Federated state, state government organization in the United States, in charge of maintaining public transportation, roadways, bridges, canals, select levees, floodplain mana ...
(DOTD) in order to highlight the unique history of Louisiana's
Florida Parishes
The Florida Parishes, on the east side of the Mississippi River—an area also known as the Northshore or Northlake region—are eight parishes in the southeastern portion of the U.S. state of Louisiana.
The Florida Parishes were part of what ...
.
Louisiana is in the process of widening I-12 to three lanes in each direction in locations such as Covington and Mandeville where the Interstate is still two lanes in each direction.
Route description
Baton Rouge to Hammond
From the west, I-12 begins east of downtown
Baton Rouge
Baton Rouge ( ; , ) is the List of capitals in the United States, capital city of the U.S. state of Louisiana. It had a population of 227,470 at the 2020 United States census, making it List of municipalities in Louisiana, Louisiana's second-m ...
in
East Baton Rouge Parish
East Baton Rouge Parish (; ) is the most populous List of parishes in Louisiana, parish in the U.S. state of Louisiana. Its population was 456,781 at the 2020 United States census, 2020 census. The county seat, parish seat is Baton Rouge, Louis ...
at an interchange with
I-10 known as the I-10/I-12 split. While I-10 heads to the southeast toward the
New Orleans metropolitan area
The New Orleans metropolitan area, designated the New Orleans–Metairie metropolitan statistical area by the Office of Management and Budget, U.S. Office of Management and Budget, or simply Greater New Orleans (, ), is a List of United States me ...
, I-12 proceeds eastward toward the North Shore of
Lake Pontchartrain
Lake Pontchartrain ( ; ) is an estuary located in southeastern Louisiana in the United States. It covers an area of with an average depth of . Some shipping channels are kept deeper through dredging. It is roughly oval in shape, about from w ...
. Before leaving Baton Rouge, I-12 intersects some of its major arteries, including
Louisiana Highway 3064 (LA 3064; Essen Lane) and
LA 73 (
Jefferson Highway) via
LA 1068 (Drusilla Lane). It then passes through a cloverleaf interchange with
US 61 (
Airline Highway). These three exits serve several of the area's key medical and shopping centers, such as the
Our Lady of the Lake Regional Medical Center and
Cortana Mall. The final exit in Baton Rouge is an interchange with
LA 3245 (O'Neal Lane), which serves the
Ochsner Medical Center-Baton Rouge and eastern suburbs.
I-12 reaches the
Amite River
The Amite River () is a tributary of Lake Maurepas in Mississippi and Louisiana in the United States. It is about long. It starts as two forks in southwestern Mississippi and flows south through Louisiana, passing Greater Baton Rouge, Louisia ...
later, where it enters
Livingston Parish and the city of
Denham Springs. I-12 skirts the southern edge of town, providing interchanges with
LA 3002 (South Range Avenue) and
LA 1026 (Juban Road). East of Denham springs, I-12 skirts the southern edge of Livingston Parish's only other city,
Walker
Walker or The Walker may refer to:
People
*Walker (given name)
*Walker (surname)
*Walker (Brazilian footballer) (born 1982), Brazilian footballer
Places
In the United States
*Walker, Arizona, in Yavapai County
*Walker, Mono County, California
* ...
. The interstate's sole exit in Walker is exit 15, an interchange with
LA 447.
Past Walker are smaller communities in the eastern half of the parish. Exits include:
LA 63 serving
Livingston (exit 22),
LA 441 serving
Holden
Holden, formerly known as General Motors-Holden, was an Australian subsidiary company of General Motors. Founded in Adelaide, it was an automobile manufacturer, importer, and exporter that sold cars under its own marque in Australia. It was ...
(exit 29), and
LA 43 serving
Albany and
Springfield (exit 32).
Shortly after crossing the
Natalbany River into
Tangipahoa Parish, I-12 intersects
LA 1249, which leads to the communities of
Baptist
Baptists are a Christian denomination, denomination within Protestant Christianity distinguished by baptizing only professing Christian believers (believer's baptism) and doing so by complete Immersion baptism, immersion. Baptist churches ge ...
and
Pumpkin Center. I-12 enters into a
cloverleaf interchange
A cloverleaf interchange is a two-level interchange (road), interchange in which all turns are handled by slip roads. To go left (in right-hand traffic; reverse directions in left-driving regions), vehicles first continue as one road passe ...
later with
I-55 at the southeast corner of
Hammond, the largest city in Tangipahoa Parish. I-55 heads toward
Jackson, Mississippi
Jackson is the List of capitals in the United States, capital and List of municipalities in Mississippi, most populous city of the U.S. state of Mississippi. The city sits on the Pearl River (Mississippi–Louisiana), Pearl River and is locate ...
, on the north and
New Orleans
New Orleans (commonly known as NOLA or The Big Easy among other nicknames) is a Consolidated city-county, consolidated city-parish located along the Mississippi River in the U.S. state of Louisiana. With a population of 383,997 at the 2020 ...
on the south. after,
US 51 crosses I-12, but the two roads do not intersect. There is instead an interchange with
US 51 Business, which serves downtown Hammond, as well as the city of
Ponchatoula to the south.
Hammond to Slidell
East of Hammond are two rural exits in southeastern Tangipahoa Parish:
LA 3158 (Airport Road) to
Hammond Northshore Regional Airport and
LA 445 to
Robert
The name Robert is an ancient Germanic given name, from Proto-Germanic "fame" and "bright" (''Hrōþiberhtaz''). Compare Old Dutch ''Robrecht'' and Old High German ''Hrodebert'' (a compound of ''Hrōþ, Hruod'' () "fame, glory, honour, prais ...
.
Just after crossing into
St. Tammany Parish, I-12 curves to the southeast and begins to parallel the North Shore of Lake Pontchartrain. An interchange with
LA 1077 serves the town of
Madisonville to the south. The following exit, an interchange with
LA 21, also connects to Madisonville as well as the parish seat of
Covington to the north. Immediately before crossing the
Tchefuncte River, an exit to Pinnacle Parkway and East Brewster Road serves the growing shopping area east of LA 21.
east of the bridge, I-12 passes through an interchange with
US 190 between Covington and
Mandeville. This section of US 190 serves as St. Tammany Parish's busiest north–south thoroughfare, connecting Covington and surrounding points with the
Lake Pontchartrain Causeway
The Lake Pontchartrain Causeway (), also known simply as The Causeway, is a fixed link composed of two parallel bridges crossing Lake Pontchartrain in southeastern Louisiana, United States. The longer of the two bridges is long. The southern ...
, a bridge leading to New Orleans. Further exits in St. Tammany Parish west of
Slidell include
LA 59 to Mandeville and
Abita Springs,
LA 1088 to
LA 36, and
LA 434 to
Lacombe.
I-12 passes through an interchange with Airport Drive east of the Lacombe exit, which connects to
Slidell Airport due north. At this exit, I-12 enters the northern edge of Slidell. An interchange with
US 11 connects to the downtown area. Less than later, I-12 reaches its eastern terminus at a major interchange with I-10 and
I-59 at the northeast corner of town. From this interchange, I-10 heads southwest toward New Orleans and east toward
Bay St. Louis, Mississippi, while I-59 heads north toward
Hattiesburg, Mississippi
Hattiesburg is a city in the U.S. state of Mississippi, located primarily in Forrest County, Mississippi, Forrest County (where it is the county seat and most populous city) and extending west into Lamar County, Mississippi, Lamar County. The ci ...
.
History
I-12 was added to the highway system on October 17, 1957, with I-12 running from I-10 in Baton Rouge to I-59 north of
Slidell.
By the mid-1960s, the routes had been realigned to their current configuration, with I-12 and I-59 both ending at I-10 near Slidell. The route was opened to traffic in several sections between January 1967 and June 1976.
With major damage to the
I-10 Twin Span Bridge
The I-10 Twin Span Bridge, officially known as the Frank Davis "Naturally N'Awlins" Memorial Bridge, is a nearly causeway near New Orleans. It consists of two parallel trestle bridges. These parallel bridges cross the eastern end of Lake Pon ...
across
Lake Pontchartrain
Lake Pontchartrain ( ; ) is an estuary located in southeastern Louisiana in the United States. It covers an area of with an average depth of . Some shipping channels are kept deeper through dredging. It is roughly oval in shape, about from w ...
from
Hurricane Katrina
Hurricane Katrina was a powerful, devastating and historic tropical cyclone that caused 1,392 fatalities and damages estimated at $125 billion in late August 2005, particularly in the city of New Orleans and its surrounding area. ...
, I-12 was temporarily functioning as I-10 between Baton Rouge and Slidell. On October 14, 2005, the eastbound span of I-10 over Lake Pontchartrain reopened to two-way traffic. The westbound span of I-10 reopened on January 6, 2006, with speed, weight and size restrictions, relieving I-12 of much of the congestion that was clogging it from the
Lake Pontchartrain Causeway
The Lake Pontchartrain Causeway (), also known simply as The Causeway, is a fixed link composed of two parallel bridges crossing Lake Pontchartrain in southeastern Louisiana, United States. The longer of the two bridges is long. The southern ...
to the junction with I-10 and I-59.
Since 2012, the DOTD has been widening the Interstate from four lanes to six lanes to accommodate the increasing amount of traffic and make the section safer.
The I-10/I-12/I-59 split, notorious for rough pavement, was repaved in 2015.
Exit list
See also
*
References
External links
La DOTD State, District, and Parish Maps
{{DEFAULTSORT:I012
12
12
Transportation in East Baton Rouge Parish, Louisiana
Transportation in Livingston Parish, Louisiana
Transportation in St. Tammany Parish, Louisiana
Transportation in Tangipahoa Parish, Louisiana