Interstate 12

Interstate 12
Republic of West Florida Parkway
Route information
Maintained by LaDOTD
Length: 85.59 mi[1] (137.74 km)
Existed: October 17, 1957 – present
Major junctions
West end: I-10 in Baton Rouge
  US 61 in Baton Rouge
I-55 near Hammond
LA 445 south of Robert
LA 1077 near Goodbee
LA 21 near Madisonville
US 190 between Covington and Mandeville
East end: I-10 / I-59 near Slidell
Highway system

Main route of the Interstate Highway System
Main • Auxiliary • Business

Highways in Louisiana

← LA 11 LA 12

Interstate 12 (I-12) is an intrastate Interstate Highway located entirely within the state of Louisiana. I-12 starts in Baton Rouge at Interstate 10, and travels along the North Shore of Lake Pontchartrain before ending at the intersection of Interstate 10 and Interstate 59 near Slidell.[2] I-12 is only 85 miles long between Baton Rouge and Slidell, while I-10 takes 108 miles to travel between the same two points, so I-12 is heavily-used as a shortcut for through traffic on I-10. I-12 is six lanes from its western terminus until Exit 7 (O'Neal Lane) at which point it becomes a four-lane highway to its eastern terminus.

In 1993, the state legislature renamed Interstate 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 were erected by the Louisiana Department of Transportation and Development in order to highlight the unique history of Louisiana's Florida Parishes.

The highway is relatively short for a mainline route at only 85 miles (137 km). While Interstates 19, 66, 97, and the partially completed Interstate 99 are all shorter, none of these has two termini with the same route, much less within the same state (I-99 will eventually extend into New York). Compare the length of I-12 to that of the 73.5-mile (118.3 km) I-295 in New Jersey and Delaware, or the 72.8-mile (117.2 km) I-405 in California, or even the 121-mile (195 km) I-495 in Massachusetts, all of which are auxiliary Interstate Highways.

Contents

Route description

I-12 begins just east of downtown Baton Rouge at an interchange with I-10, with I-10 heading toward New Orleans and I-12 acting as a de-facto bypass of the New Orleans area. I-12 continues east passing through the suburbs of Baton Rouge, before transitioning into a rural interstate for the rest of its length. It makes an interchange with I-55 near Hammond. East of Hammond, the route passes near the northern shore of Lake Pontchartrain, and crosses scenic streams like the Tangipahoa River south of Robert, Sims Creek southeast of Goodbee, and the Tchefuncte River north of Madisonville. I-12 ends at I-10 and the southern terminus of I-59 near Slidell.

I-12 is the only Interstate roadway that Livingston Parish uses, as it virtually slices the parish in half.

History

Interstate 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.[3] 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.[4]

With major damage to the I-10 Twin Span Bridge across Lake Pontchartrain from Hurricane Katrina, I-12 was temporarily functioning as I-10. On October 14, 2005, the eastbound span of I-10 over Lake Pontchartrain was 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 to the junction with I-10 and I-59.

Widening and Improvements

In 2009, a project broke ground to widen I-12 from the O'Neal Lane Interchange (exit 7) to the LA 447 interchange in Walker, Louisiana. The current bottleneck has traffic backed up for a few miles.

Also, in 2010, construction began at the Louisiana Highway 1088 overpass in St. Tammany Parish to make it an exit. The finished project has a widened LA 1088 over I-12. This exit was created to alleviate conjestion on local roads and to create a more direct route to the newly opened Lakeshore High School.

In 2011, officials began constructing a third travel lane in each direction on I-12 from the Vincent's Bayou Bridge to the I-10/I-12/I-59 split.

Exit list

Parish Location # Destinations Notes
East Baton Rouge Baton Rouge I-10 west – Baton Rouge
1A I-10 east – New Orleans
1B LA 3064 (Essen Lane) to LA 73 (Jefferson Highway) No westbound exit
LA 1068 (Drusilla Lane) to LA 73 (Jefferson Highway) Westbound exit and eastbound entrance only
2 US 61 (Airline Highway) Alternate route to Baton Rouge Metropolitan Airport
Signed as exit 2A (south) and 2B (north)
4 Sherwood Forest Boulevard
6 Millerville Road
7 LA 3245 (O'Neal Lane)
Livingston Denham Springs 10 LA 3002 – Denham Springs
12 LA 1026 (Juban Road)
Walker 15 LA 447 – Port Vincent, Walker
19 Colyell, Satsuma
Livingston 22 LA 63 – Frost, Livingston
29 LA 441 – Holden
32 LA 43 – Springfield, Albany
Tangipahoa 35 LA 1249, Pumpkin Center Road, Baptist
38 I-55 – New Orleans, Jackson Signed as exits 38A (south) and 38B (north)
Hammond 40
US 51 Bus. – Ponchatoula, Hammond
To Southeastern Louisiana University
43 LA 3158 (Airport Road)
47 LA 445 – Robert
St. Tammany 57 LA 1077 – Goodbee
59 LA 21 – Madisonville, Covington
60 Pinnacle Parkway, East Brewster Road
63 US 190 – Mandeville, Covington Signed as exits 63A (Southbound to Mandeville & Lake Pontchartrain Causeway) and 63B (Northbound to Covington)
65 LA 59 – Mandeville, Abita Springs
66 LA 1088 – Mandeville
74 LA 434 – Lacombe, St. Tammany
Slidell 80 Northshore Boulevard, Airport Road
83 US 11 – Slidell, Pearl River
85A I-10 west – New Orleans
85B I-59 north - Hattiesburg
85C I-10 east - Bay St. Louis

References

Main Interstate Highways (major interstates highlighted)
4 5 8 10 12 15 16 17 19 20 22 24 25 26 27 29 30
35 37 39 40 43 44 45 49 55 57 59 64 65 66 68 69
70 71 72 73 74 75 76 (W) 76 (E) 77 78 79 80 81 82
83 84 (W) 84 (E) 85 86 (W) 86 (E) 87 88 (W) 88 (E) 89 90
91 93 94 95 96 97 99 H-1 H-2 H-3
Unsigned  A-1 A-2 A-3 A-4 PRI-1 PRI-2 PRI-3
Lists  Primary 
Auxiliary 
Other