From the southeast, LA 650 began at an intersection with LA 316 (Bayou Blue Road) at a point just east of Gray. It proceeded in a northerly direction along Bayou Blue Bypass Road. LA 650 briefly jogged to the east then back to the north, separating from Bayou Blue Bypass Road. It continued north along the Terrebonne – Lafourche Parish line to Martinez Road. Here it turned west onto Waterplant Road, skirting the southern boundary of Schriever. LA 650 entered Schriever then made a jog to the north and back to the west, proceeding to its terminus at LA 24.
LA 650 was an undivided two-lane highway for its entire length.
The route initially heads west from a boat launch on Bayou Cut Off then turns north and crosses US 90 via an overpass. The freeway is accessed indirectly by the north service road. LA 652 zigzags west, then northwest along Bayou Folse, north across Bayou Cutoff, and finally northwest a short distance to an intersection with LA 182 just inside Raceland. LA 652 is an undivided two-lane highway for its entire length.
The route heads north from an intersection with Eagle Island Road, a local road, and crosses Bayou Du Mar. It then crosses US 90 via an overpass. The freeway is accessed indirectly by the north service road. LA 653 continues north to an intersection with LA 182 south of Raceland. It is an undivided two-lane highway for its entire length.
Until recently, LA 653 extended west from its current southern terminus along what is now a private road to a second intersection with LA 182, existing as a loop off of that highway. In this form, LA 653 was part of the original route of the Old Spanish Trail, designated as State Route 2 in 1921 (in the pre-1955 Louisiana Highway system) and US 90 in 1926. This route was bypassed in 1938 when US 90 was moved onto what is now LA 182. LA 182 was then bypassed by the current route of US 90 in 1977 (north of Exit 210) and in 1999 (south of Exit 210).
The route heads northeast from LA 1 and immediately crosses a vertical lift bridge over Bayou Lafourche. It then intersects LA 308 which, like LA 1, follows alongside the bayou. 4.4 miles (7.1 km) later, LA 654 curves to the south and proceeds a short distance to a bridge at the Company Canal. A private road crosses the canal and proceeds toward the Golden Ranch Plantation in Gheens. LA 654 is an undivided two-lane highway for its entire length.
The route begins at the intersection of Main and Vacherie Streets in Lockport. It immediately crosses a swing bridge across Bayou Lafourche into the unincorporated community of Rita. It then turns east and follows East Main Street to a junction with LA 308, the primary highway along the east bank of the bayou. LA 655 is an undivided two-lane highway for its entire length. A spur, 0.44 miles (0.71 km) in length and signed as the mainline route, follows Vacherie Street in Lockport from the bridge to LA 1 (Crescent Avenue).
LA 655 was formerly a loop that encompassed Main Street in Lockport, connecting with LA 1 on the east side of Lockport. The route also had a spur, signed as the mainline route, that consisted of an alternate connection to LA 1 along Vacherie Street in Lockport. This mileage was all transferred to local control in 2019 as part of La DOTD's Road Transfer Program.
The route proceeded eastward from an intersection with LA 316 (Bayou Blue Road) along the remains of Lake Long Bayou to a dead end west of the Company Canal and Lake Long. It was an undivided, two-lane highway for its entire length.
Louisiana Highway 657 (LA 657) runs 2.51 miles (4.04 km) in a north–south direction from LA 3235 in Larose to the end of state maintenance just north of Larose in Lafourche Parish.
The route heads northeast from LA 3235 and intersects LA 1, which follows the west bank of Bayou Lafourche. It proceeds immediately across a vertical lift bridge over the bayou and intersects LA 308. Here, LA 657 turns west alongside Bayou Lafourche while LA 308 continues straight ahead. Reaching the Gulf Intracoastal Waterway, LA 657 turns again to the northeast and crosses underneath LA 308. State maintenance ends just beyond Pump Station 7 Road, a local road. LA 657 is an undivided two-lane highway for its entire length.
The route proceeded north from LA 20 along North Main Project Road (Parish Road 29), immediately crossing the Southern Pacific Railroad tracks (now the BNSF/Union Pacific Railroad). LA 658 then turned east onto Broadway Avenue, running parallel with the rail line, and continued to a point on the bypassed portion of LA 20 now known as Old Schriever Highway. It was an undivided, two-lane highway for its entire length.
The route heads east from LA 24, which changes from a divided four-lane highway flanking Bayou Terrebonne to an undivided two-lane highway running along the west bank of the bayou. LA 659 proceeds along the east bank and exits the city of Houma. After curving to the southeast, it intersects LA 3087 (Prospect Boulevard). The highway continues southeast to Presquille and a second intersection with LA 24, which crosses to the east bank of the bayou. LA 659 is an undivided two-lane highway for its entire length.
The route heads northeast from LA 24, which travels on either side of Bayou Terrebonne. It then curves to the southeast, running parallel to the limits of Bayou Cane and Houma. LA 660 intersects LA 182 and LA 3087, which connect Houma to eastbound US 90. The route ends at an intersection with LA 316 on the Terrebonne–Lafourche parish line. It is an undivided two-lane highway for its entire length.
The route heads northeast from an interchange with LA 315 (Bayou Dularge Road) and immediately crosses a swing bridge over the Houma Navigation Canal. It then crosses a vertical lift bridge over Bayou La Carpe and enters the city of Houma where it travels along South Van Avenue. In Houma, LA 661 intersects LA 57 (Grand Caillou Road) and LA 3040 (Tunnel Boulevard). Crossing LA 3040, the highway curves to the north as Howard Avenue and proceeds to LA 24 (Main Street) at Bayou Terrebonne. A locally maintained vertical lift bridge crosses the bayou and connects to LA 659 (Park Avenue), which follows the opposite bank. LA 661 is an undivided two-lane highway for its entire length.
LA 662 heads north on Oilfield Road through Boeuf and crosses underneath the Bayou Boeuf bridge on US 90 Bus./LA 182. It immediately turns east, briefly running alongside US 90 Bus./LA 182 before resuming its northern course, now in a concurrency with US 90 Bus. (LA 182 continues eastward into Terrebonne Parish alone.) The concurrency ends at an interchange with Exit 182 on US 90, after which LA 662 proceeds north then curves northeast to Bayou L'Ourse, intersecting LA 663 and LA 398. The latter heads north to Labadieville, connecting LA 662 with the rest of Assumption Parish. LA 662 then curves back to the southeast, passing through a second interchange with US 90 at Exit 185 and terminating at LA 182 in an area known as Zacarter.
LA 662 is generally an undivided two-lane highway but widens to a divided four-lane highway in the vicinity of the two interchanges with US 90.
Louisiana Highway 664 (LA 664) runs 0.82 miles (1.32 km) in a north–south direction along St. Charles Street in Houma, Terrebonne Parish.
The route begins at LA 311 (Little Bayou Black Drive) and proceeds north along the Houma–Bayou Cane line. Almost midway through its route, LA 664 intersects LA 3040 (Tunnel Boulevard), a four-lane highway that runs southeast to northwest through Houma and Bayou Cane. At the end of its route, LA 664 intersects eastbound LA 24 (Main Street), crosses a bridge over Bayou Terrebonne, and terminates at westbound LA 24 (Park Avenue). LA 664 is an undivided four-lane highway with center turning lane from LA 311 to LA 3040, after which point it narrows to an undivided two-lane highway for the remainder of its route.
Louisiana Highway 665 (LA 665) runs 9.88 miles (15.90 km) in a northwest to southeast direction from LA 55 in Montegut to a dead end at the Cutoff Canal southeast of Montegut, Terrebonne Parish.
The route initially heads northeast from LA 57 in an area known as Pointe Aux Chenes at the northern limit of Montegut. After 1.1 miles (1.8 km), LA 665 turns to the southeast to run alongside Bayou Pointe Au Chien. The highway continues for another 8.8 miles (14.2 km) to the Pointe Au Chien Landing at the Cutoff Canal. LA 665 is an undivided two-lane highway for its entire length.
LA 671 begins at the intersection of LA 668 (East Admiral Doyle Drive) on the boundary between Jeanerette and unincorporated Iberia Parish just northeast of an interchange with U.S. Route 90 and Future Interstate 49. It travels northeast along the two-lane Canal Street in a relatively rural part of the city. After about three-quarters mile (1.2 km), the highway enters a residential neighborhood also passing by some city offices. It crosses a railroad at-grade and passes a manufacturing plant before reaching an intersection with Main Street, LA 182. The two highways head northwest along Main Street for about one-tenth mile (0.16 km) passing some businesses. At the intersection with Lewis Street, in front of the city hall, LA 671 heads to the northeast along this street. It crosses Bayou Teche on a small swing bridge, passes a few more houses and a church, and ends at LA 87.
Louisiana Highway 673 (LA 673) is a short 0.73-mile long (1.17 km) state highway around the unincorporated Iberia Parish community of Patoutville. It begins along Patout Road at the driveway for M.A. Patout & Son, a sugar mill. Patout Road continues due south as a parish road. The highway heads north passing a church and the small residential neighborhood comprising Patoutville. It makes a slight curve to the northwest before ending at a Y-intersection with LA 85. LA 673 is proposed to be transferred to local control under the La DOTD Road Transfer Program.
Louisiana Highway 688 (LA 688) is an east–west two-lane state highway in rural Vermilion Parish. It is 1.38 miles (2.22 km) long and connects LA 689 at its southern terminus (at LA 688's western terminus near Henry) and LA 331 at its southern terminus (LA 688's eastern terminus near Boston). The entire highway is two lanes wide and travels through farm fields. Near the midpoint of the highway, LA 688 crosses a small waterway and provides access to a boat launch. Under the La DOTD Road Transfer Program as of June 2019[update], LA 688 is set to be transferred to local jurisdiction.
Louisiana Highway 689 (LA 689) is a short 1⁄2-mile-long (0.80 km) state highway in rural Vermilion Parish near the community of Henry. It travels north–south from the western terminus of LA 688 to LA 330. The southern half of the highway is within farmland while the northern half passes a church, and elementary school, and a few houses. As of June 2019[update], the highway is proposed to be transferred to local jurisdiction under the La DOTD Road Transfer Program.
The route formerly extended west across LA 343 then south to LA 696 just west of Meaux, but this mileage was transferred to local control in 2019 as part of La DOTD's Road Transfer Program. As of 2019, the entire route of LA 697 is proposed for deletion as it does not meet a significant interurban travel function as determined by La DOTD's Road Transfer Program.
^ abcdLafourche Parish (Northwest Section)(PDF) (Map). Cartography by La DOTD Office of Multimodal Planning. Louisiana Department of Transportation and Development. February 2012. Retrieved October 5, 2013.
^ abLafourche Parish (Northeast Section)(PDF) (Map). Cartography by La DOTD Office of Multimodal Planning. Louisiana Department of Transportation and Development. February 2012. Retrieved October 5, 2013.
^ abcdLouisiana Department of Transportation and Development, Highway Inventory Unit (2019). "LRS Conversion Tool". Louisiana Department of Transportation and Development. Retrieved July 1, 2019.