State Police early Tuesday opened up sections of Interstate 10 in south-central Louisiana to local traffic, but continued to detour other traffic on the interstate due to a flooding Mermentau River.

Interstate travelers are still being routed north at Interstate 49 in Lafayette and at U.S. 165 in Iowa, then onto U.S. 190, Master Trooper Brooks David said.

David said motorists can merge onto I-10 in both directions from roads in Lafayette and other locales. But they cannot travel past Exit 82, located east of Crowley.

Water from a flooding Mermentau River continues to gum up interstate travel, as a section of I-10 just north of Crowley is under water.

In Vermilion Parish, State Police also have opened one southbound lane of U.S. 167, David said.

State Police had closed both southbound lanes of U.S. 167.

The closures have taken place after historic rainfall hit south Louisiana late last week and over the weekend, flooding thousands of homes, including hundreds in Vermilion Parish.

In Crowley, Police Chief Jimmy Broussard said more of the city found itself under water Tuesday, and that the water had drifted south into the city's historic district.

Broussard estimated 35 to 40 percent of the city had flooded, and that some 200 residents had been rescued.

The Red Cross has set up a shelter at the International Rice Festival Building at 717 West Mill St., which Broussard said had about 50 evacuees Tuesday morning.

Officials have not issued a mandatory evacuation order.

Also Tuesday, the federal government declared the parishes of Acadia, Lafayette, Iberia, St. Landry and Vermilion as disaster areas. The designation clears the way for federal relief money and other government aid to flood victims.

The Acadiana parishes join Ascension, East Feliciana, Pointe Coupee, Tangipahoa, St. Helena, East Baton Rouge and Livingston parishes.

Follow Billy Gunn on Twitter, @BillyGunnAcad.