U.S. 61 South at the Big Black River was reopened this morning by the Mississippi Department of Transportation, following the state’s first estimates on the flood’s impact on major industries.

Inspections on the highway leading into Claiborne County and at U.S. 61 North at Redwood before it reopened Wednesday showed both roads were ready for traffic, state engineers have said. Both sections were closed May 13. Water inside the pavement at both locations prolonged detours.

Ten miles of Mississippi 465 between U.S. 61 North and Eagle Lake and 2 miles of Mississippi 16 at Mississippi 149 remain off limits to traffic, probably until the middle of the month, officials have said.

Levels on the Lower Mississippi River system continued dropping overnight. At Vicksburg, the river was 51.15 feet, down half a foot. Similar drops were recorded this morning in Greenville, at 54.52 feet, and Natchez, at 57.76 feet.

The river crested May 19 in Vicksburg at 57.1 feet, 14.1 feet above flood stage. Levels in Memphis have dropped to 30.3 feet, where it’s expected to hover through Monday.

The governor’s office Thursday estimated 450,000 acres of cropland statewide could have been destroyed by this year’s historic flood, causing $250 million in damage. Thousands of acres remain flooded and will delay firmer numbers until more water recedes, said Laura Hipp, a spokeswoman for Gov. Haley Barbour.

A worst-case estimate by state agriculture officials said 600,000 acres of row crops and a total of 1.4 million acres of land in Mississippi could flood.

The river side of the Steele Bayou Control Structure was 99.85 feet this morning, down six-tenths of a foot. The land side was 89.93 feet, down one-hundredth of a foot.

Damage estimates to homes and other structures also aren’t available yet, Hipp said.

In Warren County, 1,340 dwellings have been evacuated, with 707 of them being primary dwellings, Warren County Emergency Management Director Gwen Coleman said. More than 3,200 people have been displaced. Figures on people and properties have been tallied by officials with Mississippi Emergency Management Agency and the City of Vicksburg and reported to the Emergency Operations Center, Coleman said.

The Associated Press contributed to this report.