BellSouth says damage to its network from Hurricane Katrina could reach $600 million.

The carrier, which serves a nine-state region in the Southeast -- including the hurricane-torn states of Louisiana, Mississippi and Alabama -- says it lost 810,000 lines, roughly one-sixth of the 4.7 million lines BellSouth has in service in the area. Earlier this week, BellSouth said 1.75 million lines were affected by the storm. (More Katrina news)

BellSouth also said 19 of the 131 central offices in the Gulf Coast area were disabled. Those 19 central offices serve 187,000 access lines, 166,000 of which are in the devastated city of New Orleans. Restoration plans for the 19 central offices are in development, BellSouth says.

Service to most customers will be restored within 30 days, the carrier says, though some communities may take longer to rebuild, depending on when residents and businesses are able to return to those areas and the time it takes to rebuild local infrastructure.

New Orleans, with floodwaters that may take months to recede, is "an atypical situation," the carriers says, and because of this BellSouth will track restoration activity separately. BellSouth is prioritizing service restoration on those customers involved with public safety concerns and relief efforts. Wireless service restoration is also a priority, the carrier says.

"Our overall restoration activities are ongoing and we are making good progress daily," BellSouth CTO Bill Smith said in a statement.

The carrier says it is too early to project the total magnitude of destruction caused by Hurricane Katrina. But based on the information currently available and without the opportunity to survey and physically assess the entire area, BellSouth's initial estimate is a cost of $400 million to $600 million, including both capital and expense, for network restoration.

BellSouth has about 13,000 employees in Louisiana, Mississippi and Alabama, 6,500 of which are in areas hardest hit by Katrina. BellSouth has set up "tent cities" in Baton Rouge and Covington, La.; and Gulfport, Hattiesburg and Jackson, Miss., to provide food, shelter, clothing, financial support and employee assistance programs for those employees.

An additional location will be established this week in Kenner, La. The cities will also serve as deployment areas for BellSouth technicians and engineers who will be sent back into affected areas to restore service for customers.