(Bloomberg) — New Orleans warned residents to stay indoors as fires burned out of control and more than a million people were without power a day after Ida rolled ashore as a powerful hurricane. The storm, which packed some of the most powerful winds ever to hit the area, drove a wall of water inland when it made landfall Sunday, August 29, as a Category 4 hurricane about 60 miles (97 kilometers) south of New Orleans. As it lumbers north, Ida is unleashing a catastrophic amount of rain that could total 2 feet when all is said and done. Ida struck Louisiana on the 16th anniversary of Hurricane Katrina, which was the costliest cyclone in U.S. history and left much of New Orleans in ruins. Now the area's levees, pumps and other infrastructure rebuilt after that 2005 storm are being put to their biggest test yet, and the threat isn't over yet as rainfall north of New Orleans flows back down the Mississippi River. The full impact will begin to come into focus as residents get their first glimpse of the destruction. Reports of major structural damage are emerging, according to the Federal Emergency Management Agency, and analysts estimate that the storm could cost insurers at least $15 billion. Ida was downgraded to a tropical storm early Monday, August 30, as it moved inland.

Louisiana gets a first look at the destruction

Louisiana residents and authorities got their first look at the damage Monday morning, including collapsed buildings, flooded cars and runaway barges. "We are getting reports of significant structural damage across the area, potentially some buildings that have collapsed," FEMA administrator Deanne Criswell told CBS This Morning. "We are going to have a long road over the next few days." The photos emerging from the area show an abandoned SUV sunk in the floodwaters, brick buildings that were completely leveled and power lines and poles that were knocked to the ground and into buildings. The storm also knocked a major power line into the Mississippi River, according to a video posted to Twitter by the local ABC news station in Birmingham, Alabama.

Power outages expand in Louisiana, Mississippi

Across southeast Louisiana, power outages continued to expand after sunrise Monday even as Ida surged north into neighboring Mississippi and skies began to clear. More than 1.2 million homes and businesses in Louisiana and Mississippi are without power, of which about 74% are Entergy Corp. customers, according to Poweroutage.us. All eight transmission lines that deliver power into New Orleans were offline on Sunday, and backup generators were provided to New Orleans Sewage and Water Board, Entergy said on its website. The utility owner's Waterford nuclear plant, about 25 miles (40 kilometers) west of the city, was in shutdown mode using backup diesel generators after losing offsite power.

Search and rescue operations begin

Search and rescue operations have begun in Louisiana, according to a tweet from Gov. John Bel Edwards. "As of this moment, the state has deployed more than 1,600 personnel to conduct search and rescue across Louisiana," he said in the tweet. Any search and rescue operations will be complicated by the hurricane's damage. The 911 emergency response system is down, streets are blocked by debris and fallen trees, and much of southeast Louisiana is without electricity. A number of agencies are preparing to search for those who need help, including more than 4,900 members of the Louisiana National Guard.

Hurricane Ida could cost insurers at least $15 billion

Ida could cost insurers at least $15 billion, according to one of the earliest estimates, as analysts start assessing the damage from one of the most powerful storms to strike Louisiana and the Gulf Coast. That was the low end of a preliminary estimate by Wells Fargo & Co. insurance analysts led by Elyse Greenspan, who said damages covered by insurers could be as high as $20 billion, according to a note to clients on Sunday. Some past storms, including Hurricane Katrina, left extensive damage that wasn't clear until days after landfall, so early estimates are subject to major modifications. — With assistance from Brian K. Sullivan, Sheela Tobben, Josh Saul, Nancy Moran, Ari Natter, Naureen S. Malik and Katherine Chiglinsky. Related: 

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