NEW YORK (AP) -- The Statue of Liberty survived Superstorm Sandy with every crown spike in place, but its surrounding island was so badly damaged that the National Park Service doesn't know when the beloved tourist attraction will reopen or how much repairs will cost.

A tour of Liberty Island on Friday showed broken railings, torn-up paving stones, damaged equipment and flood-wrecked buildings.

The storm destroyed boilers, sewage pumps and electrical systems, said David Luchsinger, the superintendent of the Statue of Liberty and of the neighboring Ellis Island.

"Our entire infrastructure on both islands, both Liberty Island and Ellis Island, was under water," he said.

Luchsinger estimated that 75 percent of Liberty Island's 12 acres was flooded, with water as high as 8 feet. The water would have been chest-high on the plaza that visitors cross en route from the ferry to the statue itself, he said.

Days after the storm, there was a controlled detonation of explosives on Ellis Island. Park Service spokesman Mike Litterst said the explosives were stored there to train bomb-sniffing dogs. They were compromised by the storm and had to be destroyed.

The Oct. 29 storm came one day after the Statue of Liberty's 126th birthday and the grand reopening of the crown - though the park was closed at the time in advance of the storm. The crown had been closed for a year for a $30 million upgrade to the monument's fire alarms, sprinkler systems and exit routes.

The rest of the statue was open during that year and had 3.7 million visitors last year, making it the 19th most visited national park in the nation.

Luchsinger said Sandy did not damage any of the work completed during the renovation.

"I can tell you that if you walked in there today it would look like we just reopened it," he said. "Not one dime of it was lost."

Historical artifacts on Ellis Island also survived intact, Luchsinger said.

Luchsinger evacuated ahead of the storm and returned Oct. 30, when Liberty Island was covered with mud and debris. Hundreds of National Park Service workers from as far away as California and Alaska have spent the past month cleaning the island and assessing the damage.

Friday's tour showed there is much still to be done. The main passenger dock was splintered but usable on Friday, while an auxiliary dock in back of the island was in pieces. Generators are supplying most power on the island, though one working transformer lights the statue itself.

A water line several feet high marked the walls, and dried seaweed was still stuck in the chain-link fence.

Luchsinger, 62, has lived on Liberty Island with his wife during his 3 1/2 years as superintendent. But no more. The storm blew the doors and windows out of the low-slung brick house, and the couple lost almost everything they owned.

"I had a digital grand piano in there," Luchsinger said. "I had a whole bunch of stuff. I had a couple of my mother's antique Tiffany lamps. ... The water was about 4 1/2 to 5 feet."

The house and adjoining staff buildings on landfill behind the statue will probably be razed and not rebuilt, Luchsinger said.

"One of the things we want to do is rebuild smartly and sustainably," he said. "The buildings on the back side of the island are not sustainable. ... To rebuild and have them flooded out again doesn't make a whole lot of sense. We probably won't have anybody living on the island any more. I'm probably the last one."