NEW ROCHELLE, N.Y. (CBSNewYork) — Students at the biggest high school in Westchester County will have to wait to return to school.

Storm damage is delaying the start of in-person learning in New Rochelle, a major disappointment for students who wanted to start the year with a return to normal, CBS2’s Tony Aiello reported Thursday.

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The twin lakes that frame New Rochelle High School make for a pretty scene, but contributed to an ugly mess after the storm on Sept. 1.

Rain and sewage mixed with chemicals stored in the flooded basement, resulting in a toxic stew. Everything it touched must be ripped out and replaced.

Disaster crews are using a specialized instrument to detect contaminated water that soaked into the walls.

The superintendent said the mess will delay the stay of in-person classes for weeks.

“We’ve got 40 air purifying scrubbers there now just cleaning the air. We’ve gotta be really thorough because not only do you have that contaminated water, but it has seeped into every possible crevice,” said Superintendent Jonathan Raymond.

It’s a huge disappointment for high school junior Skye Hill to start the year with remote instruction.

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“She was really hopeful to go into school, first thing in person in September and get a sense of normalcy again,” said Kamili Bell-Hill. “No one foresaw what was gonna happen with this storm.”

Flooding also did major damage at the historic Thomas Paine Cottage, filling the basement and ruining the furnace.

“I’ve never seen anything like it at all. North Avenue had water on it, the high school was completely flooded in the front,” said Susanne Tanswell, chair of the museum.

“The whole street was engulfed with water and it was very scary,” said Gary Bush.

At the high school, teams are working day and night hoping to clean up and seal off the damaged areas so classes can resume.

The district is exploring a couple options for a quicker return to in-person instruction, such as holding classes off-site or in temporary structures like tents.

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The non-profit Thomas Paine Cottage and Museum is also raising funds to repair damage to the historic site. Click here to donate.

Tony Aiello