Internal memos by chief surgeon at New York-Presbyterian Hospital revealed new details about the coming threat

Internal memos by the chief surgeon at New York-Presbyterian Hospital were intended to rally the giant medical center’s doctors and nurses as they prepared to confront a surge in patients with novel coronavirus, but they also revealed new estimates about the coming threat that had not previously been public.

Medical experts in New York do not expect the number of cases to peak for another 22 to 32 days, the memo written by Dr. Craig Smith says, and the supplies of masks, equipment and available beds is well short of the impending need. He estimated the crush of patients will require from 700 to 934 intensive-care beds.

"The lower estimate exceeds our ICU capacity, even with surge construction," said Smith, a cardiac surgery pioneer who has headed the hospital’s surgery department since 2010.

Like many hospitals around the country, Smith notes they are also struggling with the limited number of personal protective equipment , or "PPE." The hospital "normally uses 4,000 non-N-95 masks a day. Currently [they are] consuming 40,000 such masks per day, which is estimated to reach 70,000 per day," Smith writes.

The dire account, which he wrote on March 20, was posted to the Twitter account at Columbia Surgery, which is part of the Presbyterian Hospital network. It was one in a growing number of posts detailing the efforts being made by doctors at one of the Big Apple's largest hospital networks.

The startling figures from Smith comes just hours after New York Gov. Andrew Cuomo announced more restrictions on state residents and businesses in order to slow the spread of the virus.

"These provisions will be enforced," Cuomo said at a Friday press conference. "There will be a civil fine and mandatory closure for any business that is not in compliance. Your actions can affect my health."

What to know about coronavirus:

• How it started and how to protect yourself: Coronavirus explained
• What to do if you have symptoms: Coronavirus symptoms
• Tracking the spread in the U.S. and worldwide: Coronavirus map

Former Homeland Security Advisor Tom Bossert told ABC News' "This Week" on Sunday morning that the coming days will require more Americans to take these threats seriously. Bossert, now an ABC News contributor, said he is concerned for the three states that have the largest number of positive cases right now including New York. "I say this, and hope i'm wrong, that this is going to overwhelm the New York health system in the coming days."

The letters from Smith appear to be intended to rally doctors to confront the immense challenge they are about to face.

"Nothing would give me greater pleasure than to apologize profusely in a few weeks for having overestimated the threat. The next month or two is a horror to imagine if we’re underestimating the threat," he writes. "Remember that our family, friends, and neighbors are scared, idle, out of work, and feel impotent. Anyone working in healthcare still enjoys the rapture of action."

In another memo, circulated Saturday, Smith referenced the famed UCLA basketball coach, John Wooden, when trying to motivate his team.

"To think we could mimic Italy seemed risible a week ago. Not today," Smith writes. "No one is standing still, wringing their hands." The chairman ends his weekend memo with an optimistic message quoting Wooden: "'Failing to plan is planning to fail'. That will not be us."

Smith told ABC News the memos are "circulating much more widely than we imagined, and are creating angst in other quarters over control of the message. I’m thinking today about how to deal with that."

In one of the letters, Smith, who supervises more than 100 full time faculty members, references the story of the sled dog named Balto who helped save infected children by carrying life-saving serum to Nome to fight the 1925 diphtheria epidemic – an inspiring story that became an animated feature film, "Balto."

A bronze statue of the hero dog has been located in New York City’s Central Park since December 1925.

"So what can we do? Load the sled, check the traces, feed Balto, and mush on," he wrote. "Our cargo must reach Nome."