What heavy rain did in a few hours will take weeks -- maybe even months -- to fix, says Mayor Dean Mazzarella. And it certainly won’t be cheap. At a press briefing at the city’s Emergency Management Headquarters, the mayor estimated infrastructure repairs alone will be coming in around $25 - 40 million. And then there are projects such as fortifying two vulnerable dams.

“You’re talking tens of millions of dollars,” Mazzarella said. “There’s just no way any community can afford this on their own.”

To that end, the city plans to use the grant process for some of the funds -- but that could add extra time to getting things fixed.

“Our goal is to get everybody cleaned up and get things back to normal as fast as we can,” Mazzarella said.

But ‘fast’ is a relative term. And the mayor urged residents to exercise patience as the city rises from Monday’s flooding -- which caught just about everyone by surprise. Mazzarella said while they knew rain was coming -- even heavy downpours -- no one was prepared for the magnitude of the deluge, which ranged from 9 to 11 inches over about five hours.

And that was in the absence of a tropical system.

One semblance of normalcy will return Thursday: Leominster Public Schools will reopen -- albeit with a two-hour delay. Mazzarella said the safest place for kids is in school -- something they’ve missed the last three days.

Superintendent Paula Deacon said two schools suffered flood damage -- but both will reopen.

Damage to Leominster High has been addressed, she said. But Northwest Elementary saw considerable damage to seven classrooms. That’s going to mean some shuffling around of faculty and space.

“Staff is working with the principal right now to figure out where we can place them,” Deacon said. “Some will be in gymnasiums, some will team teach... but all children will be in person.”

Deacon called Thursday’s reopening an experiment -- in that some streets might be impassable to buses -- and some bus stops may not even exist anymore. She’s asked the mayor for a full contingent of traffic officers in the morning.

And Leominster is preparing for potentially more heavy rain.

“The ground is saturated,” Mazzarella said.

In fact, on and off heavy rain fell on the city Wednesday, but didn’t seem to cause much trouble. However, eyes are on the weekend, when Hurricane Lee could make a close pass to New England.

As a precaution, the city is making thousands of sandbags available to residents. Boy Scouts, students and others volunteered to put them together and load them into vehicles behind the Emergency Management building.

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