Fredericton's flood levels are expected to match -- or even surpass -- the worst flood to hit the New Brunswick capital in recorded history, as the St. John River seeps into the city.

Emergency officials are warning those who live along the river between Fredericton and Jemseg -- particularly in Maugerville and Jemseg -- to get out now.

The river begins to flood at the 6.5-metre mark, but it had reached at least 7.2 metres by late Wednesday. Residents can find updates on the situation here.

"In 1973, we had our 180-year flood which put the city of Fredericton at the 8.6-metre mark," Bob Martin, the Fredericton fire department's assistant deputy chief of operations, told CTV Newsnet.

"We're predicting that sort of landmark will be hit again sometime overnight."

The 1973 flood caused Fredericton and the surrounding farmland about $78 million in damage, according to the city's website.

Martin said Fredericton's schools and city hall will be shut down Thursday, along with parts of downtown. About 40 streets were expected to be under water by later in the week.

Cindy Abbott, a spokesperson for emergency groups working to deal with the flood, said transport vehicles have been sent to help evacuate residents from their homes -- if they choose to leave.

"People have to understand -- we're about to exceed the worst flood on record," she said.

The river could rise to 8.4 metres by Thursday morning.

"It's either going to be as big as '73 or the next best thing to it," said Andy Morton, deputy director of the province's Emergency Measures Organization during a Wednesday news conference.

Martin said officials are on standby if the flooding continues to worsen.

"We're monitoring the situation," Martin said. "We have our public safety marine units in the water and we're ready at this time."

However, he noted that a number of residents have decided to ride out the flood and have no plans to evacuate their homes.

Much of the extra river volume was due to heavy rainfall up river in the northern parts of the province, as well as record snowfall levels over the winter winter.

But officials have not yet declared the situation a crisis.

"The flooding at this point...is certainly severe enough to impede traffic on a number of roadways and certainly to fill basements and that sort of thing," Morton said earlier in the day.

"But we haven't seen any first floor damage at this point and that really concerns us when we start to see damage on the first floor of any property."

Sense of bravado

People who live along the river's banks have been warned they have a choice to either to get out or hunker down with the expectation of having to wait out the flood, since officials would have difficulty reaching them.

CTV's Lisa LaFlamme, reporting from Fredericton on Wednesday, said there were about 250 people whose homes were completely surrounded by floodwaters.

"We've been told only about 80 of them have registered, but that doesn't mean they've left," she told Canada AM, noting there seemed to be a sense of bravado among many residents who were planning to stick it out.

"People are saying you live on the river, you've got to be ready to survive a flood," LaFlamme said, standing on the edge of a massive floodplain where the river had overwhelmed its banks.

Those that stay in their homes will have to prepare for about a week without access to supplies, Morton said. He recommended stocking up on essentials such as fresh water, food, medication, and ensuring a secondary source of heat is available in case power is lost.

Mayor preparing for worst

Fredericton Mayor Brad Woodside told Canada AM he was "hoping for the best but preparing for the worst," noting that the river was expected to continue to ruse.

He said the Red Cross is ready to help, beds have been provided at universities for anyone displaced by the flood and a 24-hour emergency centre had been set up.

He agreed many of the residents are taking the flood risk in stride.

"There are people in the ... area that live with this anxiety every year and they learn to cope with it. It's a place that is unlike any other and it's the price you pay for living along the river anywhere in the world," Woodside said.