"There's no perfect solution to this problem, but if we wait, all we're doing is delaying New Jersey's recovery," Christie said at a news conference in Seaside Heights. "Waiting 18 to 24 months is not acceptable. Missing three summers at the Jersey Shore - sorry, not going to happen."
The decision speeds up what is seen as an inevitable and game-changing makeover of the Shore - replacing the traditional cottage on the sand with houses propped up one story high to allow the surge underneath in the next big storm.
That process began with changes to coastal construction rules in the 1980s, but will accelerate as those who don't comply will in two years' time have to start paying insurance premiums that Christie said could be nearly 10 times what they now pay.
The stricter standards will bring the Shore in line with forecasts that predict sea levels will rise more than a foot by 2050 and storms will grow in intensity for decades.
But it will also mean that many middle income families who cannot afford the cost of rebuilding their homes to the tighter construction standards will likely leave the Shore.
Seaside Heights Mayor Bill Akers said he had been talking with other mayors, and the consensus was that as many as 15 percent of residents might leave. But he conceded that the governor had little choice but to adopt the maps, which in Seaside Heights would mean houses on average would have to be raised three feet above their current height.
"The residents might not want to hear it right now, but I think this is going to help them," he said.
The slow pace of federal flood insurance settlements and uncertainty around the maps has fed anxiety along the Shore.
When FEMA released the maps, it told homeowners that while they were advisory, it was in their best interests to rebuild to those higher standards. But with many Shore officials planning to challenge portions of the map, the question of how to rebuild became a gamble.
Christie's decision to adopt the maps brings some certainty.
For those whose houses suffered damage greater than half their value, elevating will be a state requirement. For those who suffered less damage or none, it is technically optional, though for many the change in flood insurance rates, a requirement for getting a mortgage, will force compliance.
Still, as lawyers and engineers pore through the floodplain maps, some are likely to figure their homes' flood-danger classification will change before the maps become final, and they might wait to see how it all plays out.
The scale of the flooding projected by the new maps has drawn criticism from some local officials, who say the maps predict floods and wave destruction in neighborhoods that are too far from the ocean to ever suffer such damage.
"They're totally incorrect in certain areas," Long Beach Township Mayor Joseph Mancini said Wednesday. "Anything built on Long Beach Island after the mid-1980s didn't take in water. The existing elevations worked."
Brick Township Mayor Steve Acropolis predicted it would take 10 to 20 years to finish elevating houses along the Shore.
"I myself am going to have to wait a couple years. There's just a glut right now, and there's not enough people to do the work," he said.
The federal disaster relief bill, awaiting a Senate vote next week and expected to be signed by President Obama, will provide grants to help homeowners meet the new flood standards. But Christie conceded that in some cases the aid will not be enough to make the process affordable.
"People are going to have to make some tough decisions," he said.
Estimates of the cost of elevating houses run to $30,000 and above. The amounts often must be fronted by homeowners while they await federal aid.
There was some good news for Shore residents waiting to rebuild. Christie said that for those rebuilding on the same "footprint," the state's traditionally lengthy environmental review process for construction in coastal areas would be streamlined.
Still, he tamped down expectations about the rebuilding process, saying the goal for this summer was strictly to make the Shore "livable."
What will become of the Shore in years to come remains an open debate among policy makers, many of whom worry that with the increased flood protection standards, it will become a bastion exclusively of the wealthy.
Among the crowd gathered in the Seaside fire house to hear Christie speak was Raymond Cecere, a builder who owns two houses in Ortley Beach.
He said he would rebuild to the new flood standards, but did not think that was the case with some of his neighbors.
"I'm going to raise and do what I have to do," he said. "But there's a lot of people with no flood insurance who don't have a lot of money, and they're stuck."
Contact James Osborne at 856-779-3876 or firstname.lastname@example.org, or follow on Twitter @osborneja.