( Reuters ) - The Netherlands and Britain, facing their worst flood threat in decades, closed surge barriers and evacuated people from homes on Friday as a North Sea storm threatened to inundate low-lying areas.
Authorities compared the approaching conditions to those in 1953 when floods killed more than 2,000 people in both countries.
The massive surge barrier near the Dutch port city of Rotterdam was closed for the first time since its construction in the 1990s.
At 11 p.m. (5 p.m. EDT) on Thursday, the two arc-shaped steel doors of the Maeslant barrier edged into the waterway that connects Rotterdam to the North Sea.
As spectators braved rain and wind to watch from a narrow headland, it took about half an hour for the two doors to meet in the Nieuwe Waterweg, about 360 meters wide.
"We have been standing here since 8 p.m.," said student Denise from Rotterdam. "I had expected it to close a bit faster."
A Dutch transport ministry spokesman said: "At 2.15 a.m., we are expecting the water to reach the highest level at 2.84 meters above mean sea level."
Earlier forecasts for the water level had been for more than 3 meters. The flood of 1953 saw the water rise to 3.85 meters above sea level, the transport ministry said.
The flood defenses of the entire Dutch coast were put on alert and the Oosterschelde barrier in the south of the country was also closed, the ministry spokesman said.
In Britain, large areas of the Norfolk and Kent coasts are at risk of severe flooding, the government and environment agencies said.
"A tidal surge of up to three meters is making its way down the North Sea which could coincide with high tides," Environment Secretary Hilary Benn told parliament.
A special meeting was held by Prime Minister Gordon Brown to coordinate the emergency response, a spokeswoman said.
"There is a risk of flood defenses being overtopped on the coast and in tidal rivers especially in East Anglia, particularly the Norfolk Broads, the coast south of Great Yarmouth, including Lowestoft, and areas south of this as far as the coast of Kent," Benn said.
Britain's Met Office said north-westerly winds exceeding 80 kph were coinciding with low pressure and high tides to produce the exceptional conditions. The Thames Barrier which protects London from flooding was closed late on Thursday, the agency said.
British authorities evacuated hundreds of elderly residents from at risk areas and delivered sand bags to homes along parts of the east coast.
The floods in 1953 killed around 300 in England and more than 1,800 in the Netherlands. Two thirds of the Netherlands would have been permanently flooded but for an elaborate system of dikes and canals.
"The storm conditions are very similar to 1953," the Dutch ministry spokesman said. The government weather service forecast force nine winds for parts of the Dutch coast.
Shipping to and from Rotterdam harbor is expected to remain suspended until 12 a.m. EDT on Friday, a port spokesman said.
Rotterdam, a major transit point for oil, coal, grains and other commodities, handles about 35 percent of European port traffic by tonnage. About 60 ships will be affected by the closure of the port.