MAN THE DIKES!

By JAMES WALSH

FIFTY YEARS AFTER WORLD WAR II, SOMETHING LIKE BLITZKRIEG returned to Nijmegen last week. Dutch soldiers swarmed around the city while low-flying helicopters thundered overhead. Sirens pierced the air as police cars escorted emergency crews and equipment into town. The scenes reflected the kind of combat the Dutch know best: struggling with the elements. This time, in a country wrested largely from the sea, nature's attack arrived by way of the less fortified back door. At Nijmegen's Jan Massink sports center, a sports club where 350 evacuees had bedded down on the gymnasium floor, factory worker Jan Hooyman, 40, explained the danger sign. ``When clear water appears at our doorstep, that's O.K.,'' he said. ``But when we see brown water, we know that's the dike giving way.''

Clear, brown or in between, water in tidal-wave volumes was sloshing over the banks of the Rhine and other major rivers, drowning vast stretches of northwestern Europe. In a week when happiness was a dry attic, a crow flying over the countryside would have needed not only its own rations but pontoon landing gear. Torrential rains had combined with unseasonable melting of Alpine snows to surcharge waterways funneling into the Low Countries. Though the Dutch remained mostly dry, the largest evacuation ever mobilized in the Netherlands cleared 250,000 people from their homes in Gelderland and Limburg, two southern provinces where 550 km of dikes were straining to burst at critically weak points. A placid landscape of willows and windmills threatened abruptly to become Apocalypse Now: if the dikes go, the lives and savings of tens of thousands of people would be swept away. Almost all the embankments were holding as last week ended, but a red alert persisted. Saturation had made the dikes top heavy and even more unstable as water levels subsided. As soldiers continued to rush sandbags into otherwise deserted southern towns, authorities put together emergency plans for bolstering the shakiest bulwarks more permanently. ``Holland has a long history and a great reputation when it comes to defending ourselves against the sea,'' Prime Minister Wim Kok reminded Parliament. Now that the rivers seemed at least as great a peril, he declared, ``we must show what we're worth in this regard as well.''

The Dutch crisis was most dire, but Europeans elsewhere were also scrambling to escape the second epic deluge in 13 months. Upriver, in Germany, the Rhine rose to 10.69 m at Cologne, equaling the century's record height dating from 1926. Overflows turned the riverside Altstadt, or old town, a tourism and entertainment quarter, into a Venice North. Murky waters gurgling through the medieval byways filled the basement of the Philharmonic Center. Still, the music managed to triumph. Pumps labored through the evening to keep the concert hall dry, and the orchestra, like the band on the Titanic, played on.

Citizens piled up 330,000 sandbags to seal off doors, windows, garages and cellars. Altogether, six German states along the Rhine, Main, Mosel and Nahe were engulfed by the rampaging rivers, barely more than a year after the Christmas 1993 floods. From Bavaria to the Dutch border, the washouts brought normal riverside life almost to a standstill and kept the Bundeswehr busy deploying rescue teams in rubber dinghies. Waters lapped at the doors of Bonn's new parliament building, and smaller sections of Frankfurt were also overrun. Shipping was suspended entirely along the lower reaches of the Rhine, the world's busiest inland waterway. In Koblenz the river rose to 9.27 m and surrounded the newly restored bronze statue of Kaiser Wilhelm I. The Emperor's bronze likeness appeared to be riding a sea horse.

The most extensive overflows hit France, where flooding to one degree or another occurred across almost all of the country's northern half. The Meuse, or Maas to German and Dutch speakers, topped off at 6.15 m above its normal level and spread in some places 3 to 4 km beyond its banks in the waterlogged Ardennes. At least 3,000 houses were inundated in Charleville-Mezieres, the site of widespread damage just 13 months ago. Citizens passing a bronze plaque defining the 1993 high-water level watched the Meuse gradually reach and swallow the marker last week.

Currents were so strong in parts of the city that outboard motors strained uselessly--an oddly fitting trial for the birthplace of Arthur Rimbaud, one of whose most famous poems was Le Bateau Ivre (The Drunken Boat). In the calmer Charleville streets of Rimbaud's boyhood district, swans cruised nonchalantly like grand seigneurs inspecting their expanded watery estates. Downstream in Belgium, the Meuse overpowered a number of evacuation efforts in the town of Dinant. Householder Tony Delussu was exasperated after two floods. ``I'd just finished putting new wallpaper in my living room,'' he explained. ``I won't stay around the Meuse any more. It's over--I'm leaving.''

In addition to melting snows, what swamped the Continent's richest countries under the century's highest water levels was a persistent stream of warm air blowing off the Atlantic and producing marathon rainfalls. Last month Belgium received more than three times its normal amount of rain. From the Rhine to the Loire and the North Sea, France too has been battered by Niagara-like downpours. Normandy and Brittany got almost one-third of their average annual rainfall from Jan. 17 to 28. In Rennes, the Breton capital, showers dropped an astonishing 70 liters of rain per sq m in a 24-hour span of Jan. 22 to 23, breaking a 111-year record.

Paris, in all events, managed to keep its skirts above water. Although the Seine swelled 4.92 m higher than its normal level, the flow blocked only some riverside expressways and prompted the closure of some tunnels under the river as a precaution. But the exemption did not mean that Paris was ignoring the ordeals going on around it. The world's heaviest concentration of chattering raisonneurs were quick to join critics in the Low Countries and Germany to point the finger of blame. In their view, the great flood's archvillain was a usual suspect: overdevelopment.

Over the past few decades, builders have transformed large tracts of France's countryside into shopping malls, parking lots and highways. The paved-over terrain has ``doubled or even tripled'' the volume of unabsorbed water runoff, according to Claude Allegre, president of the Office of Geological and Mineral Research. Allegre warned, ``Let's be clear: the frequency of flooding is going to increase and occur farther and farther upriver.'' Farmers eager to make their work more efficient have also ripped out hedgerows and filled in ditches. What used to be patchworks of fields plowed at right angles to one another are now consolidated under parallel plowing that drains in one direction. Said French Environment Minister Michel Barnier: ``You have to understand that 770,000 km of hedgerows have vanished from our countryside since the 1960s, with 220,000 km of those in Brittany alone. To avoid these kinds of natural catastrophes, we're going to have to change 40 or 50 years of bad practices.'' German and Dutch critics fastened on the strangulation of the Rhine, which has been forced into a steadily tighter corset since the last century. More than 90% of wetlands through which the great river once meandered has been filled in and built up.

Straightening of the upper Rhine's bends for shipping purposes has also shortened the entire course 80 km since the 1830s. Alpine runoffs that used to flow from the Swiss border to Karlsruhe in 60 hours now take half that time. Klaudia Martini, environment minister for the downriver German state of Rhineland-Palatinate, noted that regular torrents are an inevitable outcome. ``We have been raping nature for 40 years,'' she said. ``The Rhine is showing us this was wrong.''

If those culprits were not enough, the hard-pressed Dutch had no lack of their own. Too much construction? Too few wetlands set aside for overflows? Not according to the endangered folk of Gelderland, where the now billowing Rhine forks into three branches, one of them fed by the swollen Maas. Plenty of Gelderlanders were up to their necks in frustration as well as flood- prevention measures last week as officials finally got around to reinforcing the rivers' ramparts. A householder in Druten leaned out of a window in his second-floor refuge as members of Parliament inspected the town. He shouted, ``When are you guys going to stop talking and start building some dikes?''

Plans for shoring up the waterways have languished for years under a policy-review system that requires lengthy consultations. Environmentalists may have claimed the moral high ground in Germany and France last week, but Greens in the Netherlands were beset by charges of obstructionism. To many evacuees, preserving the beauty of their landscape was less important than preserving terra firma. As one result, Kok's government decided to proceed unilaterally with strengthening and elevating 70 km of the most vulnerable dikes by next November.

Until recently a country that has fought its major struggles with the sea had devoted most of its reinforcements to that front. This, after all, is a defensive line that breached disastrously in Zeeland in 1953, resulting in some 1,800 deaths. Although nothing like that calamity afflicted Europe last week--all told, the floods killed about 30 people, including only three in the Netherlands--the Dutch seemed prepared to take no more chances with the river dikes. Built of clay packed around a sand core, the structures in many parts date back to the 13th century. The village of Ochten seemed especially jeopardized as water soaked through the sand interior, releasing telltale flows of brown water.

Emergency personnel deployed to sandbag the walls and line the dikes' river sides with plastic sheeting could only help relieve part of the crisis. In shipshape Dutch style, the evacuation proceeded in a remarkably orderly manner; the notices went out by post. Even so, a bit of unforeseen chaos ensued when some highways became paralyzed with traffic. Seemingly every car and truck that could move was pressed into carrying refugees burdened with cargo ranging from pigs to pianos. Saving livestock put unusual pressures on vehicles and roads. As the exodus progressed, the Ouwehands Zoo in Rhenen, just north of the flood zone, turned into a latter-day Noah's ark. For three days the zoo took in streams of animals, from household pets to ponies, donkeys, pheasants and kangaroos. Custodian Peter van der Eijk reported wearily, ``We're high and dry here, but we're completely full.'' Attic rooms, church lofts and the second floors of still busy taverns up and down northern Europe's waterways were feeling more than crowded as well. Ouwehands' zoo keepers had a relatively simple time. At least the animals were not busy passing the blame.

--Reported by Bruce Crumley/Paris, James Geary/Amsterdam, Rhea Schoental/Bonn and Bruce van Voorst/Nijmegen

With reporting by BRUCE CRUMLEY/PARIS, JAMES GEARY/AMSTERDAM, RHEA CHOENTAL/BONN AND BRUCE VAN VOORST/NIJMEGEN