By Anthony Deutsch
AMSTERDAM, Jan 28 (Reuters) - In a country where a third of the land is below sea level, a head of state familiar with the complexities of keeping nearly 17 million people dry can be a good thing.
So it's not entirely a coincidence that Willem-Alexander, who will take up the throne on April 30, as head of the House of Orange-Nassau and the Kingdom of the Netherlands, has been immersed in the business of water management and conservation for much of his life.
Willem-Alexander, 45, will assume his new duties after the abdication of his mother, Queen Beatrix, who turns 75 on Thursday, after living the life of a somewhat flashy heir-apparent.
The last time the Netherlands had a king, more than a century ago, was when Willem-Alexander's great-great grandfather William III held the throne. William III died in 1890, the same year that Dutch painter Vincent van Gogh shot and killed himself. Since then, queens have ruled the Netherlands.
Willem-Alexander Claus George Ferdinand, known as "Alex" to his friends and dubbed "Prince Pils" by the tabloids because of his taste for beer, has carefully built up a reputation as an expert in water management and sits on several international committees.
His marriage to a commoner, whose father was a civilian minister in Argentina's military dictatorship from 1976-1983, at first raised eyebrows.
But Maxima Zorrigueta, an attractive blonde with a down-to-earth smile, won over the hearts of the Dutch, quickly learning their language. Last year she took a dip in one of Amsterdam's canals to show people how clean they have become.
Water is no trivial matter in the Netherlands, where dikes and sea barriers hold back the North Sea and a complex system of pumps and canals keeps the land dry enough for people to live in and for its farmers to produce tulips and cheese worth billions of euros.
WE KNOW ABOUT WATER
"We like to think we know a bit about water management," Willem-Alexander said in a speech in 2009.
Willem-Alexander and Maxima have three daughters, and Beatrix had vowed to remain on the throne long enough to let her son be a father to them and not be distracted by a king's duties.
Beatrix, married at 28, raised a family of three boys in relative privacy before succeeding her mother Juliana in 1980 at the age of 43.
Once the darling of Dutch tabloids because of his love of fast cars and good-looking women, the portly prince was famous for his partying days as a college fraternity boy.
After spending six years to get a four-year degree in history, Willem-Alexander threw his efforts into frequent skiing and boating trips, and once drove a car into a ditch.
After slimming down and taking up sports -- running the New York marathon in 1992 -- Willem-Alexander has served as a member of the International Olympic Committee.
His relationship with the press, however, has been a difficult one since his wilder days.
As a boy, he once shouted "All press, piss off" at a royal photo session, and was known to use his catapult against photographers who followed the family to the Austrian ski resort Lech, where they spend winter holidays.
Willem-Alexander's younger brother, Prince Friso, had a skiing accident there last year while going off-piste and is still in a coma. (Reporting by Anthony Deutsch; Editing by Giles Elgood)