Water-Diversion Projects Strain Ties Between Portugal and Spain : Europe: Nations quarrel over their fair share of scarce resource on Iberian Peninsula. Activists cite possible damage to ecosystems.

The Portuguese have a saying about their neighbor on the Iberian Peninsula: “From Spain, neither good winds nor weddings.”

Now they add, “Nor water!”

The two nations are at odds over Spain’s campaign to help its drought-plagued south by diverting water from three major rivers that flow out of Spain and across Portugal to the Atlantic Ocean.

Portugal says the plan violates a 1968 convention on joint use of water resources. The dispute is the first major strain in relations since both countries joined the European Union in 1986.

Environmentalists on both sides of the border are angry. They say that big dams hurt ecosystems and that overuse of water to develop poor Iberian regions already has led to a damaging dependency on irrigation and tourism while the peninsula’s water table is drying up.

The activists also contend that Portugal’s government really opposes the Spanish dams because it wants to pursue its own ill-advised irrigation projects.

Spanish officials say the worries are overblown. “There is enough water on the Iberian Peninsula for the two countries’ needs,” says Adrian Baltanas, director of water projects for Spain’s Ministry of Public Works.

Portugal’s government agrees there is enough water, but says Spain is trying to take more than its fair share.

Spain wants to increase its irrigated farmland by 1.5 million acres and is planning 150 new dams and the diversion of large amounts of water from the Douro, Tagus and Guadiana rivers to its Andalusia and Murcia provinces.

Despite promises not to act without Portugal’s consent, the Spanish government has pressed ahead with a flurry of dam construction started in the 1980s.

Portugal is threatening to sue Spain in the U.N. International Court of Justice. But Portuguese fear the damage may already be done, pointing to stretches of the Guadiana where scattered pools are connected by trickles of water.

Of the 79 dams on the Spanish portion of the Guadiana, 18, including the huge La Serena dam, have been built in the last five years.

Baltanas says the lack of water in the Guadiana is the result of four years of drought on both sides of the border, not the dams. Over the last 12 months, rainfall on the Spanish watershed of the Guadiana has been 10% of normal.

“Just think that if the Guadiana did not have dams, the drought would be much more serious for the two countries,” Baltanas said.

Portugal also plans a huge dam on the Guadiana. But with little water flowing from Spain, it might not be able to fill the reservoir.

Talks are being held in an attempt to resolve the dispute, but little progress has been reported.

“The plan is a subversion of nature,” said Pedro Serra, president of Portugal’s Water Institute who is one of his government’s negotiators. “Sometimes I think they would be happy to see the Douro flowing the other way.”

Under Spain’s plan, 16 dams would be built along the Douro, which flows into the famous port wine-producing valley of Portugal.

The 10.5 billion cubic feet of water diverted annually would supply the Portuguese city of Oporto at the Douro estuary for 10 years and could reduce parts of the river to a mere stream, Serra said.

Ecologists say excessive damming has disastrous effects on rivers, their estuaries and coastlines.

Portugal’s Nature Protection League says less freshwater reaches the sea and concentrations of pollutants are higher, upsetting the balance of marine life in estuary breeding grounds. The reduced flow also lets salt water advance farther upriver, damaging freshwater life and the water table.

In addition, the league says, beaches are more prone to erosion because less sediment flows into the sea to replace sand carried away by ocean tides.

“To quantify the effects is, at the moment, impossible--nobody knows by how much the river levels will drop,” said Pedro Beja, a league spokesman.

In 1992, a study by Portugal’s National Civil Engineering Laboratories found the level of the Douro had fallen 20% in two decades due to increased water consumption and meager rainfall. The Tagus’ level had dropped 25% and the Guadiana’s 56%.

Beja said Spain’s intense use of irrigation--it is the world’s third-biggest water consumer per capita after the United States and Russia--has dried up as much as half of its underground water reserves.

Southern Spain and Portugal, which have prospered from a tourist boom, are now in the fourth year of serious drought.

“The lack of water in the south of the Iberian Peninsula is a limiting factor to sustainable economic growth,” said Serra. “We believe the Spaniards are risking this. Their grandiose projects are very dangerous.”

In both countries, cheap water leads to waste. Evaporation takes 40% of the water that Spain devotes to irrigation.

About half the water supply to Spain’s southern port of Cadiz leaks out of pipelines, while the city faces daily water cutoffs of up to 12 hours.

Spain is now using tanker trucks and ships to transport water to needy areas.