The Mexican environment minister has admitted that the nation's water problems are more serious than thought, with grave problems of desertification and pollution. Mexico has less drinking water - per capita - than the desert nation of Egypt, 60 percent less than 50 years ago, 73 percent of its supply contaminated and a danger to public health, and 93 percent of its rivers polluted, according to the government itself.

Even President Vicente Fox has referred to Mexican rivers as "a lethal source of sickness" after "decades of having been overexploited, without planning, without sense," and recently declared water as an issue of national security. Only 14 percent of the nation's municipal and industrial wastewater is currently treated.

The national water commission said that at least $30 billion must be invested in the next decade to halt the contamination and to treat enough water to keep pace with people's needs. However, Mexico does not even currently have sufficient funding for its present water-treatment facilities.