Just 10 kilometers from where the Nile begins its journey north, Bujagali Falls, with its wild stretches of nature, may soon become the site for East Africa's largest foreign investment project ever. AES Corp., a company based in Arlington, Virginia, that has grown into the world's largest independent power producer, has struck a $500 million deal with the Ugandan government to build a massive dam near Bujagali that would greatly expand power capacity for the country, where less than 5 percent of the 22 million resident have electricity.