An analysis by Kull last year concluded that dangerously low lake levels seen recently were only partly due to a drought. A bigger cause, he found, was that dam operators were pulling in so much water that the flows exceeded the "Agreed Curve," a series of agreements meant to mimic natural flows and to ensure enough water reaches Egypt. Levels have risen this year.
The World Bank would not make officials available for an interview. But in a letter to Lori Pottinger of the International Rivers Network, a bank official cited an analysis indicating that Bujagali will not adversely affect Lake Victoria.
"In fact, in most years, lake elevation would be slightly higher" than that expected under the Agreed Curve, wrote Michel Wormser of the bank's Sustainable Development Department.
This is not the first Bujagali Falls dam proposal. In 2003, a different developer's plan, also with World Bank backing, was scrapped -- after years of planning -- in a corruption cloud.
The Bank Information Center, a watchdog group, asserts that the World Bank has focused on the Bujagali dam to the exclusion of other options, including smaller-scale hydro projects that could benefit many poor Ugandans who are not hooked up to the power grid.
"This project, given its long and tumultuous history, raises some serious questions about the priorities of financial institutions like the World Bank," said the center's Nikki Reisch. Even though construction is beginning, an independent World Bank inspection panel has not issued its own findings on questions raised by critics.
At one point, the price tag for the Bujagali dam was put at $550 million, and critics say the 40 percent increase to $772 million raises questions about its affordability, given that costs will be shared by the government and electricity users.
"Either way you're straining the taxpayer and the ratepayer," said Henry Bazira, Muramuzi's associate at the environmentalist association.
Ugandan officials did not respond to requests for comment, but a British consultant hired by the World Bank predicts that Bujagali will, in fact, cut electricity rates by up to 10 percent.
While environmentalists worry most about the hydrological effects, Nabamba Budhagaali has a different objection to the Bujagali dam. The aged spiritual leader of members of the Busoga ethnic group said a dam would disturb spirits that have resided there for generations.
"This is no kind of activity that can take place in that area," he said one afternoon between puffs on a large tobacco pipe during a religious ceremony. "Spirits were created from that spot. That is their home."
Budhagaali, whose spelling is a variation on the name of the falls, said the previous developer paid him to perform a ceremony to ask the spirits to move to a new home. But the ceremony never reached a conclusion, so to him the dam cannot proceed.
But the current developer says new ceremonies have begun under the auspices of the kingdom of the Busoga people. "I think it was a bit of an error or oversight to deal with an individual," said Kenneth Kaheru, deputy project manager. "Here [we are] dealing with the entire kingdom."
Besides flooding Bujagali Falls, the dam will destroy two other class-5 rapids in an 18-mile stretch that has increasingly lured whitewater rafters. As a result, the dam seems likely to hurt what has become Uganda's second-biggest tourist attraction after the mountain gorillas.
Nile River Explorers, the largest rafting outfit, sent 1,000 people down the river in July -- more than are allowed to see the gorillas in a month. Another stretch of river below the new dam will be open to rafters, and activities such as water-skiing are planned for the new reservoir.
But "you'll lose the heart of the rafting," said Jon Dahl, who owns Nile River Explorers and employs 80 people. "It's a bit sad."