As nations fight over oil, a new global struggle has emerged, fueled by a different kind of scarcity — clean water.

World leaders have not yet effectively tackled problems that include worsening pollution traveling in streams that see no borders and changes in climate that have prompted rain to fall at the wrong place and at the wrong time.

“The global water crisis is the twin sister of global warming,” said filmmaker Irena Salina, whose latest documentary, “Flow,” raises concerns over the shortage of clean water. The precious drops could one day be traded like liquid gold, she predicted.

The French director spent five years probing the politics of the impending crisis and found alarming trends: privatization by multinational companies, as well as beverage giants that are bottling fresh water from the world’s free reserves.

The fruit of her labor is a celluloid chronicle of the heated debates and fights among European and American water companies, helpless villagers, activists and scientists from Bolivia, India, South Africa, Canada and the United States over water.

Intrigued by a 2002 Nation magazine article titled “Who Owns Water?,” which discussed the debates over water privatization in New Orleans, Salina grew increasingly concerned that her toddler son might inherit a dirty and dangerous world.

The journalist-turned-director went behind the scenes at the World Water Forum conference in Kyoto in 2003, showing negotiations between lobbyists and policymakers over the resource.

One of the water wars the film followed was the 2000 privatization of the municipal water supply of the Bolivian city of Cochabamba, which lies in a semi-desert region. The issue was contentious in a country where nearly 1 out of every 10 children will die before the age of 5 from a lack of clean drinking water, according to the Democracy Center in Bolivia.

The World Bank would not renew a $25 million loan to the South American country unless it allowed the water company Bechtel to privatize Cochabamba’s water, according to Jim Shultz, executive director of the Democracy Center in Cochabamba.

But the Bolivian villagers soon grew disillusioned as they found out the new deal was costly and the quality of the treated water was inferior. Like the poor in South Africa, where global water giants took over public water supplies, Salina’s camera recorded what happened if they couldn’t pay: Their public water pumps were either chained or received an intermittent supply of water.

“It was inspiring to learn that the most effective way to implement change around water issues, both here in the U.S. and abroad, are individual, community-based initiatives,” Salina said. When Coca-Cola set up new factories in India’s Kerala and Mehdiganj, which depleted local ground water, the camera followed angry farmers who staged months of sit-in protests outside the soda factories until they closed down. (The film also showed Indian villagers refusing to accept bags of cadmium-rich waste sludge Coca-Cola presented as “fertilizer.”)

Those who can pay for clean water may not know what goes into the making of it. Environmentalists accused water-bottling companies of taking fresh water from many American towns and depleting local resources. One such conflict was the 2001 lawsuit, Michigan Citizens for Water Conservation v. Perrier/Nestlé. Residents of Mecosta County, in central Michigan, alleged that Perrier (now Nestlé Waters North America) privatized the water supply under the guise of “reasonable use.” Disgruntled homeowners showed the director how the rapid pumping had drained surface water and caused the soil around their houses to subside.

The film also interviewed many scientists and water experts who dispelled myths surrounding bottled water. They argued that packaged water is less regulated than public water and thus contained contaminants. The making of plastic bottles has also heightened the consumption of oil and many of the containers ended up in landfills.

In a hilarious sequence, American college students staged “blind” water tests on campuses where many youngsters realized tap water tasted no different from water that came from far-flung places tagged with fancy labels.

The uphill battle can be partly resolved through some creative solutions, experts interviewed in the film showed. For instance, scientist Ashok Gadgil of the Lawrence Berkeley National Laboratory devised ultraviolet light tubes to kill pathogens in water and transferred that technology to Indian villages. The low-cost device curbed malaria and other water-borne diseases, and an overjoyed chicken farmer grinned on screen because his poultry was no longer sick. Back in the United States, the film revealed that more and more homeowners have installed rainwater-collecting devices on their rooftops to save water.

The film begins and ends with the hauntingly beautiful ritual of death at India’s Ganges River. The film’s goal, the director said, is to stress that water is the precious unifying element of all humanity. “We all want it more than anything else in the world,” Salina said. “This universal concept became the heart of my film.”

Salina hopes her message can help herald a new ethic: Just like the air we breathe, water transcends barriers and thus should be shared, and not to be held in the hands of a powerful few, she said.

“Flow” is being shown at the Landmark E Street Cinema, 555 11th Street NW; 202-452-7672.