The most powerful documentary I've seen at Sundance is Trouble the Water, a take on Hurricane Katrina and its aftermath unlike anything I've seen. Combining footage shot by longtime Michael Moore collaborators Carl Deal and Tia Lessin with amateur video footage shot from the eye of the hurricane by New Orleans resident Kimberly Rivers Roberts (who received director of photography credit) the film shows the impact of Hurricane Katrina and what happened to the city's poorest residents both during and after the storm.

Roberts, who bought a camcorder off the street for $20 a week before the storm hit, intending to use it only to shoot family gatherings, captured the residents of the 9th Ward, one of the hardest-hit areas of New Orleans, as those who could got out and those who couldn't battened down the hatches in preparation for the storm. Roberts and her husband Scott were among those who were unable to evacuate the city because they had no transportation and no money to go anywhere. The mayor of New Orleans ordered the city evacuated, but there was no public transportation organized to get out those people who didn't have the means to do so on their own.

Roberts kept filming as the storm's intensity increased. When the levees (located just a few blocks away from her neighborhood) broke under the weight of the storm, the water rushed in, forcing Roberts, her family, and neighbors they took in to take shelter in the attic of her house. But the flood waters kept rising, trapping them inside, and there was no National Guard or Coast Guard attempt to rescue the stranded. During the most harrowing part of the film, we hear a call to 911begging for rescue, while the dispatcher just keeps saying there are no rescue vehicles available, and the police are not coming out "until the weather clears."

They finally manage to escape with the aid of a neighbor, who braves the floodwaters the police and National Guard refuse to venture out in to save his neighbors one at a time, using a punching bag and later a boat that floats by to move people to higher ground. In another incredible bit, we see a vacant military base being guarded by a few soldiers, who have been ordered not to allow displaced residents to take shelter there, even though the base has hundreds of rooms not being used. When a group of residents, including women and small children, came to the base seeking shelter, the soldiers turned them away with M-16s in hand; they were later given a commendation for their "bravery" in protecting the government's property.

Roberts keeps her camera rolling in the weeks that follow, showing the plight of the residents who have lost everything they own, the fight to get the $2000 per household payout from FEMA that's supposed to allow displaced residents to rebuild, and the Roberts' move to Memphis to start a new life -- and then back to New Orleans when they realize what they really want is to help rebuild their hometown.

As shocking as the story is, Trouble the Water is as much a story of hope and inspiration as it is about anger. Roberts wrote several rap songs for the film under the moniker "Black Kold Madina," and one of the most powerful moments in the film is a segment where she spontaneously sings along with a recording of one of her songs, "Amazing," which tells the story of her life. The song is incredibly poetic, powerful and insightful, and the passion with which Roberts sings about her hope, her strength, and her determination not to give up in the face of overwhelming adversity, is the heart and soul of this film. People all around me were crying by the end of that song, and the audience spontaneously burst out into cheers and applause when it ended.

Trouble the Water won the Grand Jury Prize for documentary at Sundance last night, and after seeing it, it's easy to see why. Watching the film, you feel the fear and helplessness, the anger and sense of abandonment, and most of all the hope of Roberts and her neighbors. The film has yet to be picked up for distribution, but hopefully with the Grand Jury Prize under its belt, some smart distributor will take notice and make sure the film gets seen by a wider audience. It's only January, and we aren't even past this year's Oscars yet, but I'll go out on a limb right now and say that I fully expect to see this film nominated for an Oscar next year, and if that happens, it will absolutely deserve to be there.