The elder Redford said he was shocked when he learned that the Colorado River, which pierces through the Grand Canyon, only rarely ever reaches the sea. The river has run dry since 1998 after being tapped by the seven states that use its watershed.
Redford and his son produced a documentary about the problem, called "Watershed: Exploring a New Water Ethic for the New West."
The two were in Phoenix Saturday with several U.S. and Mexican conservation organizations at the Arizona Science Center for a celebration at which about 200 guests were to donate $500 apiece toward at least temporarily reviving the river's ecology and levels, The Arizona Republic reported.
They are raising funds to help support a deal between the United States and Mexico to raise regular flows of the Colorado River and to implement a one-time spring flood to mimic nature's way of churning up and reseeding riverside vegetation, the newspaper said.
The project will cost about $10 million and the government is covering about $3 million of it.