Same River Twice (1997)

Four friends return to the river where they worked together for years as whitewater guides. They soon discover that their paths have gone in different directions. But, later in the trip, when they're in danger of losing people in a huge rapid, they must work together to execute a daring rescue. Ultimately, as they are forced to confront one another, the river, and the past--they learn that a true friend may well be reckoned the masterpiece of nature.