In 1996, Cornerstone and another private equity group acquired Tidewater Barge Lines, Inc. Tidewater is the dominant barge transportation line on the Columbia/Snake river system, one of America’s most important barge river systems. Tidewater transports approximately 85% of the grain products, 100% of the clean petroleum products, and 50% of the containers transported on the Columbia/Snake river system. In 2005, Tidewater was sold to a financial sponsor.