The Association of American Railroads reported a weekly increase of 1.5 percent in the overall volume of commodities delivered by rail for the week.
Total U.S. rail traffic of 562,094 carloads was up 3.1 percent when compared with the same time last year.
The AAR said Thursday 70 percent of the commodity groups delivered by rail in the United States posted increases year-on-year.
The increase in U.S. oil production puts a strain on existing pipeline capacity causing more refiners to rely on rail for crude deliveries, observers say.
The U.S. Energy Department's Energy Information Administration said in last week's short-term market report U.S. crude oil production in August averaged 7.6 million barrels per day, the highest monthly level since 1989.