Hump yards
The number of hump yards operating in North America has dropped precipitously over the decades. Today there are 36 active hump yards operated by the big six Class I systems and terminal and switching railroads. That’s down from 59 in 2002, 72 in 1993, 122 in 1985, and 152 in 1975.
Yet hump yards, which use gravity to classify freight cars, remain enormously important to the carload network. They are the most efficient way to classify high volumes of carload traffic into destination-based blocks and, ultimately, merchandise trains. The typical hump yard classifies between 1,500 and 3,000 cars per day.
Today’s hump yards are computer controlled. As a train is slowly shoved over the hump, individual cars or cuts of cars are uncoupled and roll downhill toward the classification bowl. Switches are lined automatically for the correct bowl track, which typically represent a single destination. Retarders regulate the speed of cars as they descend the hill, taking into account factors such as weight, weather, wind direction, and the number of cars that already occupy the bowl track.
Although hump yard design can vary somewhat, they all follow the same operational pattern: Road freights arrive at a receiving yard. A yard crew shoves the train over the hump, with cars flowing to the proper tracks in the classification bowl. At the pulldown end of the bowl, yard crews combine blocks from various tracks into an outbound train, which is moved to the departure yard. Cars typically spend 24 hours in a hump yard.
The number of hump yards has declined for a variety of reasons. Among them:
- The long-term decline of loose-car railroading and the rise of intermodal and other unit trains that operate from point to point and do not require classification en route.
- Mergers of Class I railroads into today’s megasystems, which consolidated traffic flows and allowed railroads to rationalize duplicate facilities.
- A greater emphasis on reducing the need for classification by pre-blocking cars at origin and block-swapping en route, which siphoned volume away from some hump yards, leading to their outright closure or conversion to flat-switching facilities.
- As retarder systems became outdated and switching volume dwindled at some older yards, railroads in some cases could not justify the expense of modernizing hump yards.
Hump yards are symbols of big time, heavy duty railroading — and they’re not going away anytime soon. “There is nothing wrong with a hump yard. It’s the most efficient way to handle 1,800-2,000 cars a day,” Union Pacific CEO Jim Vena says. “There is nothing better. It’s low cost, it works well.”
Class I railroads have invested in hump yard modernization projects in recent years, including at Union Pacific’s Englewood Yard in Houston; Norfolk Southern’s Brosnan Yard in Macon, Ga., and Norris Yard in Birmingham, Ala.; and BNSF Railway’s Northtown Yard in Minneapolis and Argentine Yard in Kansas City, Kan.
North American Hump Yards Operating in 2024
Alton & Southern
- Gateway Yard, East St. Louis, Ill.
Belt Railway of Chicago
- Clearing Yard, Chicago, Ill.
BNSF Railway
- Argentine Yard, Kansas City, Kan.
- Barstow, Calif.
- Cherokee Yard, Tulsa, Okla.
- Galesburg, Ill.
- Hobson Yard, Lincoln, Neb.
- Northtown Yard, Minneapolis, Minn.
- Pasco, Wash.
- Tennessee Yard, Memphis, Tenn.
Canadian National
- MacMillan Yard, Toronto, Ontario
- Symington Yard, Winnipeg, Manitoba
- Kirk Yard, Gary, Ind.
- Harrison Yard, Memphis
Canadian Pacific
- St. Paul Yard, St. Paul, Minn.
Conrail
- Oak Island Yard, Newark, N.J.
CSX Transportation
- Avon, Ind.
- Queensgate Yard, Cincinnati, Ohio
- Radnor Yard, Nashville, Tenn.
- Selkirk, N.Y.
- Waycross, Ga.
Indiana Harbor Belt
- Blue Island, Ill.
Norfolk Southern
- Moorman Yard, Bellevue, Ohio
- Brosnan Yard, Macon, Ga.
- Conway, Pa.
- DeButts Yard, Chattanooga, Tenn.
- Elkhart, Ind.
- Norris Yard, Birmingham, Ala.
Terminal Railroad Association of St. Louis
- Madison Yard, Ill.
Union Pacific
- Bailey Yard, North Platte, Neb.
- Davidson Yard, Fort Worth, Texas
- Davis Yard, Roseville, Calif.
- Englewood Yard, Houston, Texas
- Livonia, La.
- North Little Rock, Ark.
- West Colton, Calif.
