The railroad was built with the primary objective of providing coal to the Kintigh Generating Station, also known as the Somerset Power Plant, a 675 megawatt coal-fired power plant located in Somerset, New York.

From Newfane, New York, the SOM sweeps off the IRC (abandoned in 1937) to the Hojack Line in Appleton, New York (Township of Newfane, Niagara County, NY), to West Somerset in the Town of Somerset.

Unit coal trains leaving from Youngstown, Ohio, run to Erie, Pennsylvania, followed by Buffalo, then north to the Niagara Branch, where they swing off onto the Lockport Subdivision, and finally in Lockport onto the Somerset Secondary.

[1] The Somerset plant closure was a direct result of Governor Andrew Cuomo's plan to reduce carbon emissions in New York state.

Prior to line abandonment, all Somerset rail cars were collected by CSX and sent to scrap, with a few remaining in other mixed services.