Shamokin Township is a township in Northumberland County, Pennsylvania, United States. The population at the 2010 Census wa…Shamokin Township is a township in Northumberland County, Pennsylvania, United States. The population at the 2010 Census was 2,407, up from 2,159 at the 2000 census. The city of Shamokin does not sit within the boundaries of Shamokin Township. but inside Coal Township bordering it to the south.