About midway through Jefferson Parish, the Orleans-Kenner interurban (or O-K Line) passed through the village of Harahan. The company's car barn and power station were located here as well as one of its busiest stops. "Harahan City," as the subdivision was promoted at the time, was laid out in 1914 near the railyards bearing the name of J. T. Harahan, president of the Illinois Central Railroad.
The Illinois Central and Southern Pacific Railroads maintained a ferry crossing between Harahan and Avondale to carry their railroad cars across the Mississippi River. To reach this ferry, the rail cars traveled up an incline that brought them over the river levee. Once the O-K Line began operating, the Illinois Central had to raise this incline so that the O-K Line cars could pass underneath and travel to Kenner and beyond. After a delay of four months, service was extended from Harahan to Kenner on July 3, 1915.
The O-K Line was a great benefit to Harahan and the surrounding areas along present-day Jefferson Highway. At a time when good roads in rural Jefferson Parish were hard to come by, the O-K Line provided a cheap and reliable way for the farms and dairies of the area to get their goods to market. The railroad workers and their families could reach Canal Street in less than an hour without a single transfer. Also, the O-K's power station provided electrical service to the residents between Kenner and Shrewsbury.
The paving of Jefferson Highway along the O-K tracks between Kenner and New Orleans during the mid-1920s contributed to a rapid decline in patronage. Once Jefferson Highway and South Claiborne Avenue were connected in September 1928, one could travel quickly by automobile along the exact route taken by the interurban line. After a series of cutbacks, service was discontinued on December 31, 1930.
Today, there is little evidence of the O-K Line's former presence in Harahan. The S-curve on Jefferson Highway dates to the original plan of the subdivision providing room on either side of the line's right-of-way through the town center. There is also a street intersecting Jefferson Highway near Colonial Club Drive called "O K Avenue" that is derived from the name of the line.