After many of his requests were repeatedly rejected by the Engineers Office of Argentina (then directed by Guillermo White), finally the Government granted D'Abreu's company, "Abreu, Torres y Cía", a concession to build and operate a railway by Law N° 2097 on September 29, 1887.

[6] The company was registered in May 1889 and assumed concessions for lines from the port of Bahía Blanca in the south of Buenos Aires Province to Río Cuarto in the joint with Andean Railway and Villa Mercedes in the joint with BA & Pacific, via cities of General Acha, La Verde, Toay and Victorica, all of them in La Pampa Province.

Architects Alejandro Christophersen and Carl August Kihlberg were hired by the Hume Brothers (that worked as contractors for several railway companies including the BB&NWR) to design the Bahía Blanca terminus station, which was opened in 1891.

[6] On 29 January 1891, then president of Argentina Carlos Pellegrini promulgated a decree that allowed the company to build the Bahía Blanca-Bernasconi section.

That same year the National Congress promulgated Law N° 4481 that committed BB&NWR to build new branches to Nueva Roma and Catriló.