The Swedish Transit Authority (Trafikverket) announced completion of repairs early on Thursday morning. Train traffic is expected to take to the rails again later in the day, but at reduced speed, said spokesman Lennart Helsing.
"The trains are only allowed to go at 40 kilometres an hour," he told the TT news agency. "The Transit Authority together with the train operators are going to get the trains back on the rails in small steps, but service may still be limited during the day."
Last week, a cargo train jumped the tracks about 200 metres north of Södra Station in central Stockholm. The train then struck and damaged a pillar. Taking place at the very beginning of mid-week rush hour, the accident saw a commuter train stuck in the tunnel behind the freight train and caused major delays for the rest of the day.
Traffic was perturbed for several days as the emergency services cited the risk of potential collapse in the tunnel. In addition to the capital's extensive commuter rail traffic, long-haul passenger rail was also affected.
The convergence of tracks between Stockholm Södra and Central Stations is a bottleneck regionally and nationally. The critical stretch was upgraded by worried workers last summer, who told a local radio channel about their concerns that the kilometre-long convergence area had become a security risk. Ulf Olofsson, professor at the Royal Institute of Technology (KTH), backed up their assessment.
"If you have to secure the tracks in over 500 places on a one-kilometre stretch, that tells you that you have lost control over the tracks," Olofsson told Sveriges Radio (SR) at the time.
The accident came as little surprise to opposition MP Anders Ygeman, who sits on the parliamentary committee on traffic.
"If you can move the rails with just one hand, it isn't difficult to see that a several-tonne train can move it. This is the stretch of rail with the most traffic in the country," he told the TT news agency last week. "Which means it should be the best maintained, but clearly it isn't."
Infrastructure Minister Catharina Elmsäter-Svärd agreed, saying the government had assigned more funds to maintenance, but said a crucial problem was that engineers were awaiting the completion of the new Citybanan commuter rail line, designed to ease pressure from the stretch, before a complete overhaul.
Despite the heavy traffic and congestion risk on the tracks, Elmsäter-Svärd said she believed there was a low risk of accidents in central Stockholm.