MELBOURNE (Reuters) - Australian Rail Track Corp (ARTC) said on Wednesday it has partially reopened the Hunter Valley coal rail lines to Newcastle, the world’s biggest coal export port, after nearly a week of heavy rain stopped in New South Wales state. Coal rail deliveries to the Port of Newcastle, which last year shipped 158 million tonnes of coal, were suspended on Thursday when relentless rainfall began in New South Wales, triggering the worst floods in at least 50 years. “Coal services have resumed in a limited capacity following minor restoration works, which were carried out during a six hour work window on Wednesday morning after flood waters receded at Sandgate,” the ARTC, which runs the rail network, said in a statement. It has reopened limited operations between Newcastle and Maitland and said it would continue to assess conditions as it progresses toward a full return to service. The network between Narrabri North and Moree remains closed, it said. The Hunter Valley rail network serves mines run by BHP Group, Glencore Plc, New Hope Corp, Whitehaven Coal and Yancoal Australia, among others. The Port of Newcastle, which had to slow ship movements earlier in the week, said on Wednesday it was continuing to operate.