<p>An 81-year-old section of rail track in northern New South Wales that required freight trains to slow to a speed normally required in school-zones will be upgraded as part of a $200m upgrade by the Australian Rail Track Corporation (ARTC).</p> <p>Freight trains travelling between Grafton and Casino had been required to slow to 40 km/h for about 1.8 km as they travelled through the section. </p> <p>The ARTC said construction would begin in November on the $7.7m Leeville rail viaduct, which will cut about three and a half minutes from the freight time.</p> <p>Freighters will now be able to maintain a top speed of between 115 and 120 km/h along the corridor.</p> <p>The upgrade is part of work to speed up super freighter speeds between Sydney and Brisbane by almost four hours.</p> <p>The journey now takes 19 hr 22 min, but the upgrade work over the next three years should cut this to 15 hr 30 min.</p> <br />