The Government had announced a $5 million boost from the Provincial Growth Fund to get the line open again to meet transport demands from the so-called Wall of Timber from northern Hawke's Bay and east coast forestry harvesting over the next few years.
The line was "mothballed" by Government-owned KiwiRail in October 2012, six months after a washout near Waikokopu closed the Wairoa-Gisborne sector.
But plans for reopening the line between Napier and Wairoa hit another snag with a washout after heavy rain in the first week of September.
Forty-five metres of track was left swinging in the air near the Maungaturanga Viaduct, north of the State Highway 2 and railway township of Raupunga.
Clarke said in October a detailed assessment of the site showed it was a more complex situation than initial inspection indicated, and fixing the slip would delay the reopening of the Wairoa to Napier line.
KiwiRail's preferred option was to rebuild the embankment, removing a significant volume of slip material and backfilling on the site.
"While this setback is unfortunate we remain committed to reopening the rail line for forestry," Clarke said at the time.
He added it was working with other stakeholders and forestry owners to see if there were other options for rail freight while work continued at the washout.
"September's event will not stop what is an important freight connection for the region," he said.
"Taking logs to the port (of Napier) by rail will reduce carbon emissions, take trucks off the road and provide an efficient service for forestry owners."