The scope of the work will include replacing up to 90,000 crossties and 60,000 tons of ballast, in addition to crossing surface upgrades and rail alignment work.
Port staff will open bids on Tuesday, June 12.
The port district purchased the 134-mile Coos Bay rail line in 2009, following its closure in 2007. The rail line is undergoing nearly $30 million in repairs and re-opened to partial service in October 2011. The railroad operated by ARG Trans as the Coos Bay Rail Link - CBR has restored freight rail connections between manufacturing companies in Coos, western Douglas and western Lane counties to the rail system. Full service is expected to be restored in late 2012.