The Sound Transit board of directors today took a major step towards delivering the Sounder commuter rail expansions that voters approved in 2008 by authorizing the purchase of rights to four additional south line Sounder round trips.

The $185 million purchase agreement with Burlington Northern Sante Fe Railway enables the regional transit agency to incrementally expand its commuter rail service from nine to 13 round trips a day, with the first new round trip starting as soon as 2012. The expanded service will add four peak direction, peak hour trains to the Seattle-to-Tacoma Sounder schedule, with flexibility to run reverse commute and midday service based on ridership demand.

The easement rights for the four additional trains grant use of the Seattle-Tacoma railway in perpetuity.

The four perpetual easements purchased from Burlington Northern will expand Sounder service on a staggered schedule, with the first additional train beginning operation in July of 2012, followed by a second in the fall of 2014, a third in the summer of 2015, and a fourth the following year.

For more information, visit http://www.soundtransit.org/documents/pdf/about/board/resolutions/2010/Reso2010-14.pdf .