It's safe to say already that 2015 will be a year of upheaval for Georgia's transportation department.

As lawmakers weigh a landmark proposal to raise new cash for infrastructure and transportation leaders eye a range of new projects, word comes today that Department of Transportation commissioner Keith Golden is stepping down. Spokesman David Spear said his last day will be Jan. 31.

Golden has led the agency - and the reins of a roughly $2 billion annual budget - since early 2012. Here's some background from our story on his appointment then:

Until then, Golden oversaw about 350 employees in a division working on road signs, traffic alert systems, roadside grass maintenance and patching up pavement, he said, far short of the 4,500 employees in the DOT's staff. He did not hold one of the top positions such as deputy commissioner or chief engineer.

Since he took the helm, he's faced increasing fiscal challenges with a tight budgets and a growing list of transportation priorities. He also took some heat for his role in the disastrous state response to last year's Jan. 28 snowy weather, and was part of the team assigned to make sure it never happened again.

Gov. Nathan Deal's office had no immediate comment on Golden's departure. Expect plenty of attention on the bid to succeed him.

Our friends over at Peach Pundit got hold of Golden's farewell letter. Here's a passage:

The State Transportation Board is doing a great job in working with the State Legislature and the Governor's Office to attempt to identify adequate future transportation funding.  Many on our staff have spent the last few months making a strong business case for the critical need.  Transportation funding is going to be one of the primary topics during the legislative session and that is one of the primary reasons I thought it would be the proper time for me to retire.  Many of you know that I had met my retirement eligibility last year.  I wanted to be a participant in the Joint Transportation Infrastructure Study Committee to contribute what I could.  The Study Committee completed their work on the last day of December with a menu of options for consideration.  Knowing that I would potentially retire this year, I did not think it would be appropriate for me to overly active in seeking the much needed funding.