Construction crews are working on improvements to 12 miles of roadway on Route 2 between Passadumkeag and Lincoln, according to the Maine Department of Transportation. The work begins about one mile south of the Passadumkeag-Enfield town line and extends north to the intersection of Route 2 with Penobscot Valley Avenue and the Access Road in Lincoln. The project includes drainage and safety improvements and paving. The Lane Construction Corp. of Meriden, Conn., and Bangor is doing the work under a contract of almost $1.8 million. Work is expected to be completed by late September.