Ind. Code § 8-6-1-1

Sec. 1. The Indiana department of transportation (referred to as "the department" in this chapter) shall carefully investigate and examine all the highway crossings of railroads in this state and to make or cause to be made files and numbers of the highway crossings, so that the crossings may be known and designated by mileposts or otherwise, and referred to and considered, from time to time, as may be necessary to carry out this chapter.