605 ILCS 5/6-113

In each road district comprised of a single township, the township clerk shall be ex-officio the clerk for the highway commissioner.

In each consolidated township road district the road district clerk shall be selected by the highway board of auditors of such district from its membership.

In each other road district there shall be elected a road district clerk except as is provided in this Code for county unit road districts and for municipalities that have been created a road district.