The county commissioners may originally locate, lay out and establish in whole or in part, relocate, straighten, widen, extend, alter and open, construct and improve roads not parts of the system nor deemed main thoroughfares, upon parties interested in paying or securing to be paid the proportion of the cost of the original construction and improvement as the commissioners may deem just, which may not be less than one-fourth of the cost.
16 Pa.C.S. § 16923