Miss. Code § 65-17-203
The duties of the county engineer shall be to prepare all plans and estimates for the construction of bridges and superintend their construction, to make all estimates and plans of work to be done in the construction and maintenance of roads and superintend the work, to go over the report to the board of supervisors what work should be done to properly upkeep and maintain all roads and bridges in the county, and to check over and report to the board of supervisors on all estimates before payment by the board of supervisors of all work done on public roads.
The engineer may be required to furnish plans and estimates, and may superintend the construction of any road under the supervision of the state highway commission, if the highway commission may so elect. The purpose of this section is to provide a means whereby the board of supervisors and the highway commission may co-operate in such work, when same can be done, and reduce the expense of construction of any road.
Miss. Code § 65-17-203