Underground utility lines crossing highways, frontage roads, and intersecting roads and streets within the right of way may not use the opening of a drainage structure as a means of obtaining the crossing, except that underground crossings may be placed in the proper depth trench under box bridges without floors and under bridges provided such locations will not be so near piers, piling or foundations that damage may occur or the line conflict with bridge supports, abutment fill slopes or slope paving.
37 Miss. Code. R. § 1-7501-04001-200