Miss. Code § 65-23-11
The Mississippi State Highway Commission may, when in its opinion the best interest of the state requires, contribute such an amount of the cost of the construction of such bridge or bridges as it may determine would be to the best interest of the State of Mississippi when such bridge forms a part of or a continuation of the state highway system, or is so connected with the state highway system through the streets of a municipality leading from the approaches of such bridge to the state highway system, and may incorporate any such toll bridge into the state highway system. Such State Highway Commission may, in whole or in part, maintain such bridge as a part of the state highway system, or may leave the maintenance of such bridge to the municipality or other political body acting jointly with such State Highway Commission in the financing and operation of such bridge. In event that the State Highway Commission shall contribute any sums of money towards the creation or acquisition of such bridge and the approaches thereto, said State Highway Commission may or may not, in its discretion, require the repayment of such funds through tolls collected, together with interest on such moneys so advanced or donated at a rate, to be determined by said State Highway Commission, not to exceed said amount of six and one-half percent (61/2%).
Miss. Code § 65-23-11