After the completion of any such bridge and the approaches thereto, the Department of Highways shall provide for the collection of tolls until such tolls have been sufficient to reimburse the Motor License Fund for all costs, including the salaries of toll takers and maintenance and repair of such bridge during the period tolls are collected. As soon as the Motor License Fund has been reimbursed for all costs, any such bridge shall be freed from toll and shall become a part of the system of State highways, to be administered by the Department of Highways under the provisions of present or future laws governing State highways.