1. No public road, highway or street shall be constructed across the track of any railroad corporation, nor shall the track of any railroad corporation be constructed across a public road, highway or street, nor shall the track of any railroad corporation be constructed across the track of any other railroad or street railroad corporation at grade nor shall the track of a street railroad corporation be constructed across the tracks of a railroad corporation at grade, without having first secured the permission of the state highways and transportation commission, except that this subsection shall not apply to the replacement of lawfully existing tracks. The commission shall have the right to refuse its permission or to grant it upon such terms and conditions as it may prescribe.

2. Every railroad corporation shall construct and maintain good and sufficient crossings and crosswalks where its railroad crosses public roads, highways, streets or sidewalks now or hereafter to be opened.

3. The state highways and transportation commission shall make and enforce reasonable rules and regulations pertaining to the construction and maintenance of all public grade crossings. These rules and regulations shall establish minimum standards for:

(1) The materials to be used in the crossing surface;

(2) The length and width of the crossing;

(3) The approach grades;

(4) The party or parties responsible for maintenance of the approaches and the crossing surfaces.

4. The state highways and transportation commission shall have the exclusive power to determine and prescribe the manner, including the particular point of crossing, and the terms of installation, operation, maintenance, apportionment of expenses, use and warning devices of each crossing of a public road, street or highway by a railroad or street railroad, and of one railroad or street railroad by another railroad or street railroad. In order to facilitate such determinations, the state highways and transportation commission may adopt pertinent provisions of The Manual on Uniform Traffic Control Devices for Streets and Highways or other national standards.

5. The state highways and transportation commission shall have the exclusive power to alter or abolish any crossing, at grade or otherwise, of a railroad or street railroad by a public road, highway or street whenever the state highways and transportation commission finds that public necessity will not be adversely affected and public safety will be promoted by so altering or abolishing such crossing, and to require, where, in its judgment it would be practicable, a separation of grades at any crossing heretofore or hereafter established, and to prescribe the terms upon which such separation shall be made. When a road authority lawfully closes or vacates a roadway which provided access to a railroad crossing, the state highways and transportation commission shall issue an order authorizing removal of the crossing by the railroad within thirty days of being notified of such action by the roadway authority or railroad.

6. The state highways and transportation commission shall have the exclusive power to prescribe the proportion in which the expense of the construction, installation, alteration or abolition of such crossings, the separation of grades, and the continued maintenance thereof, shall be divided between the railroad, street railroad, and the state, county, municipality or other public authority in interest.

7. Any agreement entered into after October 13, 1963, between a railroad or street railroad and the state, county, municipality or other public authority in interest, as to the apportionment of any cost mentioned in this section shall be final and binding upon the filing with the state highways and transportation commission of an executed copy of such agreement. If such parties are unable to agree upon the apportionment of the cost, the state highways and transportation commission shall apportion the cost among the parties according to the benefits accruing to each. In determining such benefits, the state highways and transportation commission shall consider all relevant factors including volume, speed and type of vehicular traffic, volume, speed and type of train traffic, and advantages to the public and to such railroad or street railroad resulting from the elimination of delays and the reduction of hazard at the crossing.

8. Upon application of any person, firm or corporation, the state highways and transportation commission shall determine if an existing private crossing has become or a proposed private crossing will become utilized by the public to the extent that it is necessary to protect or promote the public safety. The state highways and transportation commission shall consider all relevant factors including but not limited to volume, speed, and type of vehicular traffic, and volume, speed, and type of train traffic. If it be determined that it is necessary to protect and promote the public safety, the state highways and transportation commission shall prescribe the nature and type of crossing protection or warning device for such crossing, the cost of which shall be apportioned by the state highways and transportation commission among the parties according to the benefits accruing to each. In the event such crossing protection or warning device as prescribed by the state highways and transportation commission is not installed, maintained or operated, the crossing shall be closed to the public.

9. The exclusive power of the state highways and transportation commission pursuant to this section shall be subject to review, determination, and prescription by the administrative hearing commission, upon application to the administrative hearing commission by any interested party in accordance with section 621.040. Upon filing of an application pursuant to this subsection, the administrative hearing commission is vested with the exclusive power of the state highways and transportation commission otherwise provided in this section, with reference to matters reviewed, determined or prescribed by the administrative hearing commission.