65 ILCS 5/11-111-5
If a railroad or street railway company has tracks located upon, or across any street in such an improvement district, then, in estimating the cost of the work, the railroad or street railway company shall be charged with the cost of the fill upon that street or crossing in the amount that it would cost the railroad or street railway company to make an independent embankment of the same height to receive its tracks upon that street or crossing. However, any railroad or street railway company has the same right to build its embankment or make its proportion of the improvement as is allowed to individuals. If a railroad or street railway company fails or refuses to comply with the municipal ordinances in this regard, the tracks of the delinquent railroad or street railway company shall be a nuisance, all of the railroad or street railway company's rights upon that street or crossing shall be forfeited, and the tracks removed as the work progresses.
65 ILCS 5/11-111-5