If, upon the division of a borough into wards or the creation of a new ward, the number of members of council cannot be equally divided among the wards of the borough, it shall be lawful for council to increase the number of council members to and not exceeding a number that will enable equal apportionment of the members among the several wards of the borough. If a borough is first divided into wards, the number of members of council provided for a ward may not exceed two.
Pennsylvania Legal Code