The service pipe between the main and the stop cock at the curb, including stop cock and box, shall be kept in repair and protected from the frost by the Commissioner of Water, except that in case any service pipe, corporation cock, stop cock, valve or box is damaged, broken, removed or covered with pavement, flagging, cement sidewalk or any other way, by or on account of the neglect or carelessness of any plumber, sewer builder, contractor or any other person, occupant or owner of premises, all necessary repairs shall be made by the Commissioner at the expense of the party who caused the same. The service pipe from the stop cock at the curb into the building, and all fixtures connected therewith, must be kept in good repair and protected from frost by and at the expense of the occupant or owner of the premises.