The department may bring actions, suits or proceedings as in its judgment may be necessary and proper to enable it to perform any of the duties imposed upon it by the provisions of article 15 except section 15-1713 thereof as amended or to prevent the violation by any person or public corporation of any of the provisions thereof; and may defend such actions, suits or proceedings as may arise through the performance of any duties or functions imposed upon it by the provisions of article 15 except section 15-1713 thereof, as amended.