The owner of any house, building or property used for human occupancy, employment, recreation, industrial use or other purposes, situated within the city, on any street, alley or right-of-way in which there is now a public gas main, is hereby required at their expense to install suitable facilities for the supply of gas thereto, and to connect such facilities directly to the public gas main if the use of gas is desired by the owner, provided the public gas main is within 300 feet of boundary of the property.