For the purpose of financing the cost or expense, or its share of the cost or expense, of constructing, reconstructing, extending, improving or acquiring a sewer, sewer system or sewage treatment works, any city of the first class may issue non-debt revenue bonds secured solely by a pledge, in whole or in part, of the annual rentals or charges for the use of such sewer, sewer system or sewage treatment works. Said bonds shall not pledge the credit, nor create any debt, nor be a charge against the general revenues, nor be a lien against any property of the city, but shall be a lien upon and payable solely from the annual rentals or charges for the use of said sewer, sewer system or sewage treatment works.

Whenever any city has enacted an ordinance or resolution imposing a sewer rental or charge upon properties to be served by such sewer system or sewage treatment works when the same is completed, and has pledged sufficient of the revenues to be derived therefrom for the payment of interest and sinking fund charges on such non-debt revenue bonds, it shall have power to authorize the issue and sale of such non-debt revenue bonds, from time to time, as the work of construction proceeds, and sufficient additional non-debt revenue bonds, as may be necessary, may be issued and sold to provide for the interest and sinking fund charges accruing thereon, until said sewer system or sewage treatment works has been completed and has been in operation for not exceeding one year, in order to provide sufficient revenues until such time as sewer rentals or charges may be collected from the owners of properties being served.

Nothing in this act shall be construed to abridge or restrict, or in any way impair the right of any city of the first class to create indebtedness in accordance with existing laws.