1. For the purpose of paying its share of the cost of any of the expenditures herein authorized, exclusive of annual cost of maintenance, any city, town or incorporated village which may have entered into a joint contract, as provided in sections 71.400 to 71.430, may become indebted to an amount exceeding, in any year, the income and revenue provided for such year, the amount of such indebtedness, including existing indebtedness at the time of incurring the same, not to exceed, in the aggregate, five percent on the value of the taxable property in said municipality, to be ascertained by the assessment next before the last assessment for state and county purposes previous to the incurring of such indebtedness.

2. To incur such indebtedness, the council, board of aldermen or board of trustees of the contracting parties, each acting separately, shall order that the question be submitted to the voters to determine whether or not bonds shall be issued by said municipality, as herein authorized. The notice shall state the amount of indebtedness to be incurred and of the increase in the rate of taxation, if any, necessary to discharge such indebtedness in the manner provided by law.