§ 56-a. Use by the state, individuals and corporations outside corporate limits. 1. Any city having a population of fifty thousand or less may sell to a public or private corporation, or to an individual, the right to make connection with its sewer system for the purpose of discharging sewage therein from outside the city limits, and fix the term, consideration and conditions therefor. The board shall not sell nor permit the use of its sewer system under this section if thereby such sewer system will be rendered inadequate for the city or its inhabitants. The term "public corporation" shall mean a public corporation as defined in section three of the general corporation law.

2. Any city having a population of fifty thousand or less may contract with the state of New York or with the state authority having control and supervision of any state institution, and the state of New York or the state authority having control and supervision of any state institution may contract with the board of sewer commissioners of any such city, to provide sewerage and sewage disposal facilities for the conveyance, treatment and disposal of the sewage of such state or state institution either within or without the corporate limit of said city on such conditions and conveying such powers to the state or such state authority and for such consideration and such period of time as said sewer commissioners and the state of New York or such state authority may agree.

3. Any city having a population of fifty thousand or less may contract with the United States of America or with the federal agency, administration or authority having control and supervision of any federal institution or installation to provide sewerage and sewage disposal facilities for the conveyance, treatment and disposal of the sewage of such federal institution or installation either within or without the corporate limits of the city on such conditions, for such consideration and for such period of time as said sewer commissioners and the United States of America or such federal agency, administration or authority may agree.