2006 New York Code - Contracts.

 
    §  118-a.  Contracts.  Any municipality authorized herein to develop a
  supply of water for sale is hereby empowered to enter into contracts for
  such periods as it may deem necessary but not in excess of forty  years.
  Such  contracts may contain provisions for establishment and revision of
  charges for water, for adjudication of disputes and,  in  return  for  a
  guaranteed  minimum consumption by the purchaser, for the application of
  conservation methods by the  seller  when  necessary  to  preserve  such
  excess.