The people of the state of Washington recognize that it is in the public interest to conserve and use wisely the public surface and ground waters of the state in a manner that will assure the maximum benefit to the greatest possible number of its citizens. The maximum benefit to the greatest number of citizens through the use of water for the irrigation of agricultural lands will result from providing for the use of such water on family farms. To assure that future permits issued for the use of public waters for irrigation of agricultural lands will be made on the basis of deriving such maximum benefits, in addition to any other requirements in the law, all permits for the withdrawal of public waters for the purpose of irrigating agricultural lands after *the effective date of this act shall be issued in accord with the provisions of this chapter.