Decree-Law No. 47/94 establishing an economic and financial regime for public water use, managed by the Institute of Waters.

This Decree-Law establishes the principle whereby any water use is subject to an authorization and payment of a fee. Any type of public water use by different legal persons requires the payment of a fee called "use tax", for the protection and enhancement of this resource. Beneficiaries of waterworks for the regularization of surface and groundwaters, executed partially or totally by the State (Institute of Waters (INAG)), are subject to the payment of a "regularization tax". This Decree-Law establishes the financial regime for using public water resources. It defines the fees to be paid by water users for purposes of irrigation, captation, land occupation or other uses. It consists of 25 articles (dealing with the requirements to be met for fees payments) and 1 annex (establishing the value per any cubic meter of capted water).