Water Quality

ORS 468B.048
Rules for standards of quality and purity

  • factors to be considered
  • meeting standards


The Environmental Quality Commission by rule may establish standards of quality and purity for the waters of the state in accordance with the public policy set forth in ORS 468B.015 (Policy). In establishing such standards, the commission shall consider the following factors:


The extent, if any, to which floating solids may be permitted in the water;


The extent, if any, to which suspended solids, settleable solids, colloids or a combination of solids with other substances suspended in water may be permitted;


The extent, if any, to which organisms of the coliform group, and other bacteriological organisms or virus may be permitted in the waters;


The extent of the oxygen demand which may be permitted in the receiving waters;


The minimum dissolved oxygen content of the waters that shall be maintained;


The limits of other physical, chemical, biological or radiological properties that may be necessary for preserving the quality and purity of the waters of the state;


The extent to which any substance must be excluded from the waters for the protection and preservation of public health; and


The value of stability and the public’s right to rely upon standards as adopted for a reasonable period of time to permit institutions, municipalities, commerce, industries and others to plan, schedule, finance and operate improvements in an orderly and practical manner.


Standards established under this section shall be consistent with policies and programs for the use and control of water resources of the state adopted by the Water Resources Commission under ORS 536.220 (Policy on water resources generally) to 536.540 (Approval of voucher claims).


Subject to the approval of the Department of Environmental Quality, any person responsible for complying with the standards of water quality or purity established under this section shall determine the means, methods, processes, equipment and operation to meet the standards. [Formerly 449.086 and then 468.735]


Last accessed
Mar. 11, 2023