(a) Due to a determination by the Environmental Quality Commission to establish a Total Maximum Daily Load for a body of water under the Federal Water Pollution Control Act (33 U.S.C. 1313);
(b) Due to a declaration of a ground water management area under ORS 468B.180; or
(c) When an agricultural water quality management plan is otherwise specifically required by state or federal law.
(2) For an area whose boundaries have been designated under this section, the department shall develop and carry out a water quality management plan for the prevention and control of water pollution from agricultural activities and soil erosion. The department shall base the plan and rules adopted to implement the plan upon scientific information. [1993 c.263 §3; 2001 c.594 §1]