Sec. 4. The average normal water level shall be determined by means such as the following:
(1) Old surveys.
(2) Testimony of old inhabitants.
(3) The extent to which drainage and other artificial causes have increased or decreased the natural ground water of the area and affected the water levels of the lake.
(4) Water level measurements made by the following:
(A) The United States Geological Survey.
(B) The department.
(C) Other agencies.
(D) Individuals.
(5) Any other pertinent surrounding facts or circumstances.