037-1 Wyo. Code R. § 1-9
a. W.S. 41-3-612 allows that water uses may be rotated with the approval of the hydrographer commissioner or water commissioner. The purpose of this statute is to bring about a more economic and efficient use of water. Rotation is accomplished in accordance with the specific rules set out in Chapter V, Section 23 of these regulations. The usual practice is to divert the collective supply available in priority to the appropriations to be rotated for irrigating the lands under each appropriation more quickly and efficiently. After the first irrigation, the diversion is closed down and the collective supply is used for the irrigation of the lands under another appropriation, etc. The rotation must be accomplished in such a way that there is no injury to other appropriators from the same source of supply. This is done by establishing a definite rotation period for irrigation of the land under each appropriation based on the number of acres irrigated by each appropriation plus an adjustment in time of irrigation to account for the differences in return flow patterns from the irrigation for each appropriation.
b. For example, assume that land under two appropriations to be rotated have the same general cropping pattern, soil characteristics, slope of land, etc., and therefore have similar return flow patterns, and that each appropriation is for one cubic foot per second for irrigation of 70 acres. Further assume that the one 70 acre tract can be irrigated in five days with the collective supply from both appropriations. The total supply of two cubic feet per second would be applied to the one 70 acre tract for a five day period and would then be shut off from these lands and be diverted at the same rate to the other 70 acre tract for another five day period.
c. If we assume the same general conditions are present except that the two appropriations are for 70 acres and for 140 acres, then water would be allowed for diversion on the larger tract for twice as long as for the smaller tract.
d. The above examples are over-simplified for most situations, but are intended to give a general idea of how rotation of water use operates.
037-1 Wyo. Code R. § 1-9