Wyo. Stat. § 41-3-771
To levy and collect taxes under class A as provided in W.S. 41-3-770, the board shall, in each year, determine the amount of money necessary to be raised by taxation, taking into consideration other sources of revenue of the district, and shall fix a rate of levy which when levied upon every dollar of assessed valuation of property within the district, and with other revenues will raise the amount required by the district, to supply funds for paying expenses of organization, for surveys and plans, paying the costs of construction, operating and maintaining the works of the district; provided, however, that said rate shall not exceed one-half (1/2) mill on the dollar, prior to the delivery of water from the works, and thereafter not to exceed one (1) mill on the dollar, of assessed valuation of the property within the district, except in the event of accruing defaults and/or deficiencies where an additional levy may be made as provided in W.S. 41-3-775. The board shall on or before the third Monday of July of each year, certify to the board of county commissioners of each county within the district or having a portion of its territory in the district, the rate so fixed with direction that at the time and in the manner required by law for levying of taxes for county purposes, such board of county commissioners shall levy such tax upon the assessed valuation of all property within the district, in addition to such other taxes as may be levied by such board of county commissioners, at the rate so fixed and determined; provided, however, that said assessment and tax levied under the provisions of this act shall not be construed as being a part of the general county mill levy.
W.S. 41-3-771