Wyo. Stat. Ann. § 41-9-259

All drainage assessments shall be collected by the same officer and in the same manner and at the same time as state and county taxes are collected and when collected shall be paid to the treasurer of the district, except such assessments, together with interest, penalty and costs thereon, as are collected upon assessments levied for the payment of principal and interest of bonded indebtedness of said district, which funds shall be retained by the county treasurer of the county in which such district is organized, and the principal and interest of all bonded indebtedness of such district shall be paid by such county treasurer from such fund, at the place of payment designated in said bonds and interest coupons; provided, that when all bonded indebtedness of any drainage district is fully paid and retired such funds remaining in the hands of the county treasurer shall be paid to the treasurer of such district, for the use of the district. The commissioners of any drainage district may elect the treasurer of the county having jurisdiction of such district treasurer of such district. Division 4. Construction of Works 41-9-260. Bidding procedure when cost over $500.00. In all cases where the work to be done at any one time under the direction of the commissioners shall, in their opinion, cost to exceed five hundred dollars ($500.00), the same shall be let to the lowest responsible bidder, and the commissioner shall advertise for sealed bids, by notice published in some newspaper published in the county in which the petition is filed, and may advertise in one (1) or more newspapers published elsewhere. If there be no newspaper published in the county in which the petition is filed, they shall advertise in some newspaper published in an adjoining county, which said notice shall particularly set forth the time and place when and where the bids advertised will be opened, the kind of work to be let and the terms of payment. Said commissioners may continue the letting from time to time, if in their judgment the same shall be necessary, and shall reserve the right to reject any and all bids.