In July of each year, the board of directors shall estimate and itemize all the expenses and obligations of the district, including expenses of directors, expenses of operating the office, debt service and retirement, and obligations and liabilities to the United States for which provision must be made. The board of directors may include in such budget funds deemed necessary to create reserve funds to meet future payments under district contracts. Upon the completion and adoption of such budget, the board of directors shall make a tax levy in an amount sufficient to meet such budget. Such levy shall be in the form of a resolution, adopted by a majority vote of the members of the board of directors of the district. Such resolution shall levy in mills, but not exceeding one mill, sufficient to meet all the expenses, obligations, and liabilities of the district as provided in the budget.