A. After the hearing required by Section 901.42 of this title, and at least seven (7) days prior to the beginning of the budget year, the board shall adopt the budget. The board may add or increase items or delete or decrease items in the budget. In all cases the proposed expenditures shall not exceed the estimated revenues for any fund.

B. The adopted budget shall be filed with the county clerk of each county in which the district is located on or before the first day of the budget year. At the same time that the budget is filed with the county clerk, one copy of the budget as adopted shall be transmitted to the State Auditor and Inspector and one copy shall be kept on file in the office of the district.

C. The adopted budget shall be in effect on and after the first day of the fiscal year to which it applies. The budget as adopted and filed with the State Auditor and Inspector shall constitute an appropriation for each fund, and the appropriation thus made shall not be used for any other purpose except as provided by law.