A.R.S. § 48-2051: Payment of costs by sanitary district

A. The board may order in the resolution of intention that all or part of the cost of any work shall be paid from the treasury of the sanitary district from the fund it designates when so ordered. The board, in making up the assessment, shall first deduct from the whole cost such part as has been ordered paid from the treasury or other source of monies and assess the remainder of the costs and expenses proportionately, according to the benefits received, on the lots to be assessed for the work.

B. If all of the cost is to be paid out of the treasury, no assessment may be made and the whole amount is payable thirty days after the acceptance of the work by the sanitary district.