If there is a deficiency in the funds collected from special assessments by reason of the inadequacy of the method of collection adopted by the district under section 48-946, the district shall make good the deficiency, reimbursing itself from the funds collected from the installments when they are received. If the method as prescribed by section 48-946 has not been adopted, the district may, but is not obligated to, make good a deficiency by a temporary loan out of some other fund.