1. Pay the current expenses of operating and maintaining the sewerage, drainage and treatment system of the district;

2. Pay the principal of and premium if any and interest on all bonds and notes issued by the district as they become due and payable;

3. Create and maintain such reserves as may be required by the trustees or any trust agreement or resolution securing bonds and notes;

4. Provide funds for paying the cost of all necessary repairs, replacements and renewals of the sewerage, drainage and treatment systems of the district;

5. Payment of obligations. Pay or provide for any amounts that the district may be obligated to pay or provide for by law or contract, including any resolution or contract with or for the benefit of the holders of its bonds and notes; and

6. Provide revenue in order to pay all or part of the present or projected cost to improve, enlarge or expand the district's system, including payment of interest accruing on any indebtedness for such purposes.

Sec. 18. Assessments. When the district formed under this Act has constructed and completed a common sewer, the trustees may, in order to defray a portion of the expense of the construction of a sewer, determine what lots or parcels of land are benefited by the sewer and estimate and assess upon the lots and parcels of land, and against the owners of the lots and parcels of land, or person in possession or against whom taxes are assessed, whether the person to whom the assessment is made is the owner, tenant, lessee or agent and whether the same is occupied or not, a sum not exceeding the benefit as the trustees may determine just and equitable towards defraying the expense of constructing and completing the sewer, together with such sewage disposal units and appurtenances as may be necessary. The assessments may not exceed the cost of the sewer and sewage disposal units. The trustees shall file with the clerk of the district the location of the sewer and sewage disposal unit, with a profile description of the same, a statement of the amount assessed upon each lot or parcel of land so assessed, a description of each lot or parcel and the name of the owner of the lots or parcels of land or person against whom the assessment