The managers are responsible for maintaining the projects of the watershed district in a condition so that they will accomplish the purposes for which they were constructed.
(a) The cost of normal or routine maintenance of the projects of the watershed district, and the cost of removing obstructions and accumulations of foreign substances from a drainage system, shall be paid from the maintenance fund on the order of the managers.
(b) The managers may assess all the parcels of property and municipal corporations previously assessed for benefits in proceedings for the construction or implementation of the project, to establish a maintenance fund for the project. The assessment must be made pro rata according to benefits determined. An assessment for the benefit of the maintenance fund may not be made when the fund exceeds 20 percent of the original cost of construction or implementation of the project. The auditors of the affected counties shall file a tabular lien statement covering the assessment in the office of the county recorder for the county when the assessment order from the managers is received.
(c) The assessment shall be collected as provided in the order in the same manner as provided in section 103E.731.
(d) Before ordering the levy of an assessment for the benefit of the maintenance fund, the managers may give notice of a hearing on making the assessment and establishing the maintenance fund.