1. To maintain and preserve the ditches, drains, levees or other improvements made pursuant to sections 242.010 to 242.690 and to strengthen, repair and restore the same, when needed, and for the purpose of defraying the current expenses of the district, the board of supervisors may, upon the completion of such improvements and on or before the first day of September in each year thereafter, levy a tax upon each tract or parcel of land and upon corporate property within the district to be known as a “maintenance tax”. The maintenance tax shall be apportioned upon the basis of the net assessments of benefits accruing for original construction or subsequently adjusted reassessments, shall not exceed twenty percent thereof in any one year and shall be certified to the collector of the revenue of each county in which lands of the district are situated in the same book in like manner and at the same time as the annual installment tax is certified, but in a separate column, under the heading “maintenance tax”.

2. The collector shall demand and collect the maintenance tax and make return thereof and shall receive the same compensation therefor and be liable for the same penalties for failure or neglect so to do as is provided in this section for the annual installment tax, except that after all annual installments of the total tax have become due, and thereafter it is only desired and necessary to levy and collect such maintenance tax, the board of supervisors of such drainage districts may, by resolution, provide that in the tax books containing the maintenance tax, it shall be sufficient if the several governmental lots, forty-acre tracts or other subdivisions of land as they appear in the decree of the circuit court organizing the district, be conveniently combined and described together, if contiguous, according to each ownership, and the names of the owners thereof as they may appear in the deed records, may be used in such tax book, and the certificate thereof, as provided by section 242.460 may conform thereto. The amount of the maintenance tax levied against such combined tracts shall be the same as the aggregate of the tax if levied against each separate tract and errors in the combined descriptions of such lands or in the names of the owners thereof, or in the amount of such maintenance tax as they appear in such book, shall not affect the validity of such tax or the lien thereof, and any such errors may at any time be corrected by resolution of the board of supervisors of such drainage district.