(a)      For the purpose of retiring the bonds and notes authorized to be issued by this subtitle and the payment of the interest thereon, there shall be levied against all the assessable property within such sanitary district, by the County Councils of Montgomery and Prince George's counties, respectively, annually so long as any of such bonds or notes are outstanding and not paid, a tax sufficient to meet the interest on such bonds and notes as it becomes due, and to pay the principal thereof as they mature, such tax to be determined, levied, collected and paid over in the following manner: At least 30 days before the tax levying period of each year, the respective county executives shall certify to the WSSC the whole valuation of assessable property within the sanitary district. Such WSSC shall then determine the amount necessary to be raised for the ensuing year for the payment of interest on all outstanding bonds and notes, the principal of all serial bonds and of all notes maturing in such year and the proportionate part of principal of all outstanding sinking fund bonds, the amount to be paid on the principal of such sinking fund bonds in any 1 year to be determined by the usual table of redemption of bonds by annual deposit in a sinking fund on interest; and after deducting all amounts in hand applicable to payment of interest and principal on such bonds and notes, as hereinafter provided, it shall determine the number of cents per $100 necessary to raise such amount and shall so certify to both the County Councils of Montgomery and Prince George's counties. The County Councils of Montgomery and Prince George's counties in their next annual levy shall levy such tax on all land and improvements and any other property assessed for county tax purposes within such sanitary district, which tax shall be levied and collected as county taxes now are or may be hereafter by law levied and collected, and have the same priority rights, bear the same interest and penalties and in every respect be treated the same as county taxes. The tax so levied for the ensuing year shall be collected by the respective tax collecting authorities, and every 60 days they shall remit the whole amount of tax collected to such WSSC. From the money so received, together with the amount in hand to the credit of such current bond fund, or applicable to the payment of interest on its bonds and notes and the principal thereof, the WSSC shall first pay all interest on such bonds and notes as it matures, pay, or reserve a sufficient amount of money to pay, its serial bonds maturing in such taxable year, and shall then deposit in some bank or banks in 1 or both of the counties, to the credit of both counties and the WSSC, as a joint fund to be known as "sinking fund account", the amount so raised for the payment of the proportionate part of the principal of such sinking fund bonds.

      (b)      The WSSC and the respective counties shall, from time to time, invest the sinking fund in any bond or bonds in which savings or trust funds are authorized to be invested by national banks by the U.S. Treasury Department. Should receipts from the tax or other sources be inadequate to pay the principal of the serial bonds maturing in the taxable year and to deposit the principal payment on the sinking fund bonds, by reason of defaults or otherwise, such deficiency shall be added to and collected in the next year's tax. The WSSC is authorized to pay the interest on any bonds it may issue prior to the first tax levying period out of the proceeds of the sale of the bonds. For the purpose of paying the principal and/or interest of bonds due or to become due within 4 months and for paying the interest maturing on any bonds within 4 months and not otherwise adequately provided for, or for meeting payments required to be made to its employees and laborers and not otherwise provided for, the WSSC may borrow money in anticipation of taxes, sale of bonds or other revenue of the fiscal year in which the loan is made or in anticipation of the taxes, sale of bonds or other revenue of the next succeeding fiscal year, and such loan shall be payable not later than the end of the fiscal year next succeeding the year in which the loan was made. Negotiable notes shall be issued for all money so borrowed, which notes may be renewed from time to time, and money may be borrowed upon new notes from time to time for the payment of any indebtedness evidenced thereby; but all such notes and loans shall mature within the time limited for the payment of the original loan. Such notes may be disposed of in such manner as the WSSC may determine, provided, however, that there shall never be outstanding at any 1 time any such notes in an aggregate amount in excess of an amount equal to the total principal of and interest on bonds of the sanitary district provided to be due and payable in the fiscal year in which such notes are issued. All such notes shall be authorized by resolution of the WSSC, which shall fix the actual or maximum face amount of the notes, the actual or maximum rate of interest to be paid upon the amount borrowed and the actual or approximate maturity of the notes. The form and manner of execution of such notes shall be determined by the WSSC.

      (c)      In order that the prompt payment of interest and the proper provision for the payment of the principal of the bonds and notes shall be assured, the prompt and proper performance of the respective acts and duties heretofore defined is specially enjoined, and a person may not fail to perform the necessary acts and duties hereafter set forth, to pay over the funds as required, or to use the funds or any part thereof for any other purpose than for the payment of the principal and interest on the bonds and notes.