It is the intent of the Legislature in enacting Sections 19608.5, 19608.6, and 19608.8 to provide the revenues necessary for the financing by joint powers agencies of the described facilities and projects which shall be deemed to be public capital improvements within the meaning of Article 4 (commencing with Section 6584) of Chapter 5 of Division 7 of Title 1 of the Government Code. Deposits into the account in the fund in accordance with paragraph (1) of subdivision (a) of Section 19606.1 shall continue through and including either the 20th year after the initial calendar year in which the revenues are collected, or whatever period of time is necessary to repay any borrowings of joint powers funding mechanism, including, but not limited to, retirement of bonded indebtedness, loan repayments, and monthly payments involving lease-purchase programs made by a joint powers agency to finance described facilities and projects, whichever time is longer.