The Board of Supervisors shall establish and provide for a capital reserve fund or funds as it determines appropriate to pay for improvements or repairs to and replacement of District buildings, equipment, and other capital assets of the District. When so established, a capital reserve fund or funds shall be kept intact and separate from other monies of the District, and shall be accounted for as a pledged asset for the purpose for which the fund was established. The cost of contributions to such capital reserve fund or funds shall be included in the annual budget of the District.