(1) District boards are financed by appropriations from the general funds of each county in the district in proportion to the population in each county.
(2) First- and second-class cities which elect to be included in the district contribute to the county in which they are located in the way provided for city-county boards under 50-2-111.
(3) All funds shall be deposited with the county treasurer of one of the counties as agreed upon by the commissioners of the counties in the district. The county treasurer shall disburse the funds as county funds.