Okla. Stat. tit. 19, § 19-1210: Proportionate payment of costs

A. Each county in which any of the area of a district is

located shall pay its proportionate share of the cost of the

district, based on the ratio which that part of the population of

such district residing in the county bears to the total population

of the district. Such cost shall be paid from the county treasury,

but shall not exceed the equivalent of one (1) mill on each dollar

of valuation in the district.

B. Any incorporated town or city that is a party to the

district shall pay a proportionate share of the cost of the

district, based on the ratio which that part of the population of

such district residing in the town or city, bears to the total

population of the district.

C. Such cost shall include so much of the following as is not

paid from revenues of the district:

1. All operating and maintenance expenses necessary or

desirable for the prudent conduct of affairs of the district and the

principal of and interest on the obligations issued or assumed by

the district in the performance of the purposes for which it was

organized; and

2. Adequate reserves for the retirement of indebtedness,

maintenance and other purposes necessary and expedient to meeting

all obligations of the district.

D. Any revenue received by the district shall be devoted,

first, to the payment of operating and maintenance expenses and the

principal and interest on outstanding obligations and, thereafter,

to such reserves for improvements, retirement of indebtedness, new

construction, depreciation and contingencies as the board of

directors may from time to time prescribe.