Okla. Stat. tit. 69, § 69-601: Authority and duties of county commissioners

A. The county highway system shall be composed of all public

roads within any county, less any part of any road or roads which

may be designated as a state highway by the State Transportation

Commission. It shall be the duty of the board of county

commissioners in each county to construct and maintain as county

highways those roads which best serve the most people of the county.

For this purpose the board of county commissioners is authorized to

use any funds which are in the county highway fund, subject to

statutory restrictions on the use of any of such funds, together

with any money or item of value derived from any agreement entered

into between the county and the Transportation Commission, the

federal government, this state, any other county or political

subdivision of this state or other governmental entity, or any

citizen or group of citizens who have made donations for that

purpose. The boards of county commissioners of the various counties

shall have exclusive jurisdiction over the designation, construction

and maintenance and repair of all of the county highways and bridges

therein. All interlocal cooperation agreements made pursuant to

this section between counties and those political subdivisions or

citizens of a county shall be submitted to the district attorney of

each of the counties subject to the agreement for approval. All

other interlocal cooperation agreements shall be submitted and

approved in accordance with Sections 1001 through 1008 of Title 74

of the Oklahoma Statutes.

B. The boards of county commissioners are hereby authorized to

establish road improvement districts as provided by law for existing

roads in the unincorporated areas of counties. The boards of county

commissioners may also have improvements made on existing roads in

unincorporated areas of counties on a force account basis.