Okla. Stat. tit. 19 § 869.4
The jurisdictional area of a lake area planning commission may include all or part of the unincorporated area of any county or counties authorized to create such a planning commission, provided that the jurisdictional area shall be limited to a three-mile perimeter from the normal shoreline elevation of the upstream terminal port or turnaround where navigation ends, or any reservoir or reservoirs constructed by the Bureau of Reclamation, the U.S. Army Corps of Engineers or the Grand River Dam Authority, regardless of the population of the county or counties or the cities or towns therein. In the event that the three-mile perimeter described above includes portions of two or more counties, the counties may cooperate in a joint lake area planning commission; provided, that no lake area planning commission may establish or maintain any jurisdictional area within any county or counties without a resolution of participation from the board of county commissioners of the county or counties.
In the event that all or part of an incorporated city or town lies within the three-mile perimeter, as described above, the incorporated areas may elect to come under the jurisdiction of the lake area planning commission. In the event that an incorporated area elects to come within the jurisdiction of a lake area planning commission, the commission shall become the planning commission or zoning commission, or both, for the incorporated area or areas in their entirety, without regard for the three-mile perimeter from the normal shoreline elevation.
In counties where a metropolitan area planning commission exists, the board of county commissioners may utilize that commission in forming a lake area planning commission.
In no event shall the boundaries of any statutorily authorized planning commissions overlap, and where a situation of overlap does occur, the jurisdictional question shall be settled on the basis of prior jurisdiction.
Okla. Stat. tit. 19, § 869.4