Okla. Stat. tit. 82, § 82-105.15: Time for commencement of works

A. Any permit shall expire unless the applicant begins

construction of the works within two (2) years of the issuance of

the permit by the Board. The Board may, as necessary and deemed

appropriate under the circumstances, extend the time for the

beginning of construction beyond the time allowed in the permit for

good cause shown, such as engineering difficulty or other valid

reason over which the applicant has no control.

B. If the Board does not receive a written notice of

commencement of works or request to extend time within thirty (30)

days after the end of the two-year period, the permit shall be

deemed expired after written notice to the applicant.

C. Provided, nothing in this section shall be construed as

extending the time within which the waters authorized for use must

be placed to actual beneficial use as provided in the permit and

Sections 105.16 through 105.18 of this title.