Okla. Stat. tit. 82, § 82-1613: Existing prior use may continue - Conditions

Any use that exists prior to May 13, 1980, which does not meet

the minimum standards specified and authorized by the Oklahoma

Floodplain Management Act may continue. However, unless brought

into compliance with the minimum standards set forth in regulations

adopted pursuant to the Oklahoma Floodplain Management Act such uses

may not be substantially altered, enlarged or added to.