Neb. Rev. Stat. §§ 46-644
Permits granted by the Director of Natural Resources shall be valid for a period of five years after the granting of a permit and as long thereafter as the water for which the permit is granted is used. For the purposes of the Municipal and Rural Domestic Ground Water Transfers Permit Act, the commencement of construction of facilities to provide water for beneficial use shall be deemed the date of the commencement of beneficial use. If it appears that the holder of a permit granted under the act has not used water for a beneficial purpose and in accordance with the terms of the permit for more than five years, such permit may be revoked or modified by the director. The procedure for such revocation or modification shall be the same as that provided for in sections 46-229.02 to 46-229.05.
Neb. Rev. Stat. §§ 46-644