(a) Authorization by commissioner. Any commissioner is authorized to issue a letter authorizing the diversion of water from unsponsored or storage-limited projects for domestic and livestock use.(b) Revocation of authorization. When compliance with the conditions contained in the letter authorizing the diversion of water is not occurring or, in the case of domestic use, water becomes reasonably available through a water supply system, the authorization may be revoked by sending a letter of revocation to the user setting forth the basis for the revocation and signed by a commissioner.