The commissioner and the board shall encourage and support regional water planning whenever possible. In the future, if there is a specific appropriation of state or federal funds for regional water supply planning, the board may require regional water supply planning and may provide incentives to encourage such regional planning, using the rulemaking authority under this part for so long as such specific appropriation is in effect. Among other criteria, state agencies are authorized to consider regional planning and regionalization efforts when awarding grants, making loans or funding projects.
T.C.A. § 69-7-308