Ala. Code § 11-50-12
All cities and towns which own and operate an electric light plant or system or any power plant of any kind may combine such electric light and power plants and system with the waterworks or waterworks system owned and operated by the city or town, and the receipts and revenues derived from the electric light plant and works or from such power plant may be applied in payment of or pledged to secure the payment of any indebtedness incurred by the city or town in the construction, maintenance, or extension of its waterworks system or any additions or improvements thereto; and any electric or hydroelectric power or power plant of similar kind owned and operated by any of the cities and towns within the provisions of this section may use such lighting or power plants and systems for the operation of its waterworks system and plant.
Ala. Code § 11-50-12 (1975)