Ala. Code § 45-17A-83.08

No expenditures for any new construction, additions, or replacements to any public utility system or equipment shall be made by the board where the total cost will be more than fifty thousand dollars ($50,000), without the consent and approval of the city council. The city council, if requested by the board, may increase the fifty thousand dollar ($50,000) limitation set forth herein by ordinance duly adopted. This section shall not be deemed to apply to purchases of gas inventory.