A private group agreed this week to spend the money necessary to complete a water management plan for the Apalachicola-Chattahoochee-Flint river basin, which includes Lake Lanier. The ACF Stakeholders’ 56-member governing board, meeting earlier this week in Eufaula, Ala., directed its technical contractors — Black & Veatch, Atkins Global and the Georgia Water Resources Institute at Georgia Tech — to finish its work this summer with the goal of wrapping up the Sustainable Water Management Plan by late fall. Crafting the plan has been the organization’s goal since its creation nearly five years ago.