DeKalb water and wastewater CIP: clear wells, generator quote of $18M and multi‑phased Snapfinger expansion

DeKalb County’s Public Works & Infrastructure committee received a multi-part update on drinking-water and wastewater capital plans that included redundancy work at the Scott Candler water treatment plant, equipment upgrades at the Polebridge wastewater plant, and staged expansion at the Snapfinger wastewater facility aimed at consent-decree deadlines.

"DeKalb County is unique in the metro area in that we have one water supply and we have one water treatment plant," Director Hower told commissioners as he introduced the drinking‑water segment. Assistant director Dora Taborta, who spoke to the plant projects, said the county intakes water from the Chattahoochee River and is pursuing projects to reduce single points of failure.

Key projects described:

- Scott Candler clear wells and transfer-pump upgrades: Staff propose eliminating the existing single transfer path by constructing two clear‑well storage tanks and adding a secondary pump station to create a redundant flow path to distribution; planned filter media replacement was described as a compliance-driven measure to maintain performance amid tightening federal standards.

- Chemical handling and operator safety: Taborta said the county is converting from caustic to liquid lime dosing to improve operator safety and stabilize pH for corrosion control.

- Backup power: Kenneet Gobin, assistant director of plant operations, said the committee is collecting quotes for generators and process-control upgrades. "The generator project cost we have gotten at a $18 million quote at the moment," he said, and noted lead times for large generators are being driven by regional demand from data centers.

- Polebridge wastewater plant: Staff reported that the electrical switchgear is at end of life, with an estimated cost cited near $5 million and a roughly one‑year lead time for procurement; related bus-duct and gate replacements were described as multi-year efforts needed to support future UV disinfection and other improvements.

- Snapfinger expansion (phased approach): Katherine of ACOM reviewed Phase 3A–3E sequencing to raise hydraulic capacity and remove gaseous chlorine through UV equipment. She described Phase 3A (in bid) to increase influent pumping capacity (to 160 MGD pump station), add equalization capacity and to put the plant on track for 100–54 MGD treatment and eventual full buildout. A future Phase 4 study of sludge‑treatment options (thermal hydrolysis and digestion) was noted; Katherine said a July 2024 design study estimated that work at about $414 million.

Commissioners asked how the county’s Southface clean-energy study and an imminent solar RFP might intersect with resiliency plans. Staff said solar or floating-solar could provide partial daytime power and storage support, but that high-service pumps operate at 4,160 volts and require substantial capacity; a hybrid approach with solar and batteries could reduce operating costs but would not replace emergency generators.

Staff said they will continue to refine project scopes, pursue procurement approaches (piggybacking on state contracts where possible) and return with procurement timelines and more granular cost estimates.