Intrenchment Creek treatment plant (Key Road)

The record

The city's capital-projects page says the plant was built in 1910 and upgraded in 1936, and treated the northern half of the South River sewer service area, including a small part of DeKalb; because it could no longer meet modern effluent limits, its flows are being moved to the South River plant. That page gives a scheduled completion date of October 22, 2024, but still lists the project as active, and in March 2025 a City Council committee extended the contract to September 19, 2025; this research found no confirmation that decommissioning is finished. The city's system overview says three plants were running by 1915 (Intrenchment Creek, Peachtree Creek and Proctor Creek), while the South River Watershed Alliance dates the first treatment plant to 1917, so early dates vary. William Cobb's grist mill, where Hardee's corps halted at dawn on July 22, 1864, to get guides, stood on the east side of Intrenchment Creek just above the Key Road bridge, by the plant entrance (GHS marker, 1510 Key Rd).

Today: Treatment plant grounds on Key Road SE. The city has been decommissioning the plant; its contract was extended to September 2025.