Lake Forrest Dam Repair

Lake Forrest Dam Project

The Lake Forrest Dam is classified by the Georgia Environmental Protection Division (EPD) Safe Dams Program as a Category I High Hazard Dam.

In 2009, inspections identified several deficiencies affecting the dam’s structural integrity.

To address safety concerns, the cities of Atlanta and Sandy Springs entered into an intergovernmental agreement to jointly fund and implement repairs, improvements, and long-term solutions necessary to bring the dam into compliance with applicable regulations.

The cities continue to monitor the dam regularly for safety and structural integrity.

Lake Forrest Dam is located beneath Lake Forrest Drive along the Atlanta–Sandy Springs border.

Two smaller privately owned dams located upstream directly affect the integrity and operation of the larger Lake Forrest Dam.

Project Timeline and Updates

September 2022

Interim repairs were completed and disturbed areas were stabilized. Two remaining tasks included:

• Installation of a conduit for power cable connections
• Completion of a limited as-built survey documenting completed improvements

Once finalized, the as-built survey documentation was scheduled to be submitted to the Georgia EPD Safe Dams Program.

The interim repairs were designed to provide temporary improvements to the embankment and spillway conduit while maintaining the lake at a reduced water level until long-term repairs can be implemented.

The work was intended to improve dam safety and support compliance with the Georgia Safe Dams Act of 1978.

Temporary repair measures included:

• Clearing and grubbing of the work area
• Installation of erosion control measures
• Grouting near the 24-inch corrugated metal spillway conduit
• Partial lining of the existing principal spillway conduit
• Fish relocation activities
• Removal and replacement of the auxiliary overflow conduit
• Dredging and removal of silt and sediment
• Installation of a filter ring and electric pump to maintain reduced lake levels
• CCTV inspection of infrastructure components
• Stabilization of disturbed areas using vegetation

March 2022

• Completed clearing and access improvements to the lakebed
• Completed embankment grouting and spillway lining work
• Replaced the overflow conduit and stabilized the embankment
• Maintained reduced lake levels using a diesel pump
• Submitted modified filter-ring design plans to Georgia EPD for review and approval
• Coordinated with Georgia Power regarding electrical service for a planned electric pump

August 2021

• Georgia EPD Final Consent Order (PDF)
• The cities of Sandy Springs and Atlanta jointly advanced interim repair construction, including pipe lining, grouting, and pumping operations to maintain lower lake levels.
• Repair measures were coordinated with the Georgia EPD Safe Dams Program.

October 2019

• Lake Forrest Dam project update issued on October 1, 2019

September 2019

• Georgia EPD proposed a draft consent agreement for negotiation

August 2019

• Plans and specifications for temporary repair measures were completed
• The City of Atlanta received a Notice of Violation and draft consent agreement from Georgia EPD

March 2019

• Mandatory biennial dam inspection completed
• Engineering recommendations identified the need for temporary repair measures

January 2019

• Dam breach and sensitivity analysis studies were completed

June 2018

• Independent contractors completed a cost validation study

April 2018

• A third-party consulting firm completed a peer review of the alternative analysis report

December 2017

• An Interim Emergency Action Plan was prepared