Lake Forrest Dam Repair

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The Lake Forrest Dam is classified by the State Safe Dams Program of the Environmental Protection Division of the Georgia Department of Natural Resources (EPD) as a Category I, High Hazard dam.  In 2009, the dam was identified with several deficiencies impacting its structural integrity.  With safety a primary concern, the cities of Atlanta and Sandy Springs, through an Intergovernmental Agreement, have agreed to share jointly in addressing and implementing improvements, repairs and/or alterations or other long-term options to bring the dam into compliance with regulations. The cities monitor the dam regularly for safety and structural integrity.   

Lake Forrest Dam runs beneath Lake Forrest Drive on the Atlanta-Sandy Springs border.  Two smaller, private, dams are located upstream and have a direct impact on the integrity of the Lake Forrest Dam (the larger dam). Below is a chronological order of activity related to efforts to repair the Dam: 

Project Update 

June 21, 2017

Property owners were formally notified that the middle dam, which is private property and located upstream of the larger dam, needs correction prior to repairs of the larger dam. 

April 11, 2017

Dam property owners and representatives from the cities of Atlanta and Sandy Springs meet with State Safe Dams office to provide an update. Safe Dams provided an extension on the deadline to submit a permit application and plans to address the issue with the larger dam.  Dam owners are required to submit an Emergency Action Plan (EAP) to address action steps should the dam fail, with the EAP due by September 1, 2017. 

February 16, 2017

Surveyors will be on-site collecting additional data on February 16th, 17th and 20th.

November 30, 2016

Survey required to evaluate the alternatives to address issues with the dam is scheduled to start the first week in December and will take until at least the end of the month to complete. Inclement weather and other issues may extend survey activities into January. 

Sept. 8, 2016

Boring work, as part of geotechnical testing, is complete. Lake Forrest Drive is back open for motorists.

August 24, 2016

Lake Forrest Dam/Lake Forrest Drive:  Boring work, as part of geotechnical testing, will begin on Monday, August 29, weather permitting. underway at the Lake Forrest Dam.  Lane closures will be in place 9 a.m. – 9 p.m. while the testing is underway between Forrest Lake Dr and Barbara Lane.

August 9, 2016

The fence installation is complete.  The design consultant is scheduling the drill rig to complete soil borings.  We anticipate this work starting in the next few weeks. 

July 19, 2016 - Modifications to the existing riser are complete.  The fence near the right-of-way is scheduled to be installed within the next couple of weeks.  Based on recommendations from the ecologist, there will not be any additional fish relocations at this time.  Next steps include soils testing and collecting additional survey information.

April 20, 2016 - The drawdown of water from the lake has been completed.  The contractor is in the process of completing the modifications to the existing riser required to accommodate the lower lake elevation. Once that work is completed, coordination of relocation of the remaining fish will begin. Following, we will collect additional survey and soils information to complete an analysis of the issues related to the dam. That analysis will be presented to both City Councils. 

January 27, 2016 -  The final phase to drain the main lake is expected to begin on February 1st, weather permitting.  Following the excavation around the existing riser, the lake will be lowered approximately 1-2’ per week, a similar lowering rate to previous draining’s.  We expect to lower the lake an additional six feet, with approximately 4’ of water remaining. 

Once the lake is at 4’, the remaining fish will be removed. The initial process uses nets dragged across the water, with manual pick up of any fish which may be remaining. 

Our plan is to keep the lake at the 4’ level, with inflow from the upstream lake, until the issues with the dam are addressed.  We are in the process of reviewing alternatives provided by the design engineer.   

December 15, 2015 -  The next step in repairing the Lake Forrest Dam will be removing another six feet of water from the primary lake adjacent to the Dam and then removing any remaining fish. Those steps are expected to begin at the beginning of 2016, with the update provided as part of a status report presented to the Sandy Springs City Council during its regularly scheduled meeting Tuesday night.  Once the lake has been drained and allowed to dry, additional geotechnical testing will be conducted to help with determination of best options for repair.  The City Council has requested staff to look at multiple options. Once a repair option is selected and approved, it could take one to two years for designs to be finalized and permitted allowing for construction to begin.

August 31, 2015 - The first phase of fish removal is complete. The lake needs to achieve a level of dryness for soil analysis to be completed. Following those results, the design will be completed and finalized.

July 17, 2015 -  The City of Sandy Springs has completed the first phase of draining the lake.  The lake has been lowered approximately six feet from the original elevation. 

Relocation of some of the fish in the lake to a private pond in accordance with applicable regulations is currently scheduled for the week of July 20, 2015.  The first step will be tree removal at the interior face of the dam in order to get the boat into the water. 

Fish relocation generally occurs when there is three feet of depth in a water body.  Since the lake is currently still too deep to net all of the fish, a second relocation will likely occur when there is approximately four feet of water remaining in the lake. 

Final plans have been submitted to the Georgia Safe Dams Program relating to the lowering of the water level in the lake.  As part of the second phase of lowering the lake that will occur shortly after the first effort of fish relocation, this lowering will result in the lake being maintained at a depth of approximately four feet until a repair method is completed that will resolve all the safety issues with the dam. 

All work will be completed in accordance with U.S. Army Corps of Engineers Nationwide Permit 03, Georgia Rule for Dam Safety and the Manual for Erosion and Sediment Control in Georgia. 

With the lowering of the lake level to approximately four feet in depth, an analysis of the lake and dam condition will occur next that will provide information to help with design repair considerations. This timeline may take a while since the newly exposed lake areas have to dry out. 

June 16, 2015 - During its June 16 meeting, the Sandy Springs City Council approved in basic form, an Intergovernmental Agreement with the City of Atlanta regarding repairs of the Lake Forrest Dam.  As part of the Agreement, the two cities shall share jointly in addressing and implementing improvements, repairs and/or alterations or other long-term options to bring the am into compliance with the Safe Dams Act, including associated costs. 

The project will be divided into two phases. Phase One consists of lowering the level of the large lake connected to the dam to eliminate any immediate risks to the impact area due to a potential dam failure and to enable necessary testing and technical evaluation. A project plan for Phase Two will be developed once the Lake is drained and engineers are able to best evaluate and develop suggested repairs with those recommendations presented and approved by both cities.

May 21, 2015 - The City of Sandy Springs began a phased siphoning of water from the primary lake serviced by Lake Forrest Dam. The project intended to reduce the lake up to 50 percent of capacity.

February 11, 2015 - A meeting with property owners surrounding the three lakes was held to overview the needs for the dam repairs. Project Background and  Information: Lake Forrest Dam Project Update Presentation 


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