Lake Peachtree Spillway Replacement

Project Schedule

 Path Detour Map (During Spillway Construction (PDF)

  • Phase 1 – Schematic Design (Apr – Aug 2016) - COMPLETE
  • Phase 2 – Public Meetings (Aug 2016 – Sep 2016) - COMPLETE
  • Phase 3 – Preliminary Design (Sep 2016 – Dec 2016) - COMPLETE
  • Phase 4 – Design Development (Dec 2016 – Apr 2017) - COMPLETE
  • Phase 5 – Final Design (Apr 2017 – Jun 2017) - COMPLETE
  • Phase 6 – Contract Documents (Jun 2017 – Jul 2017) - COMPLETE
  • Phase 7 – Bidding (Jul 2017 – Aug 2017) - COMPLETE - contract awarded 8/17/2017

Phase 8 – Construction (Aug 2017 – May 2018) - See the Lake Water Level Impacts (PDF) for lowering the lake by 8 feet and 6 feet (Stages 1 and 3)  

  • Stage 1 - (Began Monday, August 28) Lower Lake Peachtree 8 ft. (+/- 3 weeks) - COMPLETE
  • Stage 2 - (September - October) Construct Coffer Dam (+/- 4 weeks) - COMPLETE
  • Stage 3 - (November) Lower Lake Kedron 2 ft., Raise Lake Peachtree 2 ft.  - COMPLETE  
  • Stage 4 - (December - February) Construct New Spillway Foundation - COMPLETE
  • Stage 5 - (APRIL) POSSIBLY raise Lake Peachtree 2 ft. - COMPLETE
  • Stage 6 - ( March - May) Construct New Spillway Walls & Weirs - COMPLETE
  • Stage 7 - Return Lakes Peachtree & Kedron to Full Pool - UNDERWAY

August 16, 2018 Update - Lake Peachtree Is Refilling

At the August 16 City Council meeting, City Manager Jon Rorie announced that Lake Peachtree has begun to refill. Full pool is 784.5', and the lake was at 776.4' as of that day, meaning about eight feet to go. For reference, it takes about one inch of rainfall to fill the lake by one foot, and a small amount of water must always be released to maintain Flat Creek below the lake. September's average rainfall is usually between four and five inches. Separately, the contractor still has work to do as the lake fills, including final closeout of the old outflow pipe under the dam and outflow area, path connections to the new bridge, and landscaping.

May 17, 2018 Update - Still 4 Weeks Behind Original Schedule due to weather

View 5/17/18 Presentation (PDF)

Dan Davis of ISE gave an update on the Lake Peachtree Spillway Construction – the project is still about 4 weeks behind schedule due to weather, but is being brought up by two more feet, which should give visible if shallow water in most of the lake bed. The lake would remain at this level through July 4, and would be re-lowered beginning July 5 for the final removal of the coffer dam, which should not take more than two weeks to complete. The new path bridge at the spillway was scheduled to be set in place on July 15. City Manager Jon Rorie reported that, once the lake was refilled, the City would ask the DNR to do another assessment of the fish population to see if any restocking would be necessary.

March 15, 2018 Update: 3-4 W eeks Behind Schedule, Working To Regain Time

View 3/15/18 Presentation (PDF)

On March 15, Dan Davis of ISE updated the Peachtree City Mayor & Council on the status of the Peachtree City Spillway Project. Significant and visible progress has been made, but the project is currently behind schedule by 3-4 weeks due to the full week of freezing temperatures in January and the amount of rain we have had since the project started in September. This has moved the "substantial completion" estimate (when the lake can begin to completely refill) to late June. However, the contractor is working extended workdays and weekends, and if the weather holds, they may be able to regain a week or more. The expected completion of the foundation, when the lake level can be raised by two additional feet, is now late April. 

January 4, 2018 Update: On Schedule, On Budget

View 1/4/18 Presentation (PDF)

At the January 4 City Council Meeting, project manager Dan Davis (Integrated Science and Engineering) reported that the spillway construction is currently on schedule and on budget. Work continues on the spillway foundation this month (note: it must be 45 degrees F or warmer to pour concrete). They hope to be able to raise the lake level by two more feet after this portion is completed (around February), with the goal of having the lake returning to full pool at the end of May while the project wraps up. Work at this time does not include the path bridge that will cross Flat Creek at the Spillway (that is a separate project). 

August 17, 2017 Update

Lake Peachtree Spillway Contract Approved, Lake Lowering Begins August 28

On August 17, the Peachtree City Mayor and Council unanimously approved a $4.387 million construction contract with North Georgia Concrete for the Lake Peachtree Spillway Replacement. North Georgia Concrete built the Lake McIntosh dam and spillway, along with the recent Pye Lake dam replacement in Fayetteville. Fayette County and Peachtree City will jointly fund the project, which was included in the 2017 SPLOST list.

The new spillway will feature a "piano key weir," which allows for the greatest outflow of water during heavy storm events, while preserving the adjacent Kelly Drive/McIntosh Trail bridge. The spillway has been designed to meet the State's latest Category 1 dam specifications (updated in the past year), and the dam will also be upgraded to the Category 1 requirements.

The City will issue the Notice to Proceed for September, in line with the project timeline (at top). The water level of Lake Peachtree will begin to be lowered on Monday, August 28, by a maximum of eight feet. The project is then scheduled to allow for incremental water level increases (by two feet in November after the cofferdam construction, and another possible two feet in February after the spillway foundation has been completed).

While all construction projects of this nature are influenced by the elements, time has been built into the schedule to anticipate bad weather, while minimizing the area of exposed lake bed during weed-growing season. The cofferdam and a corresponding lowering of Lake Kedron by two feet in November will protect the construction area from significant rain events.

During construction of the spillway, a path detour around the work zone will also be required. Traffic on the east side of Lake Peachtree will connect with McIntosh Trail via Fishers Luck. The McIntosh Trail / Kelly Drive bridge will be closed to golf cart traffic, requiring use of the path bridge over Flat Creek just south of the roadway. A new path has been cleared from that bridge back to Kelly Drive adjacent to the Community Gardens. View Path Detour Map (PDF)

The entire spillway project remains on schedule for Lake Peachtree to begin refilling in May 2018, with completion in June 2018.

Project Discussion

Mayor Fleisch discussed the recent history of the temporary spillway repairs and the upcoming Spillway Replacement during her 2017 State of the City Address . . .

April 6, 2017

View Presentation (PDF)

The City's Engineering Firm provided an update on the design of the new spillway, noting that the final design phase was wrapping up and they were on schedule to begin developing the contract documents in May for a June bid. The final design allowed for more detailed engineering estimates based on actual quantities of materials that would be needed. The engineers also recommended decommissioning Fayette County's 50-year old outlet pipe through the dam, which would be replaced by outlets in the spillway (noting that, if the pipe began to leak or collapse, it would require significant digging into the dam, which would be a multi-million dollar project. Trees on the south side of the dam would also be removed as part of the project (tree roots cause fissures and weaken the dam structure).

December 6, 2016

View Presentation (PDF)

The City's engineering firm discussed the status of the project (completion of the preliminary design phase) and updated Council that, due to the location of the new spillway, Lake Peachtree would have to be partially lowered during the construction. The project remained on schedule to begin lowering the lake in August 2017, with a goal of completing the project by June 2018. Council agreed with the engineers' proposal to construct a Thrust Arch style bridge to span the plunge pool below the spillway and include the support design in the initial engineering.

September 15, 2016

View Presentation (PDF)

Staff and consultants recommended what will be the first or second Piano Key Weir designed spillway in the United States. Council agreed and design work is moving forward.

Due to space issues, the old spillway will have to be removed prior to construction of the new spillway, requiring the lake to be partially lowered over the winter months during construction. The project was on track to lower Lake Peachtree and begin construction in August/September of 2017, with construction to be completed in the April/June 2018 timeframe. Cost for the spillway was estimated at $3.5 million.

April 21, 2016

View Presentation (PDF)

Council approved up to $300,000 to fund through Phase 5 (Final Design) of the new spillway. See full project schedule provided.

Project Schedule

(as presented April 21, 2016, with completions noted) 

  • Phase 1 – Schematic Design (Apr – Aug 2016) - COMPLETE
  • Phase 2 – Public Meetings (Aug 2016 – Sep 2016) - COMPLETE
  • Phase 3 – Preliminary Design (Sep 2016 – Dec 2016) - COMPLETE
  • Phase 4 – Design Development (Dec 2016 – Apr 2017)
  • Phase 5 – Final Design (Apr 2017 – Jun 2017)
  • Phase 6 – Contract Documents (Jun 2017 – Jul 2017)
  • Phase 7 – Bidding (Jul 2017 – Sep 2017)
  • Phase 8 – Construction (Sep 2017 – May 2018) - UNDERWAY
  • Phase 9 – Project Closeout (May 2018 – Jul 2018)