County expects to wrap up evaluation of options the last week in July, but permits may provide further hurdles to overcome
The Peachtree City Council has formally requested to be kept in the loop on developments surrounding the dam and faulty spillway at Lake Peachtree, which have necessitated the lake level remaining low, leaving much of the surface dry and presenting a less-than-picturesque view of the city’s central amenity.
In a letter to the Fayette County Commission, Peachtree City Mayor Vanessa Fleisch has asked for the county’s engineering studies to be conducted “in a concurrent and expeditious manner so as to expedite a refilling of the lake to its normal pool level.”
The county has provided a timeline to the city that culminates the last week in July with completion of an emergency action plan for the project. However, the timeline for the start of repairs could be extended by weeks or months depending on whether there are any regulatory permits needed from the state or the U.S. Army Corps of Engineers, for example.
The city and county are inextricably linked on the project because the city owns the lake property while the county uses it as a reservoir and is required under a contract to maintain the dam and spillway structures.
The spillway problems, as shown on a high-definition video to council Thursday night, are from a cavern-like void underneath the spillway’s concrete exterior. The cavern was likely caused by erosion, but the net effect on the spillway is that it is structurally unsound, and if the county were to refill the lake … the spillway could collapse.
A big question the county needs answered now — before it proceeds too much further with engineering — is whether state regulators classify the dam and spillway as one that could cause the potential loss of life downstream if they were to be breached and thus cause a flood.
Such a designation is called “Category 1” and would surely mean a costlier fix for the spillway if not an outright replacement, depending on the possible solutions devised by the county’s consulting engineering firm, CH2M Hill and a firm called Golder, which specializes in dam and spillway projects.
If the spillway and dam avoid the Category 1 designation, the repairs are likely to be more affordable. So if the state rules that it is a Category 1 structure, the county will have a window of time to appeal that ruling.
Fleisch in her letter noted that the city “expects the county, in accordance with our agreement, to pay for the costs associated with these studies and any necessary repairs to dam, spillway and associated structures, as well as the costs for removal of any excess siltation deposits in Lake Peachtree.”
“We certainly recognize that these actions will take time to complete,” Fleisch continued. “There is no reason, however, to delay dredging the silt deposits. To begin that process now would show the citizens that our governments are working efficiently and diligently toward a restoration of this important city and county amenity.”
The Georgia Safe Dams program is expected to make its final determination on the lake’s classification by the end of this month at the earliest, and the county in the meantime is conducting modeling of what could happen if the dam and/or spillway were to be breached when it is full, according to County Administrator Steve Rapson.
Rapson has acknowledged that the lake’s low level isn’t looking up to snuff, but he said the county is working on the matter diligently. The lake bottom has been exposed to the open air for so long in some places that grass is beginning to grow.
The lake’s level was lowered earlier this year with a time frame of two months so city residents could perform dock and shoreline maintenance, but it was during that time that the spillway deficiencies were recognized, and the decision was made to keep the lake level low until the matter could be thoroughly checked out.
In addition to the work conducted by the county’s engineering firm, the city also had a geotechnical firm survey the spillway to determine the extent of the problem.
The county is awaiting a report from CH2M Hill on how soon the dredging can be accomplished.
Under a 1966 agreement updated in 1985, the county is required to maintain the dam and spillway through the year 2034 since it is using the lake as a water reservoir.
Councilman Eric Imker was rather brusque Thursday night, urging for the county to go ahead and proceed with a Category 1 spillway design no matter the cost to avoid potential delays in the future.
“I’ve been told this is their number-one priority, but I don’t believe it,” Imker said. “… I don’t want to see waiting until August or September. Now you need to design a type 1 replacement. Get it started now.”
Councilman Terry Ernst said he agreed with Imker.
“What I’ve seen so far, there has been a lot of talk but no action,” Ernst said. “I know government works slow, but we need to get something done here.”
Councilman Mike King asked if the county should have been aware of the spillway’s underground cavern given that the county is tasked with maintenance of the spillway and dam.
The city has hired an attorney to represent it in the matter, given the contract ramifications of the lake usage agreement first created in the 1960s and last updated in 1985.
