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See Council meeting Minutes and City Engineer Reports for related information. Use QuickLinks in the menu on the left side of this page to access those areas. Minutes of the February 18th Council meeting will be of particular interest to those seeking detailed information regarding activity related to Lake Berkeley dam. Also, the FAQ 'Dam, Spillway, Lake' may be of interest. That link is in the FAQ menu on the lower left side of this page.
Update March 9, 2010
Two FEMA representatives came this morning and examined the dam area with the Mayor, the City Administrator, Frank Lombardi, our city engineer, and the Piedmont Geotechnical engineer. All engineers present except FEMA believe the large new crack in the dam surface is additional evidence of major internal damage done in the September storm event. FEMA has completed what they call a “field estimate project worksheet” which they describe as still open to revision before we would need to begin the appeal process. They say they will reconsider their worksheet in light of this development but are making no commitments as yet.
The Mayor continues to work with our federal legislators whose support is much appreciated. She has completed an application for an earmark to the federal 2011 Water and Energy Bill which she submitted to Senator Isakson. We continue to hope that FEMA may become convinced by the available evidence to support the entire scope of the repair effort which they agree is necessary, but so far they have only increased their support level from 11% to @19% of the project. That is certainly progress for which we are grateful, but it’s a long way from what we believe is appropriate. The Mayor has today sent the following significant points for consideration to all our federal legislators:
Berkeley Lake Dam Repair
Significant Points for Consideration
The City and FEMA agree that:
1. The dam was constructed before there were standards.
2. Sometime later, the state created the Safe Dams Program (SDP).
3. Shortly thereafter, around 1978, the SDP inspected Lake Berkeley Dam and found many deficiencies.
4. In 1980, the City renovated the dam to correct the deficiencies. The plans for this renovation followed the Safe Dams Program standards in place at that time, and the project was permitted by SDP.
5. Visual inspections were made on an annual basis thereafter, and in 1996, they noted “wet spots” on the dam.
6. The “wet spots” were investigated by the City in 2008. Hand Auger borings were drilled to see if there was an elevated ground water surface in the dam. There was no indication that the groundwater level inside the dam was elevated.
7. The incident (September, 2009 storm event) occurred, and a slope failure occurred on the dam’s downstream face.
8. After the storm, hand auger borings were made. They indicate that the groundwater elevation inside the dam is elevated.
9. The elevated groundwater is causing the dam to be less stable than is called for by Safe Dams regulations.
10. The internal drain system installed in the 1980 renovation is not working to collect the ground water and pipe it away from the surface.
FEMA’s position is that the incident-related damage is limited to the expressed slope failure area (the part that one can see with the naked eye).
The City’s position is:
1. The elevated ground water surface is lowering the dam’s stability. The lowered stability is what caused the localized slope failure. This is due to the storm event overloading the internal drain system, because investigation into the wet spots in 2008 revealed no elevated ground water.
2. The increased ground water elevation is the problem that must be corrected, or new failures will occur. On March 8, 2010, the City’s engineers discovered a new failure area approximately 4 times the length and to the left (when looking downstream) of the original failure.
3. The reason for the new failure area is the same as the first – the internal drain system has not been functioning since the September disaster event to intercept the groundwater elevation in the dam. This is causing the dam to be less stable than it was designed to be.
4. Additional hand auger borings taken on March 8, 2010 continue to reveal elevated groundwater elevations, which were not present in hand auger borings before the September disaster event.
Click 'read more' to view a chronological list of updates regarding the irregularity at the Lake Berkeley dam.
After the recent extreme rain event an irregularity has been discovered on the face of the Lake Berkeley dam. While we do not expect the dam to fail, in an abundance of caution, we are notifying potentially affected residents about the situation and pointing them to locations, including this one, where additional information may be viewed.
On Thursday, September 24th, our City Engineer met with representatives of the Georgia Safe Dams Program and Piedmont Geotechnical Engineers to investigate a minor slope failure about half way up the face of the Lake Berkeley dam. The failure zone is about 32 feet long and has sloughed off approximately 6 inches. The area immediately down the dam face is wet relative to the other areas of the dam and water 'squishes' under foot, indicating a seepage issue. (Editors note on Oct 26: See the Public Works section of Reports for additional information.)The representative of the Georgia Safe Dams Program felt that the failed area was relatively shallow, likely a result of the interface between new soil placed during the dam renovation in the early 1980’s and the original embankment. The intense rains saturated this upper layer of soil and caused the slope failure.
The representative from the Georgia Safe Dams program made the following recommendations:
1) Monitor the failure zone for movement twice daily. Piedmont Geotechnical Engineers installed a system for reflecting movement and the City is monitoring that system. If movement is detected, the Georgia Safe Dams Program will be notified immediately.
2) Lower the elevation of the lake 10 feet in an effort to lower the pressure on the dam embankment and reduce the seepage through the dam.
3) Consult with Gwinnett Emergency Management Agency to identify the houses which would need to be evacuated in the event that the problem grows.
Update - Sept. 25
Our City Engineer has said the following today:
- The Lake Berkeley dam has sustained some damage as a result of the recent heavy rains.
- The City’s engineers and officials from the Georgia Safe Dams Program have inspected the dam and are monitoring the damaged area.
- Based on the evidence we see at the dam and following the recommendations of the Georgia Safe Dams Program, the City is taking prudent steps to ensure the safety of its residents and to protect the dam from further damage by lowering the lake’s water elevation to lessen the pressure on the dam.
Update #1 - Sept. 28
The dam was monitored twice daily (or more) over the weekend and showeed no additional soil slippage. The City Engineer is consulting with the Georgia Safe Dams Program personnel and additional geotechnical engineers who are experts on issues relating to earthen dams to determine next steps and if indeed we need to continue to lower the lake.
Update #2 - Sept. 28
The City Engineer has conferred with Engineers at Piedmont Geotechnical Consultants and believes that we do need to continue to reduce the level of the lake at the current rate. The fact that there has been no recent movement of soil doesn't mean that it won't move again at some point in the future and the cause has yet to be determined. In the professional judgement of our City Engineer and of Piedmond Geotechnical Consultants, we need to make that determination in a 3-step process:
- The City Engineer would assemble and coordinate a team to peform research about how the dam renovation was performed in the 1980s. They would study all the documents related to that renovation in the Georgia Safe Dams Program office and interview one of our citizens who was involved in that project and who also has offered to help.
- The City Engineer would conduct hand augur testing on the face of the dam.
- If needed, the City Engineer would erect a drilling rig on the dam and drill core samples.
The City Engineer emphasized that he must have the Georgia Safe Dams Program involved in whatever fashion they can manage.
Update - Sept. 30
Our City Engineer, accompanied by an engineer from Piedmont Geotechnical (a company which specializes in dams), has studied documents related to the original construction of our dam and its renovation in the 80s. Yesterday they did some hand augur testing on the face of the dam and will be back tomorrow or Friday to check those augur holes again. Meanwhile, on their recommendation, the city will be installing a second siphon today to bring the lake level down faster. Measurements also continue twice daily by city personnel for soil slippage. None has been detected since the first measurement last week.
Update - Oct. 2
More hand auguring was performed yesterday on the Lake Berkeley dam by Piedmont Geotechnical Consultants and the dam was inspected again by the Georgia Safe Dams agency. City Council has now authorized $5200 for the creation of a very detailed survey of the dam. Our City Engineer has studied many documents about the history and structure of the dam and that information will be included in the survey, but in electronic form. Additionally the new survey will document the slough area, which still hasn’t moved since the initial measurement, and all the augur holes. The surveyors will begin work on Monday. When the survey is completed the City Engineer will begin to design a proposed action plan.
Also on Monday, the Mayor and Mayor ProTem will participate in a briefing with the Georgia Emergency Management Agency in an effort to qualify for federal disaster funds in an effort to reduce costs associated with addressing this issue.
Update - Oct. 6
The surveyors will be back on the dam today and possibly again tomorrow. After that, it will take about a week for them to process all the data and create the survey in electronic form. We have asked our City Engineer to create a preliminary report to present to Council and the public at our next meeting on October 15th including recommendations for additional exploration and possible solutions.
Update - Oct. 15
Click here to view the City Engineer's report to Council on October 15th.
Update - Oct. 22
The City's consultant is currently working with several drilling contractors to price an exploration program that will evaluate the consistency and composition of the dam embankment material. From this data, we will evaluate solutions to the problem.
Update - Oct. 27
Since we are expecting to reach the 10 foot down level today, the company which owns the siphons has been summoned to turn one of them off. They will leave one siphon running to account for incoming water and rain and throttle it back as necessary, adjusting as best they can over time to maintain the level prescribed by the Georgia Safe Dams agency.
Update - Nov. 5
One siphon has been turned off and the remaining one will be throttled back by our contractors no later than tomorrow. They'll have to keep adjusting the remaining one to keep the lake level as close as possible to the 10 foot down mark. Council members and engineers will meet today to discuss a proposal to set up drill rigs on the dam for deeper exploration.
Update - Nov. 15
The next phase of exploration into the dam will involve the erection of drilling rigs on the face of the dam. This will allow engineers to drill down 100 feet into the structure to examine what is happening deep within it. When that information is analyzed, they will be able to formulate a proposal for what should be done to remediate any problems. You should see these rigs being moved into position within the next week.
Update - Dec. 3
December 3rd Update. Before Thanksgiving drilling rigs were erected on the dam and samples taken. Those samples have been examined and the materials were found to be not as well compacted as we would hope. Our engineers have consulted with the Safe Dams agency and recommended that we proceed with additional sampling. Council has authorized that course of action and the additional drilling is going forward.
Update - Dec. 9
The drilling crew has finished drilling the line of holes adjacent to the siphons and Piedmont Geotechnical Consultants is in the process of collecting soil samples for laboratory analysis. The drillers will continue to drill the other lines at the toe and on the face of the dam and collect soil samples for analysis. The drilling crew should finish during the week of December 14th. Soil sample analysis will continue to the middle of January, after which time a report of the results will be compiled and the consulting engineers will discuss repair options.
Update - Dec. 22
Engineers are now completing the deep drilling on the dam and leaving permanent well positions there to allow for future monitoring. Grass seed and hay will be spread to control erosion in the disturbed area. Detailed analysis of the soil samples taken from the borings will take 3-4 weeks to complete. The City Engineer will meet with the council and the public on Monday night, Dec. 28th, at 7:30PM to give a thorough update and answer questions.
Update - Dec. 30
Rich Edinger, the City Engineer, met with Council and the public on December 28th to give a thorough update and answer questions. He noted that the deep drilling and sampling work had been completed on the dam as of December 21st and that all equipment had been removed. The detailed analysis work on the samples taken will take 3 to 4 weeks to complete. He is hopeful that the analysis work will be completed by the January 21st Council meeting and that we can talk about a more specific plan at that time. Preliminary analysis indicates that the soil that was placed on the dam during the 1980 renovation does not have good compaction or consistency and that issue will play into the ultimate solution. Regardless of the solution and repair plan, the lake will have to be lowered further during any construction work in an effort to relieve pressure on the dam. Edinger indicated that the process for dam repair will take approximately a calendar year. See Minutes of December 28th Special Called Council Meeting for more details.
Update - Jan. 21
The City Engineer now has the results of all the lab testing and soil borings that were done. He is refining a repair concept that will be presented to the council and the public at City Hall on Thursday, Jan. 28 at the city council meeting. Also set to attend that meeting are engineers from Piedmont Geotechnical who are dam experts. Interested citizens are invited to attend and will be given the opportunity to ask questions directly.
Update - Jan. 28
Please note detailed information about the ongoing project to repair the dam by clicking on “Dam, Spillway, Lake” in the FAQ menu to your left. Additional information has been available on this website for some time under Reports, Public Works and Minutes of October, November and December 2009 Council meetings in addition to this chronological listing.
Update - Feb. 2
As citizens know, the City has been working on evaluating the storm damage to Lake Berkeley dam and has involved FEMA at every stage of the process, including detailed meetings with the Georgia Safe Dams Program. At a meeting with FEMA and Georgia Safe Dams Program on January 15, FEMA expressed support for our approach to repair the dam, and we were led to believe that they would share the cost of the repair strategy that our engineers outlined. Once the City transmitted the Engineer’s cost estimate to them they decided today that they would not pay for some of the repairs.
The Mayor has been in contact with both of our US Senators and our US Congressman to ask for intervention with FEMA. Citizens who would like to contact their federal legislators may do so as follows:
Senator Johnny Isakson’s FEMA liaison is Nicholas Colella. 770 661-0759,
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Senator Saxby Chambliss’s FEMA liaison is Jennifer Hayes. 706 650-1555,
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Congressman John Linder’s office,
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If citizens make such contacts please copy or notify the city at the following address:
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Update - Feb. 16
The Mayor, City Administrator, and City Engineer met February 16th at City Hall with two representatives of FEMA, one representative of GEMA, and one representative of the the Georgia Safe Dams Program, as well as two engineers from Piedmont Geotechnical Consultants. Also attending at the invitation of the Mayor were staff advisors of Congressman John Linder and US Senator Saxby Chambliss, and Frank Lombardi from City Council. We are most grateful for the interest and support of our federal legislators, and to all the local citizens who contacted them to express their concern and ask for their help. While a resolution was not reached during the meeting, FEMA, our City Engineer, City Staff and the Mayor will continue to work toward an acceptable solution. The Mayor has asked our engineers and the Safe Dams representative to come to a Town Hall Meeting at the Chapel on Saturday, March 13 at 10 AM to answer questions from our citizens. By then we expect to have some more definitive information to give.
Update - Feb 18
FEMA has responded to our request for disaster assistance. Briefly, they are willing to support a “scope of work” on the dam that amounts to only about 11% of what our engineers say must be done, and they fund only 75% of that 11%. In discussion at a meeting this week, FEMA and Safe Dams generally agreed that the entire project described by our engineers must be done for the stability and safety of the dam, so the City will appeal this decision. We believe that we have compelling grounds to win on appeal, and we look forward to continuing to work with FEMA to resolve the discrepancies.
Update - Mar 8
There has been another development on the face of our dam. Piedmont Geotechnical engineers, while making routine checks of the monitoring wells that we have placed in the dam, have found a large tension crack. It is similar to the first movement of earth that appeared just after the rain event that started all this, but it is considerably larger. Our City Engineer, Piedmont Geotechnical engineers, and Tom Woosley of Safe Dams are on the dam studying the problem today. The Safe Dams representative believes there to be no imminent danger, and there are no plans to lower the lake additionally at this time.
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