BIG CANOE, GA — In high-hazard infrastructure management, engineering decisions must be based on hard, objective science. Yet, a look at decades of state-mandated documentation for the Lake Petit Dam reveals a pattern of risk management by Geosyntec that looks more like willful blindness at best, and engineering malpractice at worst.
For nearly twenty years, the response from the Big Canoe Property Owners Association (POA) and their engineering consultants (#Geosyntec) regarding wild, shifting underground water pressure has been to look away. Instead of verifying the data, consecutive reports use the exact same word-for-word disclaimer, guessing that the spikes “may be an indication that the instruments are becoming unreliable.”
Hiding behind the word “may” means they admit they don’t actually know if the dam’s core is failing or if the tool is simply broken. Using a potentially faulty sensor as a twenty-year excuse to ignore alarming numbers isn’t science—it is a defensive strategy designed to delay an uncomfortable truth.
A Twenty-Year Alarm Built on Hard Numbers
To understand the danger of ignoring this sensor, look at the chronological trail of Piezometer G-2 Shallow—the instrument drilled directly into the dam’s core:
- 1998–2006: The water pressure inside the core maintained a steady, predictable baseline.
- 2007: The well water level suddenly surged, but it was labeled a temporary glitch.
- 2013: The internal water table took a permanent step upward.
- 2020: The sensor recorded an all-time historic high, marking a massive 9.72-foot vertical spike from its original design baseline.
- The Ongoing trend: G-2 Shallow fluctuates at double the rate of every other well on the dam—clear evidence that a unique internal pathway has formed in this specific zone, despite being casually written off by management. To justify ignoring it, they simply copy and paste the exact same boilerplate comment report after report, conveniently blinding themselves to how this data perfectly correlates with the expanding wet spots on the dam face:
“PZ G-2 Shallow data tends to be more reactive in a given period, showing fluctuations on the order of twice what the remainder of the PZs exhibit. While these trends are not currently considered a dam safety concern, data for the G-2 series of instruments should be reviewed carefully in subsequent measurement intervals to determine whether the trends accurately reflect conditions in the embankment and subsurface or may be an indication that the instruments are becoming unreliable.”
The Million-Dollar Cycle of Failure
Big Canoe has been paying engineering firm Geosyntec huge sums of consulting & engneering fees – almost $3 Million since 2021. Yet, after spending a combined project total of almost $8 million on capital dam projects over recent years, property owners are dealing with almost the exact same structural problems we faced when we started – maybe worse!
Continuing to collect massive fees while leaving a critical core indicator completely unverified looks less like sound engineering and more like malpractice. Replacing a suspect shallow sensor is an entry-level job that takes just 1 to 2 days and costs between $8,000 and $15,000. Spending $10,000 represents a tiny 0.1% fraction of our expenditures. Why hasn’t it been done? Because a brand-new, certified sensor recording these exact same 9-foot surges would instantly strip away their “faulty tool” excuse, forcing state regulators to declare a progressive structural problem.
Connecting the Core Pressure to the Expanding Leaks
When you analyze the physical layout of the dam, a clear cause-and-effect relationship emerges:
- The Source: Piezometer G-2 sits directly on Bench 3, logging high internal water pressure.
- The Blockage: Directly downstream, the original 4-inch underground slope drains were only partially dug out—leaving the top sections unexcavated and rotting up the hill—while the main 10-inch drainage line they connected to was cut and plugged with solid rubber caps.
- The Path: Because those old internal pathways are now trapped and capped, the pressurized water is forced into the surrounding soil along the path of least resistance.
- The Eruption: The pressurized water tracks straight through the slope face in this area, erupting as an expanding, waterlogged blanket above Bench 1 that has grown to 25 feet high, and below Bench 1 to 60 feet wide.
*This correlation highlights the most crucial piece of data in the entire file: the precise layout of the infrastructure. Lake Petit Dam is a massive asset monitored by dozens of different sensors. Yet, the single instrument ringing alarm bells happens to sit directly upstream of the exact zone where the surface is visibly saturated and expanding. Connecting these two realities doesn’t require an advanced engineering degree—it just requires common sense.
This indicates a high probability of internal piping—the classic process where water cuts micro-conduits through the clay core and erodes the dam from within.
The Next Engineering Trap: Higher Bench Drains
As water continues to bypass the previous Bench 1 modifications, property owners must brace themselves for the next predictable engineering proposal: an internal drain at a higher level, like Bench 2 or Bench 3.
Do not fall for it. Basic physics dictates that a higher bench drain will act as an accelerator for a dam facing progressive internal piping. Right now, the partially dug-out pipes and plugged endpoints create a choking effect, providing a small degree of stabilizing backpressure. If engineers drill a new drainage system higher up, they will instantly relieve that backpressure. By creating a wide-open exit ramp, they will radically increase the speed of the water cutting through the core, washing away fine soil particles and hollowing out the dam’s foundation from within. While the engineers hope a higher drain will finally dry the surface and hide the problem, messing with these trapped internal pathways will backfire—exactly like what just happened with the first project on Bench 1, where the water simply bypassed the new pipe and caused the surface wet spots to explode out to 25 feet high and 60 feet wide.
The Ultimate Cost: A Ten-Million Dollar Monument
We are currently being prepared for a massive capital assessment to completely replace the principal spillway chute—a project estimated at $9 million and climbing.
But property owners must look at the big picture of this financial strategy. If the core of the earth-fill embankment is actively unraveling from within, continuing to hand millions to Geosyntec for an external concrete spillway is a catastrophic waste of money.
We could easily end up funding a state-of-the-art $10,000,000 spillway, only to have state regulators turn around a year later, audit the failing embankment core, and declare the entire structure completely unsafe. The dam face would either have to be completely rebuilt from scratch, or the lake would be permanently drained by regulatory mandate. We would be left with a multi-million dollar concrete monument, but no lake left to enjoy.
We need the POA to finally call their own bluff. We need immediate, independent verification of whether the G-2 piezometer is actually faulty, and if it is, it must be replaced immediately. Either way, property owners have an absolute right to know the scientific truth about the true lifespan of this dam while we still have the capital reserves to make an informed choice – rather than blindly funding the next $Million Dollar Bandaid.
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