Many residents of the Stoneybrook community have been left wondering why their streets were flooded for several days after the large storm this past weekend while the rest of Gateway’s roads cleared up rather quickly.
So when a professional environmental engineer contacted me to tell me he had visited the scene in person and could explain everything, I obviously was eager to take the meeting.
Basically, the engineer’s explanation can be easily understood with this simple analogy: When you try to empty a sink but the drain is partially clogged, what happens? The water stays longer than it should, based on how badly the drain is clogged.
Using Google Earth, this engineer showed me precisely how the pond system works in Stoneybrook. All rain water in that community goes from one pond to the next, generally in a southwest direction, eventually making its way to a basin just south of the western tip of Pebble Stone Drive. The water then exits Stoneybrook through an “outfall control structure” and goes in to a pond at the northern end of Gateway Greens. From there the water makes its way to the next pond… to the next pond… to the next pond… and so on.
What you see in the picture associated with this article, which was taken this past Sunday, is that outfall control structure taken from the Stoneybrook side. What you also see is a pile of debris immediately to the left of the structure.
What you don’t see is that below the water line there is a 6 foot wide by 6 inch high orifice where the water gets out whenever it reaches a height of 22.5 feet above sea level. The top of the concrete portion is 25.9 feet above sea level, for reference. By deliberate design, all ground level floors in Gateway must be built at a minimum elevation of 26.7 feet above sea level.
But what you also don’t see in that picture is that on the OTHER side of the structure, the water was “two feet” lower on Sunday, according to the engineer I spoke with. And the water wasn’t flowing through nearly as fast as it should be, again according to the engineer.
Supervisor Ed Tinkle (himself a retired civil engineer) also went to visit the Stoneybrook site at a different time. When Tinkle and I spoke on the phone yesterday, I relayed the feedback from the engineer I met with, and Tinkle concurred with the above assessment on both fronts saying he saw the same thing himself.
Additionally… as you might imagine… the Gateway District has its own engineers – a firm named Tetra Tech. That company has two main people that are essentially referred to as the District Engineers. One of those people is Tyler Wainright. (The other is Danny Nelson.)
In an email that Wainright wrote to Tinkle, District Manager Chris Shoemaker and Public Works Manager Mike Tisch, Wainright said: “To me, it did not look like the outfall weir was flowing at full capacity through the rectangular orifice. It looks like there aren’t any trash baffles over the orifice, so it could become have [sic] partially clogged.”
So that makes three credible engineers, two of them (Tetra Tech and Tinkle) specifically paid to represent Gateway’s interests, who agreed that the water flow was not what it should be out of Stoneybrook.
Since multiple GSCDD sources shared this email from Wainright with the Gateway Sun (and it became a public document the moment it was sent to Shoemaker anyway), I forwarded it to the engineer who contacted me. He agreed whole-heartedly that a “trash baffle” in that location was a great idea.
I don’t know what a trash baffle is, and you don’t know what a trash baffle is. But Wainright and the independent engineer both know what a trash baffle is, and they both seem to think there should be a trash baffle there, so how about we get one installed next dry season? Everyone agree?
Here’s where things get tricky.
The engineer who contacted me showed me a heavy-duty rake leaning up against a wall in his office. He said he got on top of the weir and began feeling around the orifice with that rake, and he was 100% sure there was blockage present that was preventing some of the water from flowing through.
Wainright in his memo said the same thing about there likely being blockage, although he based his opinion purely on the lack of flow he observed.
But when I contacted Shoemaker to find out if the GSCDD sent someone out to the weir, and if so, what kind of debris they found blocking the orifice… he said there wasn’t any.
The only thing they found was a turtle that had gotten stuck, said Shoemaker.
Shoemaker via email: the only “blockage” we found in the orifice was a small turtle, no other debris or trash and that was on Monday.
Circling back to the picture (again, taken Sunday)… I already pointed out the large pile of debris immediately to the left of the weir. The engineer I spoke with surmised that when the district staff was in the area prior to the storm performing a cleanup, it’s possible they put the debris there in an area well above the normal water line that they never imagined could ever be reached. But the engineer’s theory is that when the water did reach the debris, the drain effect swept the debris toward the orifice, partially clogging it at some point, thus preventing the water from leaving Stoneybrook at the designed pace.
But again, Shoemaker rejects that because he says that his staff was there on Monday and that there was no blockage, except for the small turtle.
Shoemaker did not provide an alternative explanation as to why water did not recede in Stoneybrook like it did everywhere else.
The topic will obviously come up at the next GSCDD meeting on September 7. Perhaps someone will ask Shoemaker that if it wasn’t blockage, what was it?
I really wanted to publish this article yesterday, but I was thrown for a loop when Shoemaker said there was no debris discovered that was blocking the water flow.
Quite honestly, I didn’t even know what to do with that statement.
So I racked my brain, wondering what else could possibly have slowed down the flow of water out of Stoneybrook? After-all, every other community drained properly except for Hampton Park in certain spots, but those spots are very close to construction sites where they deliberately blocked the drains. So those pockets of standing water are explainable.
But how do we explain what happened in Stoneybrook?
Then it hit me.
Maybe George and Kathleen Flaherty, seeing the rising water levels and sensing the concern in the community, combined their mental powers in an effort to alter the quantum reality and the scientific properties of the water in Stoneybrook in order to force it to flow out faster than physics would normally allow.
But they messed up!
And what ended up happening was the Flaherty’s mind energy altered the water in such a way that it actually flowed much SLOWER than it should, thereby leaving Stoneybrook flooded for days.
So either I’m right, and it was the Flaherty’s fault, or the drain was partially clogged and the water couldn’t get out.
Here’s what’s going to happen next Thursday. And I’m saying this because I’ve read Tetra Tech’s email, and I’ve watched all these people operate for nearly three years now.
Tetra Tech going to get up and tell the Board of Supervisors that this was just an epic rain-fall. They’ll even use the term “25 year storm” because the amount of rain fall that came out of the sky over the three day period statistically only happens once every 25 years.
Then they’ll cite the schematics which state the ponds in Gateway were only designed to handle 11.5 inches of rain over a three day period, and despite the fact that Lee County’s official rain counter thingies calculated right around 11.5 inches from the storm at most of its stations, they’ll still say it was a design issue.
Everyone’s ass will be properly covered, and everyone in the room will assure the public that improvements will be made for next time this happens.
From Wainright’s email: “Bottom line is that the streets were not designed to handle that much rain.”
Then why weren’t the streets flooded with a foot of water for 2 days in in Silverlakes, Royal Greens, Gateway Greens, the schools, Bristol Parc, Cypress Pointe, on Griffin Drive, the 7/Eleven, Timber Ridge, Daniels Preserve, at Ed’s Fit Camp, Devonshire Lakes, on Gateway Boulevard, etc.
Why only Stoneybrook if the problem was that the streets were not designed to handle that much rain?
Look, I completely understand that there’s a dark cloud that hovers over Stoneybrook 24 hours per day bringing misery to all who live there. I call her Margaret Fineberg. But I’m telling you, the flooded streets were not her fault.
Three engineers all said they looked at the outfall control structure where water flows out of Stoneybrook, and all three said the water wasn’t pouring out nearly fast enough. It’s not hard to understand what happened here, guys.
It wasn’t the amount of rain.
Because if it was the rain fall, all of the communities would be flooded. Not just one.
My guess is that the independent engineer was bang on.
I believe district staff worked to clear the site in preparation for the storm, but they underestimated the water level that was about to hit the area and they just piled the debris off to the side, above the expected water line. Because if human beings didn’t place that pile of debris there, then we must conclude that the storm’s rising waters gathered all that debris on its own… and placed it all nicely in a perfect little pile… directly beside the weir… exactly at the height the water would eventually rise to.. while at the same time believing the same water currents didn’t bring any of that debris toward the orifice.
Remember when you were a little kid, and sometimes while you were in the bath tub you would lift the plug up slight amounts and observe the water drain at different rates. You liked to listen to the sounds, didn’t you? But you also noticed that the more you lifted the plug, the more water would go down the drain. When you lowered the plug and/or blocked the drain, less water escaped. Use that life lesson.
And did you also notice that the water began receding much more quickly on Monday, when Shoemaker specifically said he had people at the site? Hmmm.
Unfortunately, rather than trying to actually learn from this incident, the Board of Supervisors will once again transform in to bobble-head dolls capable only of nodding quietly when Tetra Tech blames it on the rain.
Because whatever you do… don’t put the blame on you…
I’ll let the independent engineer who contacted me bottom line it for us: “There is no doubt that this was a major event and some amount of flooding would have occurred regardless. However, the fact that the drainage system was not working at full capacity because of obstructions made things worse than they had to be.”
Sums it up.