re: Storm Watch- Gulf- Tropical Depression- Northward Miss. Valley

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max sustained 40 mph lmao

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Without question a strengthening storm at landfall has the potential to surprise you.

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How did this strengthen to a TS while sitting on Yucatan for 2 days?

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It’s extremely hard to tell. 20 miles east could put Baton Rouge into the calm or 20 miles more westward and it could put Baton Rouge in the worst. Nobody will know until this happens. It’s gonna have to be a real time call to be honest.

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6-10 inches in Nola will be interesting considering the pumps ain’t working that great

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According to the pre-hurricane season press conference on May 29 and a series of tweets from S&WB today, all non-exploded turbine-generators are available, as are all 99 main drainage pumps. They note they will be using the 25 Hz electromotive diesel (EMD) generators at the Carrollton Plant during this storm. This would be because they don't have enough power from just the 25 Hz turbine-generators, especially turbine-generator 3, which continues to lose capacity. The latest actual update with data shows turbine-generator 3 has dropped to 6 megawatts from 7, which is actually half of its nameplate 15. The reality is according to logs of large storms over the past few years, there's usually an average of 20-24 pumps that go out during an event. Pumps that can go out due to wind or lightning include all pumps powered by Entergy's 60 cycle power - which is fed on overhead lines - as well as those pumps powered by 25 cycle power which the S&WB feeds by overhead lines from their frequency changers (the frequency changers convert 60 cycle Entergy power to 25 cycle power). Then there's possibility of pumps going out due to electrical faults in the S&WB's subsurface electrical feeders, mainly due to those feeders being, for the most part, decades old and run at voltages higher than they should. There's also the possibility of the largest horizontal pumps not being able to be "loaded" (i.e. start water flowing through them) because vacuum pumps which provide the initial suction through the water pumps are malfunctioning, or there are holes rusted through the pump casings causing leakage. There's also the possibility of power being refused to pumps because it is constrained. In the particular case of drainage pumping station 1 (which is what I assume you are referring to), there are nine main pumps used for drainage. Seven are the large horizontal pumps most people think of when thinking of drainage pumps, while two are smaller vertical pumps. Of the seven large pumps (labeled A through G), five (pumps A through E) are 25 cycle, while the two others (F and G) are 60 cycle. The two other smaller vertical pumps are also 60 cycle. There are two much smaller pumps used for constant duty service in dry weather. DPS 1 is one of the stations whose discharge channel is smaller than the capacity of the pumps which feed it. S&WB spins this liability into claiming there are "redundant" pumps there. In general, the Entergy-powered pumps are turned on first, since they are powered independently of S&WB's turbines. That is, pump operators do not have to contend with getting permission from the 25 Hz power dispatchers at the Carrollton Plant, who are distributing power among eight stations which use 25 cycle power. Fortunately for those served by DPS 1, pumps F and G happen to be the two largest pumps in the entire system by nameplate rating, at 1200 and 1215 cubic feet per second respectively. They are also able to be run by the S&WB's 60 cycle turbine-generator 6 via underground cables installed in 2017. The switchover from Entergy to T6 should take about 10 minutes, assuming T6 is running. Sketchy details from the May 14, 2020 storm indicate this did not happen, since it took about 45 minutes to restore power. We do not know if T6 was running that night or not, but S&WB claims it is ready now. There is one caveat about pumps F and G, though. While their nameplates are the highest in the system, their actual capacity is somewhat degraded, according to testing performed by Veolia in 2017 and 2018. That testing showed that pump F moves about 76% of its nameplate (or 907 cfs), and pump G moves about 89% (or 1084 cfs). This is still a considerable amount of water to move, and only two pumps in the system move more than pump G, but they are not flowing at what the S&WB claims in its public communications. Overall, according to Veolia's testing, DPS 1 moves about 84% of its total nameplate rating. This is pretty good, considering the beating S&WB puts its pumps through (by operating them until they run dry, which causes all kinds of damage, rather than setting a minimum submergence), and the unique "feature" of drainage pumping station 1: it has no trash screens to prevent debris from running into its pumps. I know that last one might seem shocking, but it is painfully obvious once one looks at the station from the inlet (MLK Blvd) side and sees there are no trash cleaners like one sees on the front of other stations like station 6 on the Orleans/Jefferson line. It's a miracle more pumps have not been destroyed by the complete lack of protection from anything that can flow through the underground drainage system. Considering we have seen that entire cars can fit in that system, this is truly providential. As to what happened during the May 14 storm, I am awaiting the pump and power logs through the public records system at S&WB. They are supposedly due to me on June 16, but I put in the request on May 19 and it doesn't take a month to collect these records, so I'm pretty sure they are just stalling. Given that I have records requests outstanding from last August, I'm on certain ground with that supposition. According to the Veolia testing, DPS 1 is in relatively good shape capacity-wise. So is the station downstream of DPS 1, which is DPS 6. Its percent capacity is about 87%. Many other stations are not as fortunate. Perhaps the poster child would be station 4 in Gentilly (at Prentiss and Warrington). Its capacity is a measly 58%, with two of its three large pumps moving less than half their design capacity (the third could not have a successful test performed by Veolia, but it is likely in just as bad a shape). Station 12 in Lakeview, with its single 25 cycle pump, is also woefully under capacity, at 42%. These are figures the S&WB released in partial form in 2018, but never really incorporated into their public communications. They have continued to use the nameplate ratings rather than speaking in terms of the actual pumping capacities they spent oodles of dollars to find out. Even worse, some of the nameplate ratings they cite publicly are even wrong. For example, they call out pumps F and G at DPS 1 at 1100 cfs. As you can see from the attached picture of the actual nameplate from pump G, that's wrong. It clearly says "1215 cfs."

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