Fix the pumps

Thursday, October 15, 2009

Pennywise Part 1

The largest refrain from those in support of Option 2, which is everyone but the Corps, is that effective flood protection is better than cheap flood protection. Supporters of Option 2 say it is just plain better than Option 1, a position even the Corps agrees with in a technical evaluation report mandated by Congress. The problem New Orleans and the surrounding area faces is that the Corps is cheaping out and going for Option 1 over Option 2, which is exactly what the Corps chose to do just months after Katrina, even though they believed it would only take another $190 million to do Option 2. Admittedly, it may have cost a little more to do Option 2, but based on the facts at the time - and what was passed up the chain to the White House and Congress - the Corps CHOSE to do Option 1 to save $190 million, and drafted the authorization and appropriation language to match it. The cheaping out began a long time ago.

However, I would go further and say that the Corps is cheaping out even on how they are planning to build Option 1. I believe they are deliberately lowballing the Option 1 estimate in order to make it look like the only way to go. They are doing this through a combination of shifting some features to future Option 2 and simply not building other features. If they didn't, it would be revealed that even Option 1 - if it was truly to be built correctly and be adaptable to Option 2 - cannot be built for the $804 million the Corps told Congress to give it.

While they redacted nearly all the costs out of the 2009 Black and Veatch 90 Day Study, the Corps legal eagles still left all the technical information intact. The 2009 report is the backup for the 2009 Congressional Cost Report, which is the bedrock document for the Corps' cost estimates. That B&V technical information tells a pretty disappointing story that was left untold during the public comment period of IER #5 in May of this year.

First, I should explain that the 2009 B&V report breaks down Option 1 into 3 flavors:

a) Non-adaptable Option 1 is the easiest to understand. It is the cheapest way to go. The inlet basin and foundation of the stations would not be lowered to match a future Option 2 bottom-of-canal grade, and there would be no features included to make future Option 2 any easier or cheaper. The Corps does not seem to be going this route.

b) Base adaptable Option 1: this appears to be closest to what the Corps is doing, though there are differences. It is essentially the Non-adaptable Option 1, but with a deeper foundation and sill to accommodate future deepened canals in Option 2. However, many other features which would make this flavor adaptable are not included.

c) Robust adaptable Option 1 is the one that New Orleans should really be getting. In addition to the deepened foundation and sill, it also includes many features that would quicken and cheapen the future conversion to Option 2. A few features from this flavor appear in the Corps' latest Option 1 plans, but mostly this does not appear to be the way the Corps is going, probably due to cost.

The Corps has picked and chosen from the various features of these flavors to make a melange of Option 1. Without the costs of each feature (redacted out of the main text of the 2009 report, while similar figures remain in the 2006 report main text), it's difficult to determine exactly why they chose certain features over others. The best I can do is document what we know now, and give my best shot on their reasoning.

The 2009 B&V report gives a summary of all the features available for each flavor of Option 1 on Adobe page 72:

1) Deepened Sill
2) Pump Station Sized for Future Pump Capacity
3) Pump Capacity Sized for Future Pump Capacity
4) Formed Suction Intake
5) Fuel Storage and Generator Sized for Future Capacity
6) Canal Transitions
7) Includes Breakwater
8) Stilling Basin at Discharge
9) Includes Gated Bypass
10) Includes Floodwall/Levee Upgrades
11) All Electric Pumps
12) Includes Siphon Recovery
13) Removal of ICS Facilities

This list provides the best framework for discussing the details of the planned Option 1 pump stations. Note that some of these are not features per se, but rather choices. For example, number 6 - "canal transitions" - refers to whether the transition from the existing canal bottom (which will be preserved in Option 1) to the inlet basin of the new Option 1 stations is abrupt and short or long and smooth.

Anyhow, the Corps has thrown the public a bone by saying that while they don't support Option 2 (excuse me, they claim Option 2 is "not authorized" even though the language of the authorization explicitly says they can "modify" the canals), they will nonetheless be including features in the Option 1 stations which make them "adaptable" to make Option 2 easier (and thus possibly cheaper) in the future.

It's a nice thing to say, but how true is it? What features on the above list are actually going in the as-publicized Option 1 stations? And which are not? Are there truly "adaptable" features in the proposed Option 1 stations, or are there features which will need to be ripped out for Option 2? And are there features which should be in the Option 1 stations but have been pushed off to Option 2?

Besides the 2009 B&V report, there are two authoritative sources for what the Corps wishes to do with the Option 1 stations. One is the 2009 Congressional Cost Report, which is based on earlier drafts of the B&V report. The Congressional Cost Report includes a detailed paragraph describing the Option 1 stations:
"Pumping Plant - The pumping stations include the pumping station building and equipment, intake wet well, discharge section, canal transitions, generators with enclosures, a tank farm, and all the ancillary systems required for a fully functional facility. A cofferdam is required for the contruction of the pumping station. A temporary bypass may also be required to route canal flows around the cofferdam during construction."

The second source showing the Corps' Option 1 intentions is a slide presentation given to the SLFPA-E (the east bank levee authority) on October 1, 2009. It includes quite a bit of information which, when combined with the 2009 B&V report and the Cost Report, may allow us to figure out some things.

Here's the rendering of the Corps' Option 1 proposal from that presentation:

And here is the rendering of future Option 2:

I'm going to work through the various features of the station shown in the three sources using the list from the 2009 B&V report and figure out what's in and what's out. The easiest way for me to do this is to work from the inlet of the stations to the discharges. So let me rejigger the features list and work through it one by one.

1) Includes Floodwall/Levee Upgrades
2) Includes Gated Bypass
3) Canal Transitions
4) Deepened Sill
5) Formed Suction Intake
6) All Electric Pumps
7) Pump Station Sized for Future Pump Capacity
8) Pump Capacity Sized for Future Pump Capacity
9) Fuel Storage and Generator Sized for Future Capacity
10) Includes Siphon Recovery
11) Includes Breakwater
12) Stilling Basin at Discharge
13) Removal of ICS Facilities

In this post, I'm just going to concentrate on numbers (1) and (2) on the above list. Subsequent posts will work further through the list.

1) and 2) Includes Floodwall/Levee Upgrades and Includes Gates Bypass

These two items belong together, since they represent a choice. The "floodwall/levee upgrades" refer to the need to fix the outfall canal walls if gates are installed in the Option 1 stations. If there are no gates, water would only rise in the canals from rainstorm water when the city's interior pumps were turned on. That rainwater would be immediately evacuated by the Corps' pumps at the lake ends of the canals. The installation of gates allows storm surge into the canals before the gates are closed but while the city's pumps are running, increasing the risk for a breach.

The easiest parallel would be to imagine the current gates sealed permanently closed, essentially turning the canals into very long bathtubs. The only water coming in would be from the city pumps, so the Corps pumps would be turned on every time there was rain. This would increase the cost to run the Corps pump stations. However, there would be no risk from storm surge flooding (barring backflow through the Corps' pumps), since there would be no open gates through which surge could flow.

There is a certain appeal to this scenario, since the possibility of exceeding the safe water levels in the canals is considerably reduced. However, since the walls and levees along the London Avenue canal are built on such sandy soil, and the safe water level there is so minuscule, the risk of canal breach along that canal still exists even without gates, and work would still need to be done on those walls anyway. The same situation exists to a lesser degree along the 17th Street canal, where the safe water elevation is slightly higher than at London Avenue.

That is what one of the redacted appendices in the 2009 report - Appendix F - is all about. It lays out a lot of calculations which weigh the cost of increased Corps Option 1 pump operation (i.e. Option 1 stations with no gates) vs. making needed repairs to the canal walls (i.e. Option 1 stations with gates). The appendix is a very dense read, but it basically boils down to the rather cold financial calculation of whether it is cheaper to fix the walls or run the future Option 1 lakefront pump stations all the time. It's quite chilling to read, frankly. One of the creepiest sentences is this one: "Most of the advantages and disadvantages have cost implications, so the decision to provide gates for full or partial flow or no gates at all is primarily an economic one." Yikes.

Like I said earlier, the interesting thing is that it doesn't matter what they do on London Avenue - they have to fix the walls because the money and flow numbers don't work out either way. If there's gates, the danger from storm surge and high tide puts the London Avenue walls at risk. If there's no gates, the danger from stormwater outflow from the city puts the London Avenue walls at risk. And the situation at London is likely worse than Appendix F states. That's because Appendix F assumes that the current 5 foot Safe Water Elevation only extends along the northern half of the canal. For some reason, they call out the Safe Water Elevation along the southern half of the canal as 9 feet. I have confirmed with the Corps New Orleans District Operations Division that the London SWE is 5 feet along the entire canal.

The Corps has chosen to install gates on the Option 1 stations. According to the 2009 Appendix F, this also means they should be improving the walls along the London Avenue and 17th Street canals. However, according to the Congressional Cost Report, they will not spend any money on Levees and Floodwalls in Option 1:

This is disturbing. Their own report tells that if they install gates, which they are, they need to upgrade the walls at London and 17th. But they've made the decision not to make those upgrades. Very disturbing indeed.

What's even more troubling is that we're not talking about a ton of money here to upgrade the remaining walls. According to Appendix F, if gates are installed it would only cost a relatively paltry $118.8 million to replace the I-walls with T-walls along vulnerable sections of the 17th Street and London Avenue canals (the Orleans Avenue canal can already handle high water levels and does not require any wall replacement). And that is a worst case number. It includes a 20% contingency and comes from a extreme hydraulic requirement of filling the canals completely up to 8 feet in depth. With those repairs, that 8 feet would be the new safe water elevation along the 17th Street and London Avenue canals (up from 6 feet at 17th and 5 feet at London)

Yes, the Corps could fix the walls along the existing canals and make Option 1 far, far more palatable to the public for about $120 million. However, thus far they've made no moves to do so. Instead they continue to study the safe water elevation, with results not due until the beginning of the 2010 hurricane season. They also claim that Option 2 is far too expensive, but what Appendix F shows is that they could do Option 1 with canal wall replacements for a fraction of the Option 2 cost and still end up with a pretty safe system that could be upgraded to Option 2 later.

Naturaly, that's not going to happen. They want to save pennies while the city crosses their fingers every time the lake is at high tide and it rains hard.

Next: Part 2
Followed by: Part 3 Part 4


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