Fix the pumps

Thursday, October 15, 2009

Pennywise Part 3

Previously: Part 1 Part 2

[Pardon the copying of verbiage from Part 1 and Part 2 at the beginning of this part. You can scroll down past the main list of 13 features to see the new content]

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.

In part 1 of this series, I introduced the various flavors and features of the Option 1 pump stations as they are laid out in three primary sources:

a) The 2009 Black and Veatch report
b) The 2009 Congressional Cost Report
c) A presentation given by the Corps to the SLFPA-E (east bank levee authority) on October 1, 2009.

See that earlier post for an explanation of the three flavors of Option 1 from the 2009 B&V report.

For reference, here's the description from the Cost Report:
"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."
And here are the renderings from the October 1, 2009 presentation. First, the plan for Option 1:

and the plan for Option 2:

The list of pump station features from the 2009 B&V report is:

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

As I've noted above, we've already covered the first five features. In this post we'll move on to the next 4...

6) All Electric Pumps

This is an odd one. Including all electric pumps (that is, no diesel-powered pumps) makes the pump costs cheaper, but increases the costs of generators, fuel storage, electrical equipment, and associated structural & civil costs around the generator building.

Also, I can't find any evidence the Corps is actually considering putting in all electric pumps. The IER#5, in both its noise and pollution impact sections, indicates some diesel engines for Option 1. None of the pump mixes in any of the Option 1 OR Option 2 scenarios in either the 2009 B&V report (found in Appendix E) or the 2006 GEC/B&V report include an "all electric pumps" scenario. The only place it pops up is in this small mention early on in the 2009 B&V report (and then never again) and - more importantly - in the Congressional Cost Report.

In the Cost Report, it is made quite clear the cost estimates are based only on electric pumps. In fact, that is the first "key engineering criteria:"
"1. Pumping stations could be equipped with a mix of diesel driven pumps and electric motor driven pumps. For the purpose of this report, electric motor driven pumps were used."
No further explanation is given, but here's my guess: the savings from not installing diesel engines is greater than the increased cost of extra generator equipment for all electric pumps. Thus, the costs would look lower. While overall costs would be lower for both Options 1 and 2, it would only matter in the calculations for Option 1, where the Corps wanted to make it look as cheap as possible. The problem is that it doesn't reflect reality: there WILL be diesel engines inside the stations. The Corps simply said to Congress, "Let's just ignore reality for this report, since it'll make Option 1 cheaper."

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

The "future capacity" referred to here is that capacity the Sewerage and Water Board would like to bring online over the next few years. Through the construction of various new pump stations and drainage culverts, the Board anticipates the following increases in carrying capacity for each canal:

17th Street: increase from 10,500 cubic feet per second (cfs) to 12,500 cfs
Orleans Avenue: increase from 2690 cfs to 3390 cfs
London Avenue: increase from 7980 cfs to 8980 cfs

These three pump station features are designed to take into account the future S&WB expansions. However "take into account" can have multiple meanings.

In the 2006 report, it meant that the Option 1 and the Option 2 pump stations had pump capacities which matched the future S&WB numbers. That is, the 17th Street lakefront stations in both Option 1 and Option 2 had 12,500 cfs of actual pumps. And the buildings and generation capacities matched those larger numbers. The same went for Orleans and London.

Now, three years later, it means a totally different thing.

Now it means that space will be provided for pumps needed in case of future S&WB expansion (i.e. 2000 cfs of pumps at 17th, 700 cfs of pumps at Orleans, and 1000 cfs at London), but the actual pumps and everything that goes with them will not. Only the space for extra generating capacity will be provided. That's what the Corps means when they say such things are "expandable," as if that's an actual feature.

Don't get me wrong - it's nice the Corps is acknowledging the reality of expansion that has been in the S&WB capital budgets for years by building structures that can handle the extra equipment necessitated by that expansion. But three years ago they were budgeting for the actual equipment. Now they're not. Why? Cost.

There's another wrinkle. Since the Option 2 pumps will need bigger motors (for the electric pumps) or engines (for the diesel pumps), it would be possible to purchase bigger motors now for the electric pumps and possibly run them at a slower speed or lower load while Option 1 is in place. Note that it's probably not possible to buy bigger engines now for the diesels, since they can't really be run as light as Option 1 would require without damage. The 2009 B&V report speaks to this:
"Large electric motors are more tolerant of the light loading. Thus oversized electric motors could be installed and operated at a reduced load. The efficiency of the electric motor decreases when lightly loaded and as the motor size increases, the motor starting current required will increase. These factors will increase the required onsite electric generator capacity, but the impact on the number of generators is considered minor. If oversized electric motors are provided on the pumps, the engine generators that provide power to the motors will need to be replaced or additional engine generators would need to be installed when the pump station is converted from an Option 1 to an Option 2 pump station."

In addition, it would be possible to include other pump components in an Option 1 station that could be used in Option 2. Again, from the 2009 B&V report:
"Other aspects of the pumps that could be made similar for the Option 1 and Option 2 pumps at an additional cost are the size of pump shaft and bearings and the gear box. Both the pump shaft and bearings can be oversized to function for both Option 1 and Option 2 pumps. In a similar manner, the gear box could be reused for both options provided that the pump speed is the same. If the pump speed varies between Option 1 and Option 2, the gear drive will need to be modified or replaced to accommodate the change in pump speed."

It does not appear the Corps wishes to include many pump components in the Option 1 stations which could be reused in the Option 2 stations. The slideshow from the October 1, 2009 presentation to the SLFPA-E says as much. Page 16 shows what would be done to the Corps' Option 1 stations to convert them to Option 2:

Further confirmation is provided in the red text boxes on the Option 1 rendering:


"Current water surface elevation" referes to the canals as they exist today, which is what will remain after Option 1 is done.

Only the pump housing and the length of the shaft match Option 2 requirements:


As you can see, much of what they are planning to install on Option 1 will have to be replaced in Option 2, including gearboxes, motors, impellers (that's actually to be expected) and electrical switchgear. With clever planning, much of that equipment could be purchased in Option 1 with an eye toward Option 2, saving money down the line.

However, the rule of the day with the Corps' version of Option 1 is to save money now, and don't worry about future costs. It's quite shortsighted and makes bringing Option 2 to fruition much harder, since it will be unnecessarily expensive down the line.

Next: Part 4
Previously: Part 1 Part 2


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