Fix the pumps

Friday, December 04, 2009

Poundfoolish, Part 1

Update - 12-9-09
Video of the December 9, 2009 City Council committee meeting is available here

[Update - 12-8-09
The Corps' appearance has been moved to Wednesday, December 9th, at 2 PM CST as part of a joint Recovery/Public Works City Council Committee meeting. The Corps is the only item on the agenda here. The meeting will be streamed on the City Council's website here.]

[NOTE: The Corps will be appearing before the New Orleans City Council on December 7 to speak about their $90 million work on the outfall canal walls, which is supposedly not actual modification. They will also be asked about the over half billion dollar property tax increase Option 1 drops on New Orleans over the next 50 years.

The press release is here. The agenda is here. Live video will be available here on the day of the meeting.]

At the November 19, 2009 meeting in which Colonel Sinkler revealed the Corps is planning on spending $90 million modifying the outfall canal walls and levees (despite their staunch adherence to the "we're not authorized to modify the canals" talking point), the Corps released part of the Phase One Request for Proposals for the permanent pump stations. It is a scope of work, with design criteria. The Corps' consultants, Black & Veatch, refer to it as a "Statement of Work." I'm going to call it a Scope of Work, which is the more common term.

Releasing this sort of thing for comment is not unusual, despite how the Corps might portray it. The difference is allowing the public to see it. Usually it is public agencies and contractors that get a sneak peek before it is officially issued. This particular document has been floating around behind the scenes since about March of this year. Note that the revisions (in the lower corner of each page) are already at "K," meaning this is at least the 11th version of this document.

As with many documents the Corps releases, parts are missing. At least three appendices ("A" through "C") are not included. Also, this document represents but a small sliver of the overall RFP. Among the things missing are drawings, other technical specifications and all the commercial terms, which together would likely dwarf the 82 pages released to the public by a factor of five.

Overall, I would call the document "choppy." You have to look in multiple places for some things, and there's a lot of vagueness where there should be certainty.

I thought I would go through the features I reviewed in the earlier "Pennywise" posts (Parts 1, 2, 3, and 4) and see how the Corps/Black & Veatch is specifying them. I've rejiggered the list a little, but the links still point to the correct posts.

1) Formed Suction Intake
2) Includes Floodwall/Levee Upgrades
3) Includes Gated Bypass
4) Canal Transitions
5) Deepened Sill
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

Formed Suction Intakes, Spare Pumping Capacity, and Taxes

The area around the pump inlets is the best example of how Corps cost cutting gets out of control, and actually harms projects.

I wrote quite a bit about pump inlets in Pennywise, Part 2. To review, the Corps does not wish to install Formed Suction Inlets (FSI's) on the inlets of the Option 1 pumps, even though they would save costs in the future and make eminent sense to put in now. They wish to simply leave the pump inlets bare, similar to a straw in a drink. Formed Suction Inlets will be required in Option 2, when the canals are deepened. That is because they are the only inlet design (according to the Corps) that can handle the shallower depths of water that will come with the deeper Option 2 canals.

The Corps installed FSI's on the direct drives at 17th Street and London Avenue in 2007. They provided a graphic in the February 21, 2007 Task Force Hope Update:

The newly released Scope of Work codifies the Corps' twisted reasoning, but provides an even more dangerous dimension to the problem.

Here's the relevant verbiage on pump inlets (ironically found in the section of the Scope dealing with adaptable features):
"PPS [Permanent Pumping Station] pumping station inlet, intake area, and gate structure [shall be] designed to accommodate Possible Future Condition pumps without structural modifications to the pumping station. Note that addition of formed suction intake (FSI) structures is not considered a structural modification if they can be added without demolition of the initial pumping station structure and if they can be added without requiring a pumping station shutdown. Shut down of an individual pump during modifications is permitted."

Taken in isolation, this statement might seem reasonable. But one needs to also consider that the Corps does not plan on including any spare pumping capacity beyond the bare minimum required to match the existing pump stations' flowrates (based on current flows at all three canals and future S&WB expansions at 17th Street and London Avenue). So without any spare pumping capacity, how exactly would a future pump-by-pump shutdown impact the ability of the Sewerage & Water Board to drain water from the city during a storm event? It would harm it, severely.

This is horrible, cut-costs-to-the-bone engineering that USACE seems to specialize in. It's bad enough they are:

- cheaping out on a component they are already designing for elsewhere (another paragraph on the same page as the passage above calls for the inlet channel to allow water flow velocities suitable for FSI's),
- moving those FSI fabrication and installation costs to Option 2 to make their Option 1 budget look better,

But to top it all off, they are hamstringing the future operations of the lakefront stations - and adding risk to the citizens of the city - while Option 2 is under construction.

And in the final analysis, they are likely putting in a technically inferior pump inlet which causes more vortices and will shorten the life of the pumps in the long term.

Spare Capacity - not so much
And just to go back to the point about no spare capacity, because I don't want to bury a lede. The Corps has always, public statements notwithstanding, intended to do the bare minimum on these stations. Their constant delays, the lack of attention, and the raiding of funds all point to how low a priority the pump stations are on their scale. But to now have their skimping then place the citizens at risk in the future is inexcusable.

The Corps plans (apparently) on installing pumps with peak flowrates of:

17th Street: 12,500 cubic feet per second (cfs)
Orleans Avenue: 2700 cfs
London Avenue: 9000 cfs

The 17th Street flowrate is based on a current flow of 10,500 cfs and a long-planned 2000 cfs expansion by the Sewerage & Water Board. The London Avenue flowrate is based on a current flow of 8000 cfs and a future S&WB expansion of 1000 cfs. So while there might be spare pumps at 17th and London initially, when the S&WB goes to expand their stations on those canals, the spare capacity at the lakefront stations will disappear, because of decisions being made now.

The flowrate at Orleans is based on the current flow. Oddly, the Corps doesn't seem to be considering future expansions at Orleans, even though the Sewerage & Water Board is. So any capacity increase along Orleans Avenue will be completely foreclosed by the Corps' plans on that canal.

It is foolhardy not to design in spare pumps, but that is what the Corps is doing.

And one last point: now that we finally have in print exactly what the design flows are for the new stations, we can calculate the exact amount of extra property tax burden the City of New Orleans will incur. That's because the Corps will not be running these new stations, the Sewerage & Water Board will. And the Sewerage & Water Board gets its revenue for drainage operations from property tax millages.

The going rate for annual Operations and Maintenance of the S&WB drainage pumps is $500,000 per 1000 cfs of flow. The total proposed peak flow of all three lakefront stations is 24,200 cfs.

Thus the annual additional tax burden on New Orleans's propertyholders will be $12.1 million. Spread out over the theoretical 50 year lifespan of the stations, that is $605 million.

Along with so many other things, that is a true cost of Option 1 when compared to Option 2. That cost would not exist with Option 2, because Option 2 replaces the existing pumping stations, rather than simply duplicating them out at the lakefront.


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