🚀 go-pugleaf

In message <Cxw7EB.3JM@odin.corp.sgi.com> Michael K. Poimboeuf writes:
>The proposed dam wouldn't somehow move Sacramento out of the flood 
>plain. Not unless the CORPs perfected hydro-powered teleportation. :-)
>The flood plain that the dam is primarily aimed at protecting is the 
>Natomas flood basin.
For those of you unfamiliar with the Sacramento area, Natomas is a 
suburb of Sacramento, north of the American River.  While it is true 
that much of Natomas is undeveloped, much of it is - with high density 
residential housing.  These people are in the 100-year flood plain, and 
a levee breach would put water up to their rooftops.  So, while much of 
the driving force behind a dam project is the development of Natomas, 
there is a genuine public safety component there also.
>This flood basin is not yet a fully developed 
>part of Sacramento, but rather, an area that developers want to continue 
>build on.  It's the developers that want to build this dam. The 
>developers stand to gain Billions in windfall profits if they can develop 
>the flood-basin/wetland/swampland. It's one of the oldest stories of 
>California water politics played over yet again, except in this case they 
>want to build on the swamplands instead of the desert.
Yes, probably true.  But it is the announced intent of SAFCA (Sacramento 
Area Flood Control Authority) to get the Natomas area out of the flood 
plain, irrespective of the means.  Here the question is the level of 
protection.  If other means (levees, tinkering with Folsom, diversion 
to the south) are used to get Natomas out of the flood plain, the level 
of protection there is likely to protect for less than a 200-year 
return interval flood.  As the Mississippi/Missouri floods last year 
demonstrated pretty well, these very large (500-year) floods are not 
some hydrologist's wet dream.  They can really happen.  Saint Louis had 
a 200-year plus floodwall that came within 0.8 foot of overtopping.  
That's why a very high level of protection for urban areas is always 
desirable, but is not present at Natomas (or Sacramento for that 
matter).  Your basic dam can protect against these infrequent floods.

>How about those that currently recreate on the river that this dam 
>would bury under silt? How about those that own land that would be 
>condemed. How about the gold miners that would lose their livelyhood? 
>How about the loss of a fantastic stock of native Rainbow trout? How 
>about drowning an area that is just now begining to support Bear & 
>Mtn Lion populations again?
All true.  Does a dry dam (pool fills only during floods) engender the 
same objections? 

>And what about the fools who buy property that is "protected" by this 
>behemouth that are flooded out when the Sacramento River overflows its 
>levees, and the drainage system in Natomas plugs up?
Well, you've got other behemoths like Shasta and Oroville that are 
supposed to keep the Sacramento River from flooding.  The Natomas 
drainage system will plug up if it's not maintained.