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This was my presentation given at GIS in the Rockies 2010 on monitoring the levees of Sacramento. I cover some history of the levees and flooding and talk about what's been done and the GIS side of the monitoring.
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Monitoring the Levees of the Sacramento Valley Basin
City of Sacramento
Los Angeles
San FranciscoSan Joaquin Basin
Sacramento River Basin
City of Sacramento
Historical Timeline
•1848: Gold rush, Sacramento established
•1850: First major flood hits Sacramento
•1861: Largest flood in California history
•1860s: Failed “Swampland Districts” experiment and massive hydraulic mining
Historical Timeline•1870s: Levee building begins
•1890s: Federal involvement
•1940s: 90% of current system complete
Yuba City - 1955
1986 Flooding
“My question – and I ask this without ever having seen Pacific Storm Bob or whatever it’s called – [is] why do we have three days of front page stories and TV news stories about a rainstorm? Is it because Californians are sissies?”
- San Francisco columnist
1986 Flooding
In response, after the storm:
“Nature in California is a smiling killer that can turn on you at any time.”
- Carl Nolte (SF colleague)
1986 Flooding
Tyler Island
1986 Flooding
1986 Flooding
“Afterwards, if one were to take statistical probability as a guide, there was every reason to believe we would not see another flood of that magnitude for many years…”
- David Kennedy, former Director of CA DWR
(quoted from his forward to Battling the Inland Sea)
Arboga
1997 Flooding
Arboga
1997 Flooding
1997 Flooding
Olivehurst
“And yet, only eleven years later, the January 1997 flood produced flows on several major streams , such as the Feather and Yuba rivers, some 20 percent greater than 1986.”
- David Kennedy, former Director of CA DWR
(quoted from his forward to Battling the Inland Sea)
Impact of 1997 Flooding
1. Annual erosion inventory (USACE Sac District)2. Hydrographic Survey of System & Hydraulic Modeling3. Emergency fixes and maintenance efforts4. Repair work (limited to only 5 sites!)
June 3, 2004
Jones Tract (Delta)
August 29, 2005
August 29, 2005
January, 2006
LEVEES FINAL GRADE: D
January, 2006
February, 2006
A State of Emergency is declared for the Central Valley levees and emergency repairs proceed.
2009 Tasks for USACE
•Annual Erosion Inventory
•Paper to digital (Trimble GeoXT/XH)
•Erosion Sites File Geodatabase (GDB)
•SDSFIE Conversion
•Terrasync or ArcPad?
•Update Atlas and Site Rankings
ArcPad or Terrasync?
•USACE heavily leaned towards Terrasync
•Why? ArcPad 6-7 weaknesses•Buggy•Small viewing window cluttered by toolbars•Form builder difficult to use•Not as intuitive as Terrasync
•Known issue with Terrasync: How would it work with a GDB?
•What about ArcPad 8?
Terrasync Form Development
ArcPad 6/7 to ArcPad 8
ArcPad Form Development
The Winner: ArcPad 8
Upper Bank
Middle Bank
Lower BankToe
Underwater
Observed Attributes
Bank Slope/Berm Width
Erosion Location
Example: Soils
Example: Tree Hazard
Example: Vegetation
Current Status?
•The system is still heavily vulnerable!
•Over 70 sites repaired since 2006!
•Multiple agencies working together!
•10,000 linear feet (at least) of levee being repaired every year.
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