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Welcome Rob Rash CEO/Chief Engineer St. Francis Levee District of Arkansas.
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WelcomeRob Rash CEO/Chief EngineerSt. Francis Levee Districtof Arkansas
WARNING! This area is shown as being protected from the 1-percent-annual-chance flood hazard by levee, dike, or other structure. Overtopping or failure of this structure is possible, which could result in destructive flood elevations and high velocity floodwaters. There is a chance that large floods will occur that are greater than the level of protection provided by the levee. Communities should issue evacuation plans and encourage property owners behind these structures to purchase flood insurance even if the structure is currently shown as providing protection for the 1-percent-annual-chance flood.
Mississippi River Basin • 41% of the Continental United States • Drainage from Colorado (West) and New York (East) • Ohio River contributes 68% and Mississippi River contributes 32%.
1928 Flood Control Act • Government became involved • 1928 Flood Control Act • Authorized Mississippi River & Tributaries Project (MR&T) • Improved existing Levees • Levee District Sponsored, Operated & Maintained
1928 Flood Control Act • “The flood used in the design of this plan is that predicted by the Weather Bureau as the “maximum possible” and by the Mississippi River Commission as the “maximum probable.” The stages predicted by these two bodies were practically the same. When there was a difference the higher stage was used. This resulted in a project flood with stages, if confined, of 66 feet at Cairo. The Weather Bureau obtained its “maximum possible” flood at Cairo by using the maximum Ohio flood with “the Mississippi, Cumberland, and Tennessee Rivers contributing their tides at just the proper time to insure the greatest effect at Cairo, an improbable occurrence it is admitted but nevertheless a remotely possible one.” The predicted stage at Arkansas City, 74 feet, is the result of the above stage at Cairo and the Arkansas and White at their maximum predicted stage. Below the Red the same flood reduced by river channel reservoir capacity and with flow from the Yazoo and Red added gives the project flood, which is taken as 3,000,000 second-feet.”
Changes to 1928 FC Act • Mississippi River Levees modified after 1937 & 1950 floods • Current Project Design based on modifications for 1973 flood • Numerous Flood Control reservoirs have been constructed on the Ohio, Missouri, Cumberland, Tennessee and numerous other Tributaries to the Mississippi River
Pecan Point Seepage Control Project • Includes Installation of 100 Relief Wells. • Project completed in October 2005.
Lime/Fly-Ash Injection Goal: Lime/Fly-Ash Slurry fills voids and reacts with Clay minerals 5’ Center Spacing (Primary & Secondary) 10-15’ Deep Injection Depths Mix – 1 part lime / 3 parts fly-ash 6-8 lbs of mix / gallon water Primary Injection – 1 lb/ft3 Secondary Injection – 0.5 lb/ft3
Slope Flattening 5’ Failure Surface Flattened Slope (1V on 4.5 H) 1 Original Slope 1.5 Excavation Line • ProcedureAdvantagesDisadvantages • Excavate Existing Material 1. Low Cost 1. Borrow Required • Locate Additional Borrow 2. Permanent fix 2. ROW Issues • Mix new material with existing 3. Environmental Issues • Construct to Stable Slope 4. Potential for Bad Borrow
Tree/Woody Growth LANDSIDE RIVERSIDE BLOCKS EMERGENCY ACCESS UNCONTROLLED PIPING THROUGH AND ALONG ROOT CAVITIES
In Summary • MR&T Project extends from Cape Girardeau, MO to the Gulf of Mexico • Protects 35,000 square miles • 15 Million People • Authorized in 1928 Flood Control Act • 15.0 Billion dollars of Federal Investments and untold Billions of dollars in local investments over 150 years
In Summary • “Recommendation” to purchase flood insurance is taken by the Bankers and Mortgage Lenders as a regulation • FEMA actions will create an economic disaster for both businesses and individuals • Negate Billions of dollars spent federally and locally to protect the most productive and fasting growing area in the country