One only needs to study the soil and geologic history and location of the ancient Mississippi and Ohio Rivers to understand why Len Small levee if patched will continue to fail. Much of Dogtooth Bend located in Alexander County, Illinois was originally in the ancient Ohio River valley (Figure 1) alluvial sediments north and east of the confluence with the ancient Mississippi River. The ancient Ohio River valley soils underlain by alluvial sediments and have been easily eroded by the re-aligning modern Mississippi River which now travels through the bedrock controlled Thebes Gap (Figure 2) and into the Ancient Ohio river valley. The primary objectives of this paper are: 1) to explain why Len Small levee, Alexander County, Illinois, US will continue to breach during major flooding events if repaired and 2) to develop a new combined raised causeway and levee system which will provide a Mississippi River floodwater bypass, be sustainable, encourage and fund a land use change, restore the degraded highway road beds, protect remaining Dogtooth Bend farmsteads and farmland that have not yet been degraded by past flooding events and provide floodwater storage during major flooding events at the confluence of the Mississippi and Ohio Rivers.
References
[1]
Olson, K.R. and Morton, L.W. (2016) Managing Mississippi and Ohio River Landscapes. Book division of the Soil and Water Conservation Society. Ankeny, Iowa.
[2]
Olson, K.R. and Morton, L.W. (2014) Dredging of the Fractured Bedrock-Lined Mississippi River Channel at Thebes, Illinois. Journal of Soil and Water Conservation, 69, 31A-35A. https://doi.org/10.2489/jswc.69.2.31A
[3]
Olson, K.R., Morton, L.W. and Speidel, D. (2016) Missouri Ozark Plateau Headwaters Diversion Engineering Feat. Journal of Soil and Water Conservation, 71, 13A-19A. https://doi.org/10.2489/jswc.71.1.13A
[4]
Pinter, N. and Heine, R.A. (2005) Hydrodynamic and Morpho-Dynamic Response to River Engineering Documented by Fixed Discharge Analysis. Lower Missouri River, USA. J. Hydrology, 302, 70-91. https://doi.org/10.1016/j.jhydrol.2004.06.039
[5]
Olson, K.R., Morton, L.W. and Speidel, D. (2016) Little River Drainage District conversion of Big Swamp to Fertile Agricultural Land. Journal of Soil and Water Conservation, 71, 37A-43A. https://doi.org/10.2489/jswc.71.2.37A
[6]
Olson, K.R. and Morton, L.W. (2014) The 2011 Ohio River flooding of the Cache River Valley in Southern Illinois. Journal of Soil and Water Conservation, 69, 5A-10A. https://doi.org/10.2489/jswc.69.1.5A
[7]
Morton, L.W. and Olson, K.R. (2019) Securing the Nation’s Infrastructure: The Ohio River. Journal of Soil and Water Conservation, 74, 5A-11A.
https://doi.org/10.2489/jswc.74.1.5A
[8]
Olson, K.R. and Morton, L.W. (2016) Mississippi River Threatens to Make Dogtooth Bend Peninsula in Illinois an Island. Journal of Soil and Water Conservation, 71, 142A-148A. https://doi.org/10.2489/jswc.71.6.140A
[9]
Olson, K.R. and Morton, L.W. (2017) Managing the upper Missouri River for Agriculture, Irrigation, Flood Control, and Energy. Journal of Soil and Water Conservation, 72, 105A-110A. https://doi.org/10.2489/jswc.72.5.105A
[10]
Olson, K.R. and Morton, L.W. (2013) Soil and Crop Damages as a Result of Levee Breaches on Ohio and Mississippi Rivers. Journal of Earth Science and Engineering, 3, 139-158.
[11]
Olson, K.R. and Morton, L.W. (2013) Impacts of 2011 Len Small Levee Breach on Private and Public Illinois Lands (July/August). Journal of Soil and Water Conservation, 68, 89A-95A. https://doi.org/10.2489/jswc.68.4.89A