Efforts To Control Flooding 1851 To Present Levees and Warnings

Extensive floods in 1849 and 1850 (followed by an all-time record flood in 1858) led to action in Washington. Congress established the Delta Survey in 1851 to address the design and construction of works to control floods and to aid navigation on the Lower Mississippi River. The river's massive 1858 flood gave the survey team of army engineers a benchmark to work from. The Delta Survey team recommended a "levee-only" policy in 1861, a policy followed well into the twentieth century. The levee-only approach was to be done primarily to protect cities and communities along the river's main course. The U.S. Department of the Army was given the primary responsibility for addressing the problem, and its engineers launched a program to control flooding.

in 1871 Congress directed the secretary of the Army to establish a network of river-stage gages along the Mississippi and Ohio Rivers. The Weather Service, established in 1870 as an arm of the Army's Signal Service, formed in 1873 a River and Flood Service, which began collecting the stream-level values and rainfall amounts (by telegraph) to make flood warnings, issued in Washington and transmitted by telegraph to district offices. These were issued for major flooding developing in the Lower Mississippi River basin, which was then the most flood-prone pan of the entire Mississippi basin (Morrill, 1897). Flood prediction remained an ever-improving art based on empirical relationships of past rainfall conditions and river stages until the 1950s, when the science of rainfall forecasting had advanced. Such advances had led to improvements in flood forecasting on the Mississippi and its headwaters.

Most federal attention to flood control in the nineteenth century went to the construction of levees along the Lower Mississippi, then an easily flooded alluvial valley. In 1879 Congress established the Mississippi River Commission to survey the entire river system and to develop plans for navigation and flood control on all main river channels, reflecting growing federal responsibility for control of flooding. By this time, privately funded flood damage reduction measures, and mainly levees of varying types, were being built along parts of the Mississippi River. (Fig. 2).

As the nineteenth century ended, a system of major levees was being erected along the Lower Mississippi without any ccntral planning or direction, and flooding continued there. Devastating floods in 1903 and 1912 led to ever more public

Figure 2 Refugees of the 1893 flood along the Lower Mississippi River. They Survived by living on one of the many dirt levees built during the 1866-1890 era. Unfortunately, this scene has been repeated several times during the twentieth century.

pressure for government action against floods. Congress passed a Flood Control Act in 1917, calling for levee construction based on cost sharing with local districts, one of the first government-private sector partnerships.

Levees continued to be built in the basin, and in 1927 the Mississippi River Commission proudly announced that the levee system of the Lower Mississippi was ready to withstand the worst of floods. Two months later nature refuted their claim. An enormous spring flood developed on the Ohio River and spread into the Lower Mississippi River basin. It overwhelmed the massive levee system built during 1870 to 1926. The flood killed 246 persons and drove 600,000 from their homes as it spread over a 200-km wide swath extending from Cairo, Illinois, southward for 1500 km (Keating, 1971), covering large parts of Kentucky, Tennessee, Mississippi, Arkansas, and Louisiana.

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