The disastrous Flood of 1927 served as the catalyst for the construction of four strategically located reservoirs located in North Mississippi. With the Flood Control Act of 1928, the U.S. Army Corps of Engineers - Vicksburg District became involved in a comprehensive flood control program. The major components of the program included the construction of lakes, levees, and large concrete floodwalls. In 1936, the Yazoo Headwater Project became a reality and resulted in the construction of Sardis, Arkabutla, Enid, and Grenada dams.
Construction on Grenada Dam began in 1947 and opened for operation in January, 1954. Grenada Dam is located northeast of the City of Grenada on the Yalobusha River. The earthen-filled dam stands 80 feet above the streambed and measures 13,900 feet in length. It features a 200-foot concrete spillway with a crest elevation of 231.0 NGVD. Grenada Lake has overflowed the spillway four times since the dam was constructed occurring in 1973, 1980, 1983, and in 1991 when over 6 feet of water topped this structure. The intake structure contains 3 gates that measure 7.5 feet by 14 feet. Grenada Lake is Y-shaped and when filled to spillway crest extends up the Yalobusha River Valley a distance of 22 miles and up the Skuna River Valley a distance of 19 miles.
Until 1927, the U.S. Army Corps of Engineers had pursued a flood-control strategy of “levees only” for the Mississippi and other U.S. rivers. This strategy entailed constructing mammoth embankments to separate the river channels from the flood plains. Following rains of biblical proportions during the winter of 1926, the Mississippi River began rising and by New Year's Day 1927, it exceeded flood stage in Cairo, Illinois. Rains continued into the spring and on Good Friday, April 15, 1927, Greenville, Mississippi received 8.12 inches of rain. Communities along the Mississippi River received anywhere from 6 to 15 inches of rainfall. The Memphis Commercial Appeal warned: “The roaring Mississippi River, bank and levee full from St. Louis to New Orleans, is believed to be on its mightiest rampage…All along the Mississippi considerable fear is felt over the prospect for the greatest flood in history.” By April 16th the Mississippi River was carrying 3 million cubic feet of water a second—an unprecedented volume. Finally the inevitable happened...at 8:00 a.m. on April 21, 1927, 12 miles up river from Greenville at Mounds Landing, the levee burst with a force greater than Niagara Falls. The flood shattered levees from Illinois to the Gulf of Mexico inundating 27,000 square miles of land. (This was an area equal to the combined size of Massachusetts, Connecticut, New Hampshire, and Vermont.) As a result of the monumental rainfall amounts, the Mississippi River Valley saw more flooding, more damage, more fear, more panic, more misery, and more death by drowning than any American had seen before and hopefully will ever see again. Over 130,000 homes were lost, 700,000 people were displaced, 246 flood-related deaths were reported, and 350million dollars in property damage - an amount equivalent to approximately 5 billion dollars today. Because of this unprecedented disaster, Congress enacted the Flood Control Act of 1928. The U.S. Army Corps of Engineers was again charged with taming the Mississippi River. A comprehensive flood-control plan encompassing levees, locks, dams, and reservoirs has been implemented in an effort to control flooding in the Mississippi River Valley.
To log this cache, you will have to complete a few requirements. All requirements must be done with in 3 days of logging or it will be deleted.
1) At cache coords, what is the level of the water coming out at dam?
2) At waypoint #2, if water level was the 6th # from the top, how high would the water level be?
3) Calculate the flow rate in "Feet Per Second" at waypoint #3 location. This may be done by measuring a distance along the bank, floating an object from your starting point to the ending point, and recording the time it takes the object to float the distance. Once the "Distance" and "Time" are determined, calculate the "Feet Per Second".
4) Optional: Take a picture of yourself or your geocaching group with the dam in the background and attach photo to your log.
