As with all nature areas in Florida, there is the potential for venomous snakes and alligators to be present. Please use caution and be aware of your surroundings as you walk the trail here. DO NOT LEAVE THE TRAIL FOR ANY REASON!
A levee is a natural or artificially constructed ridge or wall along the edge of body of water that regulates water levels.
The main purpose of artificial levees is to prevent flooding of the adjoining countryside and to slow natural course changes in a waterway to provide reliable shipping lanes for maritime commerce over time; they also confine the flow of the river, resulting in higher and faster water flow. Levees can be mainly found along the sea, where dunes are not strong enough, along rivers for protection against high-floods, along lakes or along polders.
Levees can be permanent earthworks or emergency constructions (often of sandbags) built hastily in a flood emergency. When such an emergency bank is added on top of an existing levee it is known as a cradge.
Some of the earliest levees were constructed by the Indus Valley Civilization (in Pakistan and North India from circa 2600 BC) on which the agrarian life of the Harappan peoples depended. Levees were also constructed over 3,000 years ago in ancient Egypt, where a system of levees was built along the left bank of the River Nile for more than 600 miles (970 km), stretching from modern Aswan to the Nile Delta on the shores of the Mediterranean. The Mesopotamian civilizations and ancient China also built large levee systems.
Because a levee is only as strong as its weakest point, the height and standards of construction have to be consistent along its length. Some authorities have argued that this requires a strong governing authority to guide the work, and may have been a catalyst for the development of systems of governance in early civilizations. However, others point to evidence of large scale water-control earthen works such as canals and/or levees dating from before King Scorpion in Predynastic Egypt, during which governance was far less centralized.
Levees are usually built by piling earth on a cleared, level surface. Broad at the base, they taper to a level top, where temporary embankments or sandbags can be placed. Because flood discharge intensity increases in levees on both river banks, and because silt deposits raise the level of riverbeds, planning and auxiliary measures are vital. Sections are often set back from the river to form a wider channel, and flood valley basins are divided by multiple levees to prevent a single breach from flooding a large area.
Artificial levees require substantial engineering. Their surface must be protected from erosion, so they are planted with vegetation such as Bermuda grass in order to bind the earth together. On the land side of high levees, a low terrace of earth known as a banquette is usually added as another anti-erosion measure. On the river side, erosion from strong waves or currents presents an even greater threat to the integrity of the levee. The effects of erosion are countered by planting suitable vegetation or installing stones, boulders, weighted matting or concrete revetments. Separate ditches or drainage tiles are constructed to ensure that the foundation does not become waterlogged.
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1) What year did the levee and ditch construction begin here?
2) By 1968, most of nearby Paynes Prairie had already been drained. Why?
3) What year were ditches dug to drain the 1000 acres within the levee?
4) What was Levey Prairie used for from the early 1970s to the mid-1990s that would not have been possible if the levees and ditches had not been constructed?
5) After the restoration, what is the range of water depth within the marsh that is seen today?
6) List 3 of the benefits of the restoration listed on the sign?
7) Using information from the sign and by observing at the waypoint, what do you see at the waypoint and what do you think that structure's purpose is?
8) OPTIONAL: Post any pictures of your time in the preserve
References:
https://en.wikipedia.org/wiki/Levee