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Elk River Basin - Physical Features
Streams/Watershed Areas
| Land Use/Cover  Streams
and Watershed Areas --
Streams flow in a network and grow in size and capacity from their headwaters until they flow into
another stream or river. Hydrologists
characterize stream size by assigning them an ‘order’.
For instance, a first order stream has no streams
that drain into it. When two first order
streams flow into one another, a second order stream is created.
Similarly, when two second order streams flow into
one another, a third order stream is created, and so forth.
What is a watershed? A watershed is any area of land on which rain falls and drains into a river system. Each river has its own watershed. The land area making a watershed is bound on each side by a divide. On the other side of the divide, the water flows towards another river system. The Elk River begins near Pineville, Missouri, where Big Sugar Creek and Little Sugar Creek converge. The Elk River flows into the impounded Grand Lake O’ The Cherokees in Oklahoma. The entire basin is 1,032 square miles, 866 of which lie within the state of Missouri. Eight sub-basins comprise the Elk River Basin, and are listed below.
Land Use/Cover -- The quality of the water that drains through a watershed is affected by the type of physical features within the watershed. One measure of physical features land cover. Land cover is measured by looking at aerial photographs and calculating area of forest, grassland, agriculture, and urban area that can be seen on the photograph. Land use/land cover within the Elk River Watershed consists of 50% forest and 50% pasture. Historically, land cover was 60% forest, 5% prairie, and 35% woodlands, glades, and savannas. Today, however, much of the land has been converted for use as pasture for free-ranging cattle and concentrated animal feeding operations Geology/Physiographic Regions -- The Elk River Basin lies completely within The Ozark Plateaus physiographic region. The basin lies on the Springfield plateau within the larger Ozark Dome structure. A dome is a geologic structure that is high in the center, surrounded by layers of rock sloping away from its center. The Ozark Dome was created over 500 million years ago when volcanic activity in the southwest corner of the state created the St. Francois Mountains. These mountains are the highest point of the Ozark Dome. When this uplift was occurring, there was also a shallow sea covering the area surrounding the St. Francois Mountains, including the area we now know as the James River Basin. As the sea rose and receded, it left behind layers of sediment that eventually became rock over many years. This is what is termed ‘sedimentary rock’. These rock layers are higher in elevation nearer to the St. Francois uplift, forming the Springfield and Salem plateaus. Since the rock is now exposed, weathering processes have eroded away the top layers, making the older layers more visible. Elk River Basin is predominantly of limestone, shale, and sandstone. Limestone is very soluble, and can dissolve fairly easily when in contact with water/rain. This results in sinkholes, caves, and springs. Several such areas are found within the Elk River Basin, particularly in the northern section and from Noel, Missouri, south into Arkansas. Soils -- Many different types of soils are found in the Elk River Basin. Soil type affects the amount of runoff reaching streams and the amount of suspended sediment carried into streams. The Elk River Basin is characterized by relatively good quality soils. Read more about area soils at http://www.conservation.mo.gov/fish/watershed/elk/geology/010getxt.htm Miscellaneous geology: See what else was happening when the Ozark Dome was being formed!
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Elk River | James River | Sac River | Spring River | North Fork Salt River |
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Missouri Watershed Information Network (MoWIN) |
Page last updated August 26, 2008 |
