Lesson Outline
Lesson Media Objects
Deana Namuth-Covert
Professor, Director of Online Education and Outreach, The Ohio State University; Agronomy & Horticulture Adjunct Professor, University of Nebraska
dcovert2@unl.edu
Erosion
Case Study on a Local Level
Case Study 1 - Local: HOLMES LAKE, Lincoln, NE
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Map of sedimentation depths at Holmes Lake, Lincoln, NE. Image by Olsson Associates
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The following case study demonstrates the secondary effect of soil erosion on surface water bodies. The case demonstrates how soil eroded from land makes its way to recreational lakes affecting the lakes storage capacity and aesthetic quality.
Holmes Lake is located in a 5.2 square mile watershed in Lancaster County, NE. Current use of watershed land is 80% to 90% residential and commercial. Since 1962, the bottom of the lake has risen eight feet and the lake has lost greater than 25% of its volume due to sedimentation. Increased lake sedimentation reduces the aesthetic appearance of the lake for recreation purposes, decreases aquatic and wildlife habitats, and most importantly it significantly reduces the lake’s ability to receive runoff from the watershed and control floods.
Much of the sediment that entered Holmes Lake came from development of land into residential and commercial housing.
Dredging and transporting 300,000m3 of sediment to an area near the lake will cost approximately 2 to 3 million dollars. These photos show a part of the Holmes Lake restoration project that began in 2003. (Source: Lincoln City Planner, 2003, personal communication)
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![](../Image/siteImages/Erosion-3.jpg) |
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Urban soil erosion. Rain water erodes exposed soil from construction sites. Image by R. Sutton |
Aerial view of Holmes Lake. Image by Olsson Associates |
Dredging removes several feet of sediment that was carried in from water erosion. Image by Olsson Associates |
![](../Image/siteImages/Holmes-Lake-Re-Done-SM.jpg) |
Restored Holmes Lake July 2005 Image by M. Mamo |
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Thinking Question:
Without restoration and dredging, what do you think will happen to Holmes Lake in Lincoln, NE in 10 to 15 years?
What to do...
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Develop model plans the city of Lincoln can take to prevent future damage to Holmes Lake.
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Develop model plans developers can take to prevent future damage to Holmes Lake.
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Develop model plans homeowners and businesses can take to reduce future damage to Holmes Lake.
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