Event Title
Low-Head Dam Removal Causes Immediate Physical Habitat and Water Chemistry Degradation
Presentation Type
Poster/Portfolio
Presenter Major(s)
Biology
Mentor Information
Eric Snyder, snydeeri@gvsu.edu
Department
Biology
Location
Kirkhof Center KC18
Start Date
13-4-2011 2:00 PM
End Date
13-4-2011 3:00 PM
Keywords
Environment, Life Science
Abstract
This two year study focused on understanding the effects of the removal of the low head Nashville dam on the Thornapple River in Barry County, MI. A comparison of data taken from pre- to post-dam-removal indicated changes to the physical habitat, as well as water chemistry. In the reach directly below the dam there was an increase in fine sediment that accounted for an average cross-sectional channel aggradation of 26cm, from pre- to post-dam conditions. Nutrient limiting conditions also changed from pre- and post-dam-removal. Pre-dam-removal nutrient levels showed above-dam-sites to be phosphorus-limiting, and the sites below the dam to be nitrogen limiting. This changed after the dam was removed, when all of the sites appeared to be phosphorus-limiting. The most drastic nutrient limiting change occurred directly above the former dam, in which the N/P ratio was 22.00 before the removal of the dam, and then was found to be 7.90 after the removal of the dam.
Low-Head Dam Removal Causes Immediate Physical Habitat and Water Chemistry Degradation
Kirkhof Center KC18
This two year study focused on understanding the effects of the removal of the low head Nashville dam on the Thornapple River in Barry County, MI. A comparison of data taken from pre- to post-dam-removal indicated changes to the physical habitat, as well as water chemistry. In the reach directly below the dam there was an increase in fine sediment that accounted for an average cross-sectional channel aggradation of 26cm, from pre- to post-dam conditions. Nutrient limiting conditions also changed from pre- and post-dam-removal. Pre-dam-removal nutrient levels showed above-dam-sites to be phosphorus-limiting, and the sites below the dam to be nitrogen limiting. This changed after the dam was removed, when all of the sites appeared to be phosphorus-limiting. The most drastic nutrient limiting change occurred directly above the former dam, in which the N/P ratio was 22.00 before the removal of the dam, and then was found to be 7.90 after the removal of the dam.