Date Presented

Spring 5-2020

Document Type

Thesis

Degree Name

Bachelor of Science

Department

Environmental Science

First Advisor

Thomas Shahady, Ph.D.

Second Advisor

David Perault, Ph.D.

Third Advisor

Nancy Cowden, Ph.D.

Abstract

Dam removal in the United States is an increasingly common practice as dams built decades ago begin to experience structural issues or environmental changes necessitating this action. In Lynchburg, Virginia, College Lake, an 18 Ha reservoir, was briefly overtopped during strong storms during August 2018 causing minor damage to the dam. In response, the City of Lynchburg deemed it necessary to drain the lake to protect property owners downstream fearing complete dam failure. During assessment to determine the best practice for dam removal, College Lake remained drained for 12 weeks as debate to conclusively determine a best course of action occurred. This system has been extensively studied for 10 years prior to the overtopping prompting the current study of dam removal to aid the scientific community on the resulting environmental effects of dam removal. During the draining period of time (August –October 2018), I sampled the biological and physical components of river water quality downstream of the lake. Simultaneously, I assessed river water quality above the lake to compare to the changes downstream. I also sampled Ivy Creek, a tributary to Blackwater Creek unimpacted by the draining of the lake as a control. Through comparisons, the resulting trends suggested a high increase in downstream sediment likely due to the exposed lakebed of College Lake when compared to historical trends and control. Coupled concurrently with a decline in other measured water quality standards, I suggest the lake is a critical water quality improvement feature in this watershed. This indicates a strong need to understand the water quality function of reservoirs before future removal.

Download

Share

COinS