Kelly Shaw, '11

Kelly Shaw '11, a major in geology and minor in political science, is collecting baseline data on water quality at each of the dam sites in order to augment the data being logged continuously along the project reach.  The parameters she is measuring include nitrates, phosphates, chlorides, and hardness.  Kelly is using a Hach DREL/2010 Advanced Water Quality Laboratory and the DR/2010 Spectrophotometer for her analyses.  Downstream and changes in chemical quality will provide an indication of sources of pollutants.  For example, sources of nutrient enrichment in Beaver Creek may come from agricultural sources or rural septic systems, but changes downstream through Springfield may be a result of dilution or inputs from combined sewer overflows or residential applications of fertilzer.  As the dam modifications are made, Kelly's data will be used to assess the impact of dam removal on water quality.  For example, organics trapped in fine sediment behind dams consume oxygen, resulting in low dissolved oxygen content.  With dam removal, we expect to see dissolved oxygen levels increase.

Kelly is sampling 10 sites, including upstream and downstream of each of the four low-head dams as well as at the old International Harvester plant and the Snyder Park bridge. The latter two sites are being continuously monitored for temperature, specific conductivity, pH, oxidation-reduction potential, dissolved oxygen, and turbidity.  At each site a section of the stream was chosen for sample collection that would best represent the stream site overall. The sector was divided into four subsections where water samples are collected using a depth-integrating suspended sediment sampler. Subsamples are mixed and the final sample is pulled from the composite sample.

Kelly's data will be used to understand changes in water quality downstream and over time as the lowhead dams are removed.  By collecting data prior to and following dam removal, we will be able to understand human impacts on the stream and its nutrient load.  Using discharge data from the Plum Street gaging station and another station on Beaver Creek in conjunction with  U.S. Army Corps of Engineers releases from C.J Brown Reservoir, we will be able to determine total loads of pollutants like nutrients in Buck Creek and their change downstream.

Here is an example of one of the chemical tests for nutrients. The dark blue line is the stream level over the time and we can compare it to the data that I collected from each of the ten sites. The big rain event resulted in an increase in nitrate levels, but we want to know if the downstream changes in nitrate are a result of dilution or whether the downstream reaches act as a sink for nutrients like nitrate.

I(ron seems to be related to the rainfall events and the level of the stream. However, as with the other chemicals we want to determine if the iron concentration is being diluted as it moves downstream or if there are other variables that are creating the amount of iron found in my samples.