A Comparative Analysis of the Health of the Ni River and Massaponax Creek in Spotsylvania

A COMPARATIVE ANALYSIS OF THE HEALTH OF THE NI RIVER AND MASSAPONAX CREEK IN SPOTSYLVANIA COUNTY. Dr. M. L. Bass, E. E. Stewart, A. T. Elliott & H. E. Richters, University of Mary Washington. The main focus of this research project was to determine the health of both the Ni River and Massaponax Creek in Spotsylvania County, VA. The two streams provide a good demonstration of the effects of urban development. There are four sample sites located on Massaponax Creek and three sites on the Ni River. At each site, macrobenthic samples were taken as bio-indicators of pollution. These samples were corroborated by water chemistry analyses, including conductivity, dissolved oxygen levels, fecal coliform, alkalinity, calcium hardness, phosphate and nitrate concentrations and total dissolved solids. All samples were taken within each season. An examination of the macrobenthic results indicate that throughout the summer, the %EPT of the Ni River was approximately 90% at most sites. The low was of 82.8% at the McEwan Farm site. At Massaponax Creek, the summer's %EPT ranged from 97.3% at the Wetland to a low of 62.7% at Route 208. These ranges are caused by variations in water chemistry. During autumn and winter, the %EPT's steadily fell, as the organisms completed their aquatic life cycles. It can also be noted that one particular site on Massaponax was afflicted by a high CFU count, as well as high spikes in alkalinity, phosphate and hardness in the winter. It has been determined that the Ni River is healthier than Massaponax Creek. This is represented by the higher EPT percentages and diversity of macrobenthic individuals within the Ni River. However, Massaponax Creek has maintained good health despite increased development within its watershed.