Alyssa Bucci will have her thesis defense on May 14th at 2pm in ECSB 1202. Zoom link is available via invite. Please contact oesadmin@odu.edu.
Abstract title: Variability in Nutrient and Enterococcus Concentrations in Tidal Floodwater across Watersheds with Different Land Uses
Tidal flooding is an increasingly pressing hazard in coastal Virginia due to sea level rise and land subsidence. The Hampton Roads region of Virginia has the second-highest rate of relative sea level rise in the United States and experiences frequent tidal flooding, but the water quality impacts of this flooding on the Chesapeake Bay are not being accounted for. High concentrations of dissolved nutrients and Enterococcus bacteria (a fecal indicator) have been observed in tidal floodwater of the Lafayette River, a tributary of the James River and the lower Chesapeake Bay. This study investigates variability in dissolved nutrient and Enterococcus concentrations in tidal floodwater across watersheds with different land uses. Floodwaters in urban and rural watersheds in the Hampton Roads region were sampled through community science events in multiple floods over three years. Floodwater concentrations of dissolved nutrients and Enterococcus consistently exceeded baseline estuarine concentrations. Additionally, Enterococcus concentrations frequently exceeded the Environmental Protection Agency’s threshold for safe public use of recreational waters. Nutrient loading may be greater in urban watersheds than in rural watersheds, but more sampling is needed to confirm these results. This research demonstrates that tidal flooding is a source of nutrients to the Chesapeake Bay in multiple watersheds with different land uses. Additionally, high concentrations of fecal bacteria in tidal floodwater may present a risk to public health. These impacts must be considered in restoration planning and climate change response.