Water quality of the James River estuary
The James River estuary experiences significant water quality problems associated with bacteria and algal blooms.
The presence of harmful bacteria in the estuary is indicative of fecal contamination. These derive from natural sources (e.g., geese and other wildlife), urban runoff (e.g., dog waste) and municipal wastewater. Wastewater is discharged into the James River from treatment plants serving the Richmond metropolitan area. During rain events, the combination of rainwater runoff and wastewater may exceed plant capacity, resulting in the release of untreated wastewater and elevated levels of harmful bacteria in the James. For this reason, citizens are cautioned against swimming in the James following rain events. The City of Richmond has recently upgraded its wet weather treatment capacity to reduce sewer overflow events. Further steps are planned to reduce, capture and store stormwater runoff. VCU will continue its long-term monitoring (since 2010) to assess the occurrence of fecal bacteria in the James.
The James estuary experiences algal blooms in the area near the VCU Rice Rivers Center. Algal blooms are excessive growths of free-floating algae (phytoplankton) that occur during favorable conditions in summer. Excess algae can contribute to a number of water quality problems including reduced water clarity, low dissolved oxygen and the presence of algal toxins (chemical produced by algae that are harmful to humans and aquatic biota).
Dr. Paul Bukaveckas (Center for Environmental Studies) has been studying algal blooms in the James for over a decade. His results show that algal blooms occur in the tidal freshwater segment of the James due to shallow conditions, which enable the algae to capture more sunlight, and the presence of dissolved nutrients that come in part from treated wastewater. Some of these algae produce toxins, though monitoring work has shown that toxin levels in water and fish tissues do not pose a significant health threat.
Recent publications:
Factors Governing Light Attenuation in Upper Segments of the James and York Estuaries and Their Influence on Primary Producers
The Influence of Storm Events on Metabolism and Water Quality of Riverineand Estuarine Segments of the James, Mattaponi, and Pamunkey Rivers
Cyanobacteria and cyanotoxins at the river-estuarine transition
Dr. Paul Zimba has recently joined the research faculty of the Rice Rivers Center, and is an expert on algal taxonomy and toxins. He will be conducting studies of harmful algae in Lake Anna and the Shenandoah River. Dr. Zimba and research associate Ron Lopez are also pursuing research to document biotoxins produced by benthic, harmful algal mats in the Shenandoah River. This project will apply cutting-edge technologies, including UAVs and hyperspectral remote sensing, and adds new capabilities to VCU's HAB research.