Publications

How-to information for local governments on six land use management techniques that can be used to achieve community goals, preserve local natural resources, and protect the Chesapeake Bay.

This Work Plan is a key initiative of Federal agencies and the U.S. Corps of Engineers. It establishes interstate ecosystem management concepts and the establishment of the Anacostia as a National Urban Watershed Restoration Model.

Evaluation of ambient toxicity to living resources during late summer/early fall of 1997 in the Elizabeth River (4 stations) and South River (4 stations).

Represents a regional cooperative effort to gather all available information and assimilate best possible understanding of catfish biology, ecology and stock dynamics of native and introduced catfish species in the Chesapeake Bay system.

Appendices July 1990-December 1991. This is an archived document.

This work contains the following themes as they relate to the Chesapeake Bay: Watersheds, The Bay as a Source of Recreation and Renewal, Environmental Stewardship and Sustainability of the Bay/Stewardship

Land use activities in the Chesapeake Bay watershed are diverse and contribute significantly to water quality. Because of the long history of coal mining in the upper reaches of the Chesapeake Bay watershed, much concern has been generated regarding the impact of acid drainage from active and abandoned coal mines. The U.S. Environmental Protection Agency has singled out acid drainage from abandoned coal mines as the number one water quality problem in Appalachia. Acid mine drainage from abandoned coal mines is the most severe and extensive water pollution problem in western Maryland, West Virginia, and northern, central and western Pennsylvania. Within the Chesapeake Bay Basin, drainage from abandoned coals mines poses a significant threat to water quality in the Susquehanna. West Branch Susquehanna, and Juniata River basins in Pennsylvania, as well as North Branch Potomac River and its tributaries in West Virginia and Maryland.

Designed to evaluate ambient toxicity in the Chesapeake Bay watershed using a battery of water column and sediment toxicity tests. Toxicity of ambient estuarine water and sediment was evaluated during the fall of 1994 at six stations in Baltimore Harbor (Patapsco River) and two stations each in the Sassafras, Magothy and Severn Rivers.

This is a report.

The objective of this study was to determine the influence of a range of salinities (5, 15 and 25 ppt) on the acute toxicity of total dissolved and free cadmium to sheepshead minnow, Cyprinodon variegatus larvae and the copepod, Eurytemora affinis nauplii. Data were analyzed to determine if the acute toxicity (96 h LC 50s) was different among salinities for the test species. Total dissolved cadmium was measured in selected test conditions and the proportion of total cadmium as Cd+2 (free ion or toxic form) was determined at each salinity. Ninety-six hour LC50 values for C. variegatus were 180.3, 312.4 and 495.5 ug/L total cadmium at 5, 15 and 25 ppt, respectively. A significant increase in LC50 values with salinity was likely related to a decrease in the free ion as salinity increased. Ninety-six hour LC50 values for E. affinis were 51.6, 213.2 and 82.9 ug/L total cadmium at 5, 15 and 25 ppt, respectively. A comparison of LC50 values for this copepod between salinities showed a significant difference between 5 and 15 ppt and between 15 and 25 ppt. There was no difference in LC50 between 5 and 25 ppt. The physiological characteristics of E. affinis were likely responsible for the higher tolerance at the middle salinity. Cadmium speciation in the various test salinities was dominated by association with inorganic binding ligands; organic complexation was negligible. The speciation at all salinities was dominated by CdCl+ and CdCl2. The free ion accounted for 20, 8 and 4.5% of the total cadmium at 5, 15 and 25 ppt, respectively. As current water quality criteria do not distinguish among individual cadmium species these data have important implications for estuaries such as the Chesapeake Bay because the presence of the toxic form of cadmium will increase as salinity decreases.