Chesapeake Bay has long been recognized as a biologically rich ecosystem, one whose wide expanse of shallow estuarine waters is unique in the world. When the biological bounty of the Bay declined dramatically, federal, state, and local governments began restoration efforts on a mammoth scale. While the successes have been many, the lesson of the last few decades has been that this great estuary cannot be restored without addressing the multitude of human activities in the watershed that cumulatively distort its ecological processes and degrade its resources. Today governments, industry, and the public are focusing on three major restoration efforts: reducing nutrient inputs, reducing toxic pollutant loads, and restoring living resources. Recognizing that power generation is an important component of the activities affecting the Bay, the Maryland Department of Natural Resources (DNR) Power Plant Research Program (PPRP) is working in partnership with electric utilities to avoid, minimize, and mitigate adverse impacts on both local and regional scales. Historically, PPRP has participated in cooperative state and industry efforts at Conowingo Dam and other upstream dams on the Susquehanna River (the Bay's largest freshwater tributary) that have helped quantify impacts to migratory fish, resulting in modifications to dam operations and installation of fish lifts to restore populations of American shad and other anadromous fish. Other restoration projects include mitigation of acid mine drainage in the upper reaches of the watershed, installation of lime dosers in affected streams, investigation of the beneficial uses of coal combustion products for mine reclamation, and operation of a successful hatchery and release program. Currently, PPRP recognizes that its research efforts need to look up the watershed at cumulative effects on a regional scale. Recent research on the regional level undertaken by DNR includes a statewide biological stream survey to provide comprehensive baseline information on the health of freshwater systems in Maryland, and development of reference-based ecological indicators. These indicators are critical for assessing the effects of different degrading activities and measuring progress towards environmental goals. A related cumulative impact model, currently under development, will couple indicators of biological integrity with spatial data on land uses, power-related impacts, and other anthropogenic stressors to evaluate watershed impacts on aquatic systems. As part of model development, the role of vegetated riparian corridors is being evaluated to support watershed-wide initiatives to restore riparian forest buffers on Chesapeake Bay tributaries. These biological survey data and other information are being used to identify biodiversity hotspots in the State and construct maps of ecologically sensitive areas for the evaluation of cumulative effects and targeting of conservation and restoration priorities. (C) 1999 Elsevier Science B.V. All rights reserved.
