• How many rivers and streams are in the Chesapeake Bay region?

    Altogether, more than 100,000 streams, creeks and rivers thread through the Chesapeake Bay watershed.

  • What is the difference between a tidal river and a non-tidal river?

    A tidal river is a river or a stretch of river whose flow and level are influenced by tides. For example, the Choptank, Potomac and Patuxent rivers have tidal and non-tidal portions.

  • What pollutes rivers and streams?

    Litter, nutrients, sediment and chemical contaminants are some of the common pollutants found in rivers and streams.

  • How do dams affect rivers and streams?

    Dams can block American shad and other migratory fish from reaching their upstream spawning grounds. Dams can also affect the natural flow of rivers and streams.

  • What is fish passage?

    Fish passage is the ability of fish to migrate up rivers, streams and other waterways, often to access spawning or rearing ground. Barriers to fish passage (which include road culverts, dams, dikes and other obstructions) can reduce the distribution and habitat available to American shad and other migratory fish and, in some cases, eliminate fish populations altogether.

  • How do fish passageways work?

    Fish passageways allow American shad and other migratory fish to pass over dams and reach their upstream spawning grounds. There are five major fish passageway designs used in the Chesapeake Bay watershed: denil, steeppass, vertical slot, pool and weir, and fish lifts.

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  • Amphibian

    A cold-blooded vertebrate that lives in water and on land. Amphibians’ aquatic, gill-breathing larval stage is typically followed by a terrestrial, lung-breathing adult stage. For example, frogs, toads and salamanders are amphibians found in the Chesapeake Bay watershed.

  • Anadromous fish

    Fish that spend their adult lives in salt water but must migrate to freshwater tributaries to spawn. For example, Atlantic sturgeon and American shad are both anadromous fish.

  • Benthic

    Bottom-dwelling. Benthic organisms spend at least part of their lives in, on or near the bottom of aquatic environments.

  • Chemical contaminants

    Pesticides, pharmaceuticals, metals and other toxic substances that can harm the health of both humans and wildlife.

  • Crustaceans

    Aquatic arthropods (invertebrates) that have gills, joined legs and exterior skeletons. Crabs, shrimps, barnacles, amphipods and isopods are all crustaceans.

  • Dam

    Any barrier which impounds or diverts water.

  • Nutrients

    Chemicals that plants and animals need to grow and survive but, in excess amounts, can harm aquatic environments. Elevated levels of the nutrients nitrogen and phosphorous are the main cause of poor water quality in the Chesapeake Bay.

  • Pollution

    The introduction of harmful substances or products into the environment.

  • Reservoir

    A natural or artificial place where water is collected or stored for use, especially water for supplying a community, irrigating land and furnishing power.

  • Sediment

    Loose particles of sand, silt and clay that settle on the bottom of rivers, lakes, estuaries and oceans. Suspended sediment pushed into the water by erosion is one of the biggest impairments to water quality in the Chesapeake Bay.

  • Tributary

    A creek, stream or river that flows into a larger body of water. For example, the Susquehanna, Potomac and James rivers are tributaries of the Chesapeake Bay.

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