Hundreds of thousands of creeks, streams and rivers thread through the Chesapeake Bay region. These tributaries send fresh water into the Bay, offer vital habitat to aquatic plants and animals and provide people with public access points where they can fish, boat and swim. While pollution and the installation of dams, culverts and other structures can affect the health of rivers and streams, local cleanups and reductions in polluted runoff can conserve their health.
Why are rivers and streams important?
Each day, the region's rivers and streams send about 51 billion gallons of fresh water into the Chesapeake Bay. Almost 90 percent of this fresh water comes from just five of these tributaries: the Susquehanna, Potomac, Rappahannock, York and James. These rivers are home to a diverse population of invertebrates, amphibians, fish and other critters:
- A number of aquatic plants can be found in freshwater tributaries, including algae, mosses and several species of underwater grasses.
- Diverse communities of benthic organisms can be found on the bottom of rivers and streams. These organisms—which include bacteria, clams, crustaceans, insect larvae and worms—form an important link in the food web, and act as an indicator of watershed health.
- Some fish can only be found in freshwater tributaries, including bass, catfish and sunfish.
- Anadromous fish—which include American shad and Atlantic menhaden—spend their adult lives in the ocean but migrate into freshwater rivers and streams to spawn.
- Frogs, turtles and salamanders can be found in freshwater tributaries during some parts of their lives.
Rivers and streams also provide people with much-needed public access points where they can fish, boat and swim, observe wildlife, and reconnect with the watershed. Building personal connections with the environment can benefit public health and conservation and stewardship efforts.
What factors affect river and stream health?
Litter and debris, nutrient and sediment pollution, chemical contaminants, and the installation of dams, culverts and other structures can affect the health of rivers and streams.
Litter and debris
Aquatic litter and debris includes plastic bags, cigarette butts, beverage bottles and other waste that enters the marine environment. Sometimes, this waste is thrown onto a street or into a waterway on purpose; other times, it enters the environment accidentally. In urban and suburban areas, waste that is on a street or sidewalk can be pushed into storm drains, rivers and streams when it rains. Aquatic litter can detract from an area’s beauty, smother grass beds and bottom-dwelling organisms, add chemical contaminants to the water, or be ingested by animals.
Nutrients and sediment
Excess nutrients enter the water through agricultural and urban runoff, vehicle emissions and other sources. These nutrients can fuel the growth of harmful algae blooms, which block sunlight from reaching underwater grasses and lead to low-oxygen dead zones that suffocate marine life.
Excess sediment enters the water through agricultural and urban runoff, stream bank and shoreline erosion, and other sources. Suspended sediment can block sunlight from reaching underwater grasses, smother oysters and other bottom-dwelling species, and clog ports and channels.
Almost three-quarters of the Chesapeake Bay’s tidal waters are considered impaired by chemical contaminants. These contaminants include pesticides, pharmaceuticals, metals and other substances that can harm the health of both humans and wildlife. These contaminants enter rivers and streams through air pollution, agricultural and urban runoff, and wastewater.
Dams and culverts
Dams, culverts and other structures can alter the flow of rivers and streams, accelerate the accumulation of sediment and block migratory fish from reaching their spawning ground. In some areas, dams are being removed or lifts, ladders and passageways are being installed to reopen river habitat and allow fish to swim upstream.
To conserve the health of rivers and streams, consider reducing the amount of pollution that can run off of your property. Install a green roof, rain garden or rain barrel to capture and absorb rainfall; use porous surfaces like gravel or pavers in place of asphalt or concrete; and redirect home downspouts onto grass or gravel rather than paved driveways or sidewalks. Follow safe and legal disposal methods of paint, motor oil and other chemicals to make sure they do not run into rivers and streams.