What are Point and Nonpoint Sources?

Point Source Pollution is when sources of pollution come to the river at one point. Nonpoint Source Pollution is when sources of pollution have resulted in the disturbance of the earth or contamination of the surrounding land.

Point Sources:

Point Sources account for over 60% of the water pollution in the U.S. today.


Industry plays a major role in point source pollution. Industrial wasterwater and discharges include oils, greases, metals, chemicals, such as PCB's and pesticides, and debris that eventually head into the Cuyahoga River.

Oil Spills and Grease:

Oil spills and dumping also play a major role in point source pollution. Spilled grease, oil, and other hazardous substances from overturned trucks and leaking cars have a major impact by eventually running into rivers and sewers. Also, the disposal of used motor oil and grease affects the water by going into a storm sewer which can overflow into the river, or it will go directly into the river.

Other Point Sources:

Also affecting the water are outflow pipes from industries, companies, and other such buildings directly pouring their waste into the rivers and lakes. Thermal pollution decreases the waterÕs ability to hold oxygen.

Nonpoint Sources:

Nonpoint pollution occurs when the source of pollution can not be easily pinpointed.


The Cuyahoga River serves as a dump for wastes. Wastes, often being dumped with no permit include debris, raw sewage, public and private litter, natural debris, oils, scums, paints, chlorides, PAHÕs, organic carbon, metals (cadmium, chromium, iron, cyanide, lead, zinc, copper, and nickel), toxins from industries and home use, organic pollution (grass, leaves, human sewage, pet wastes, and dead organisms), and inorganic pollution (suspended and dissolved solids).

Bacteria levels increase in the Cuyahoga River following heavy rainfalls because of wastes upstream.


Sediment in the Cuyahoga River can be destructive. Sediments come from highly traveled, unvegetated, open space, abused stream banks, modification of streams and wetlands, other water bodies, high-till farming that make soil erode, decomposing material, and dredging for large ships to travel.

This sediment is posed as a problem because it destroys the aquatic habitat through the removal of riparian vegetation and alteration of a stream's natural hydrology. Some particles do not sink and cause a muddy appearance. There are also contaminated sediment particles that fish come in contact with.


Runoff is referred to as any liquid substance that runs from one area to another and is not absorbed by the ground.

Urban runoff from buildings and streets include oil, grease, trash, road salts, lawn fertilizer, lead, metals, bacteria, and PCB's that run into surface and ground waters.

Agricultural storm water runoff from rain and snow melt carries animal wastes, pesticides, nutrients, and sediments into surface and ground waters.

Other storm water runoff contributors are logging, timber cutting operations, and construction sites.


Another nonpoint source of pollution is leakage. Abandoned surface mines and waste piles may leak sediments, acids, and chemicals. Improper disposal of waste directly into or above an aquifer can cause serious ground water contamination.


Combined sewer overflows which consist of storm water and untreated sewage and sanitary sewer overflows are a problem when they overflow into lakes and rivers. They put trash, sewage, bacteria, wastes, and other pollutants into the water.

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