Pollution of the Ocean by Plastic and Trash

Garbage has been discarded into the oceans for as long as humans have sailed the seven seas or lived on seashores or near waterways flowing into the sea. Since the 1940s, plastic use has increased dramatically, resulting in a huge quantity of nearly indestructible, lightweight material floating in the oceans and eventually deposited on beaches worldwide.

Pollution of the Ocean by Sewage, Nutrients, and Chemicals

Coastal waters receive a variety of land-based water pollutants, ranging from petroleum wastes to pesticides to excess sediments. Marine waters also receive wastes directly from offshore activities, such as ocean-based dumping (e.g., from ships and offshore oil and gas operations).

Pollution Sources: Point and Nonpoint

All activities on Earth, both natural processes and human-made processes, produce some type of byproduct from that activity. Under normal conditions these byproducts, some known as pollutants, are returned back into the environment.

Population and Water Resources

People use water for drinking, bathing, cooking, washing clothes, and maintaining lawns and gardens. Water also is used by the manufacturing sector to make products, by the agricultural industry to provide food, and by the energy industry to provide illumination, heat, and air conditioning.

Ports and Harbors

Foreign trade is vitally important to the United States economy and the international movement of goods and materials has highlighted the significance of harbor access and development issues. Natural harbors, typically in bays, estuaries, and river mouths, occur where land and water converges in such a way as to protect ships from wind and waves as they enter and dock.

Powell, John Wesley

John Wesley Powell began his river journeys by rowing up the Mississippi in 1855. He became a distinguished soldier, explorer, and manager of four federal agencies.

Precipitation and Clouds, Formation of

Clouds are condensed droplets or ice crystals from atmospheric water vapor. Clouds form by the rising and cooling of air caused by convection, topography, convergence, and frontal lifting.

Precipitation, Global Distribution of

The global distribution of precipitation is influenced by the general circulation of the atmosphere, proximity to large bodies of water, and topography. Precipitation is most abundant where air rises, and least abundant where it sinks.

Pricing, Water

An acquaintance once said that "every water faucet in New York City leaks." She was exaggerating, of course, but her point was that New Yorkers do not take the time or spend the money to repair leaks. Why?

Prior Appropriation

The prior appropriation doctrine is a legal concept that evolved in the American West as a means of establishing the right to use scarce water from rivers and streams. This doctrine can be summed up as "first in time is first in line." The prior appropriation doctrine is distinguished from the riparian doctrine, under which those who own land next to water have rights to use the water.

Privatization of Water Management

Privatization is the expansion of the private-sector role in water utility ownership, management, or operations.

Public Participation

Public participation is a process where each contributor gains a better understanding of both the issue(s) and how other participants see the issue(s). It is an opportunity for participants to share their facts, experiences, knowledge, ideas, preferences, hopes, fears, opinions, and values.

Pumps, Modern

A water pump is a machine used to increase the pressure of water in order to move it from one point to another. Modern water pumps are used throughout the world to supply water for municipal, industrial, agricultural, and residential uses.

Pumps, Traditional

Water devices, including pumps, are used for moving or lifting water from one location to another. Simple water devices have been in existence for thousands of years and were used for irrigation, domestic water needs, and livestock production.

Radioactive Chemicals

Radioactivity was discovered near the turn of the twentieth century through the work of Wilhelm RÃķentgen (1895, discovers X-rays), Antoine Becquerel (1896, discovers radioactivity), Marie and Pierre Curie (1898, isolates polonium and radium), and Ernest Rutherford (1899 and following years, identifies alpha, beta, and gamma radiation). Since that time, use of radioactive materials has made significant impacts in such areas as biology, chemistry, medicine, energy production, and nuclear weapons production.

Radionuclides in the Ocean

Sea water is slightly radioactive: it contains a small but significant amount of radioactive elements that undergo spontaneous radioactive decay and produce energy, subatomic particles, and a remainder, or daughter nucleus, smaller than the original. The particles include alpha particles (two neutrons plus two protons), beta particles (electrons), and gamma energy.

Rainwater Harvesting

The capture and storage of rainwater for subsequent utilization is called rainwater harvesting. Rainwater harvesting is often one component of a water management strategy in which a various water sources satisfy a spectrum of demands.

Reclamation and Reuse

As long as water remains inexpensive and plentiful, water reuse is not a high priority activity for water management. As water becomes more expensive, reclamation and reuse activities gain prominence as an alternative to increasing supplies.


Recreation is an essential and growing activity in the United States and the rest of the world. It is an activity that a person does for enjoyment, usually to refresh the body and mind.

Reisner, Marc

Marc Reisner, an award-winning author of popular environmental books, also was known for his conservation projects, "green" entrepreneurship, and provocative proposals to solve environmental problems. He is best known for his book Cadillac Desert, a history of the use and abuse of water in the American West.

Religions, Water in

Hindu women pray in the Old Brahmaputra River in central Bangladesh at the start of an annual 2-day religious ceremony. Hindus believe that bathing in the waters of a holy river, such as the Brahmaputra in Bangladesh and the Ganges in India, will purify one's life of past sins.


Four reptile groups have species found in aquatic habitats: turtles, lizards, snakes, and crocodilians. Although most must return to land to nest, many have adapted to spend the majority of their lives in water.