Water and Wastewater covers a broad and expansive industry.  It covers water distribution, waste & water treatment, water purification water desalination and water reclamation.  The modern water industry alone typically represents 1-2% of GDP of a given region. 

Wastewater is any water that has been adversely affected in quality by anthropogenic influence. It comprises liquid waste discharged by domestic residences, commercial properties, industry, and/or agriculture and can encompass a wide range of potential contaminants and concentrations. In the most common usage, it refers to the municipal wastewater that contains a broad spectrum of contaminants resulting from the mixing of wastewaters from different sources.

Sewage is correctly the subset of wastewater that is contaminated with feces or urine, but is often used to mean any waste water. "Sewage" includes domestic, municipal, or industrial liquid waste products disposed of, usually via a pipe or sewer or similar structure, sometimes in a cesspool emptier.

The physical infrastructure, including pipes, pumps, screens, channels etc. used to convey sewage from its origin to the point of eventual treatment or disposal is termed sewerage. 

This business is usually run as a public service by a public utility which is owned by local or national government as it usually represents monopolistic characteristics. In some countries, the water industry is regulated but services are largely operated by private companies.

Water pollution and taste treatment is a major problem in the global context and many believe that it is the leading worldwide cause of deaths and diseases.  Estimates have been made that water pollution accounts for the deaths of more than 14,000 people daily.  In addition to the acute problems of water pollution in developing countries, industrialized countries continue to struggle with pollution problems as well.

Investing in water purification, water desalinization, water reclamation and other water investments can be done through investement in companies that manufacture water infrastructure, water equipment or water treatment solutions.  There are many exchange traded water funds and structured investment products that are tied to water indices.  These are offered as closed-end fund products and as open-ended fund products.  There are also water ETF's that trade on the NYSE.

Water Pollution Categories

Surface water and groundwater have often been studied and managed as separate resources, although they are interrelated. Sources of surface water pollution are generally grouped into two categories based on their origin.

Point source pollution

Point source pollution refers to contaminants that enter a waterway through a discrete conveyance, such as a pipe or ditch. Examples of sources in this category include discharges from a sewage treatment plant, a factory, or a city storm drain. The U.S. Clean Water Act (CWA) defines point source for regulatory enforcement purposes.

Non-point source pollution

Non-point source (NPS) pollution refers to diffuse contamination that does not originate from a single discrete source. NPS pollution is often a cumulative effect of small amounts of contaminants gathered from a large area. Nutrient runoff in stormwater from "sheet flow" over an agricultural field or a forest are sometimes cited as examples of NPS pollution.

Contaminated stormwater washed off of parking lots, roads and highways, called urban runoff, is sometimes included under the category of NPS pollution. However, this runoff is typically channeled into storm drain systems and discharged through pipes to local surface waters, and is a point source. The CWA definition of point source was amended in 1987 to include municipal storm sewer systems, as well as industrial stormwater, such as from construction sites.^[6]

Groundwater pollution

Interactions between groundwater and surface water are complex. Consequently, groundwater pollution, sometimes referred to as groundwater contamination, is not as easily classified as surface water pollution. By its very nature, groundwater aquifers are susceptible to contamination from sources that may not directly affect surface water bodies, and the distinction of point vs. nonpoint source may be irrelevant. A spill of a chemical contaminant on soil, located away from a surface water body, may not necessarily create point source or non-point source pollution, but nonetheless may contaminate the aquifer below. Analysis of groundwater contamination may focus on soil characteristics and hydrology, as well as the nature of the contaminant itself.

This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Water Pollution"