User:Jes029/Point source water pollution

Introduction
Water pollution is the contamination of natural water bodies by chemical, physical, radioactive or pathogenic microbial substances. Point sources of water pollution are discrete conveyances such as pipes or man-made ditches from stationary locations such as sewage treatment plants, factories, wastewater treatment facilities, septic systems, ships, and other sources that are clearly discharging pollutants into water sources.

Background
Water pollution interferes with the natural characteristics of water and fundamentally changes the biological, chemical, or physical composition of the water. There are a variety of water quality parameters that may be impacted by point source water pollution. They include: dissolved oxygen and biochemical oxygen demand (BOD), temperature, pH, turbidity, phosphorus, nitrates, total suspended solids (TSS), conductivity, alkalinity, and fecal coliform. Different types of point source water pollution impair water quality in different ways. Some water pollutants are directly toxic to humans or other organisms, while others may indirectly threaten water quality.

Historical
Historically, there have been two major pieces of legislation that have regulated water pollution. The River and Harbor Act of 1899 made discharging refuse matter into navigable waters of the United States illegal without a permit issued by the Army Corps of Engineers. The Federal Water Pollution Control Act of 1948 (FWPCA) has been amended several times since it was created and contains a variety of provisions to decrease water pollution from point sources.

Current
Regulation of point-source pollution is carried out by the Clean Water Act (actually an amendment of FWPCA), which regulates discharges into navigable waters in the United States by setting effluent guidelines designed to “force industry to adopt the latest available technology." These effluent guidelines set limits for dischargers to keep contaminant levels at or below the standard; contaminant levels vary by state and by body of water. A facility that wishes to discharge pollutants must first obtain a National Pollution Discharge Elimination (NPDES) permit, which is designed to control water pollution levels (Clean Water Act). The EPA has regulatory oversight of the Clean Water Act while individual states are authorized to carry out the NPDES Program, which handles permitting, enforcement, and administrative functions of the program.

International Examples
There are a variety of examples of point source water pollution regulation in other countries. Many of these have similar provisions to the CWA. In the Netherlands, for example, it is forbidden to discharge waste matter, pollutants or hazardous substances, in whatever form, into surface waters without a permit. However, in seeking to control point-source pollution and achieve greater improvement in environmental quality, the country is working with corporate to develop new and cleaner processes and to supplement or replace end-of-pipe measures by 'in process' solutions and preventive action. This involves a mix of instruments that will restrict the use of permits to requirements concerning the most important environmental issues.

Future Issues
The Clean Water Act has made great strides in reducing point source water pollution, but this effect is overshadowed by the fact that non-point source pollution, which is not subject to regulation under the Act, has correspondingly increased. To sustain clean water for the future, regulatory changes will need to occur and/or new programs will need to be implemented. Non-point sources are inherently harder to regulate and they also currently represent the primary cause of impaired surface water quality. Consequently, one of the solutions to address this imbalance is point/non-point source trading of pollutants. Under a water quality trading system like this, point sources would be allowed to purchase pollutant loadings from non-point sources in order to avoid reducing their own pollutant loadings. An implicit difficulty in implementing such a system though is the establishment of a “trading ratio.” Also, a market for water quality trading can only exist if there are differential costs and opportunities of pollution reduction across point and non-point sources. Mathematical models represent an important tool that can be utilized to assess future impacts of point source and non-point source water pollution. Whether they are global or local in scale, models can supplement real data and fill in information gaps, which makes the crucial for providing the “what if capability” required for future regulation and remediation.