Water quality law


Water quality laws
govern the release of pollutants into water resources, including surface water, ground water, and stored drinking water. Some water quality laws, such as drinking water regulations, may be designed solely with reference to human health. Many others, including restrictions on the alteration of the chemical, physical, radiological, and biological characteristics of water resources, may also reflect efforts to protect aquatic ecosystems more broadly. Regulatory efforts may include identifying and categorizing water pollutants, dictating acceptable pollutant concentrations in water resources, and limiting pollutant discharges from effluent sources. Regulatory areas include sewage treatment and disposal, industrial and agricultural waste water management, and control of surface runoff from construction sites and urban environments.

Regulated waters

The Earth's hydrosphere is ubiquitous, fluid, and complex. Within the water cycle, physical water moves without regard to political boundaries between the Earth's atmosphere, surface, and subsurface, through both natural and man-made channels. Consequently, water quality laws must define the portion of this complex system subject to regulatory control. Regulatory jurisdictions may be coterminous with political boundaries. Other laws may apply only to a subset of waters within a political boundary, or to a special class of water. Cross-jurisdictional waters may be subject to cross-jurisdictional agreements. Even within jurisdictions, complexities may arise where water flows between subsurface and surface, or saturates land without permanently inundating it.

Water pollutant classification

Water quality laws must identify the substances and energies which qualify as "water pollution" for purposes of further control. From a regulatory perspective, this requires defining the class of materials that qualify as pollutants, and the activities that transform a material into a pollutant.
For example, the United States Clean Water Act defines "pollution" very broadly to include any and all "man-made or man-induced alteration of the chemical, physical, biological, and radiological integrity of water." However, the Act defines "pollutants" subject to its control more specifically, as "dredged spoil, solid waste, incinerator residue, filter backwash, sewage, garbage, sewage sludge, munitions, chemical wastes, biological materials, radioactive materials , heat, wrecked or discarded equipment, rock, sand, cellar dirt and industrial, municipal, and agricultural waste discharged into water." This definition begins to define both the classes or types of materials and energies that may constitute water pollution, and indicates the moment at which otherwise useful materials may be transformed into pollution for regulatory purposes: when they are "discharged into water," defined elsewhere as "addition" of the material to regulated waters.
Regulatory regimes may also use definitions to reflect policy decisions, excluding certain classes of materials from the definition of water pollution that would otherwise be considered to constitute water pollution. For example, the CWA definition quoted above later excludes sewage discharged from certain classes of vessels, meaning that a common and important class of water pollution is, by definition, not considered a pollutant for purposes of the United States' primary water quality law.
Although thermal pollution is subject to regulation under the CWA, definitional questions have resulted in litigation, including whether even water itself may qualify as a "pollutant". The United States Supreme Court addressed these issues in Los Angeles County Flood Control District v. Natural Resources Defense Council, Inc..

Water quality standards

Ambient water quality standards

Water quality standards are legal standards or requirements governing water quality, that is, the concentrations of water pollutants in some regulated volume of water. Such standards are generally expressed as levels of a specific water pollutants that are deemed acceptable in the water volume, and are generally designed relative to the water's intended use - whether for human consumption, industrial or domestic use, recreation, or as aquatic habitat. Determining appropriate water quality standards generally requires up-to-date scientific data on the health or environmental effects of the pollutant under review. It also may require periodic or continuous monitoring of water quality. Regulatory decisions on water quality standards may also incorporate political considerations, such as the economic costs and benefits of compliance.
As an example, the United States employs water quality standards as part of its regulation of surface water quality under the CWA. The national Water Quality Standards Program begins with U.S. states designating intended uses for a surface water bodies, after which they develop science-based water quality criteria. The criteria include numeric pollutant concentration limits, narrative goals, and narrative biological criteria. If the water body fails the existing WQS criteria, the state must develop a Total Maximum Daily Load for pollutants of concern. Human activity impacting water quality will then be controlled via other regulatory means in order to achieve the TMDL targets.

Effluent limitations

Effluent limitations are legal requirements governing the discharge of pollutants into surface waters. Such standards set quantitative limits on the permissible amount of specific water pollutants that may be released from specific sources over specific timeframes. They are generally designed to achieve water quality standards for the receiving waterbody. Numerous methods exist for determining appropriate limitations.
Several approaches are used in the United States. The Clean Water Act requires the United States Environmental Protection Agency to develop effluent guidelines - national industry-specific effluent limitations based on the performance of existing control technologies. These limits set a basic national discharge standard for an industrial category, typically using a "best available technology economically achievable" standard for existing facilities, and a "best available demonstrated control technology" standard for new facilities. If the national standard is not sufficiently protective at a particular location, then water quality standards may be employed to develop more stringent limitations.
The effluent limitations for U.S. facilities are implemented in discharge permits issued by state agencies and EPA, under the National Pollutant Discharge Elimination System.

Drinking water standards

Water designated for human consumption as drinking water may be subject to specific drinking water quality standards. In the United States, for example, such standards have been developed under the Safe Drinking Water Act, are mandatory for public water systems, and are enforced via a comprehensive monitoring and correction program.

Dumping bans

Permitting, data collection, and access

Around the world

International law

and ship pollution are serious threats to the world's oceans. The London Convention limits ocean dumping from vessels, aircraft and platforms. MARPOL 73/78 also governs ship pollution.

Canada

The Canada Water Act is the principal federal law protecting Canadian waters. It is administered by Environment Canada.
Guidelines for Canadian Drinking Water Quality contains federal drinking water standards. It is administered by Health Canada.

United States

The Clean Water Act is the primary federal law in the United States governing water pollution, and is administered by EPA and state environmental agencies.
Groundwater is protected at the federal level principally through two laws:
Both laws are administered by EPA and state agencies.
The SDWA governs public water systems in the United States, and is administered by EPA and states. Bottled water is regulated by the Food and Drug Administration under the Federal Food, Drug, and Cosmetic Act.