The Water (Prevention and Control of Pollution) Act of 1974 was the first important environmental legislation in India. Before the enactment of the Act, there were few initiatives to legislate pollution control at the national level. A Committee that reviewed existing laws found that a comprehensive legislation to address the issue of water pollution in the country was inadequate. On the prompting of various states, a bill introduced in the Rajya Sabha in 1962 and was examined by the Select and Joint Committees of Parliament. The bill sought to provide for the establishment of agencies at the Central and State levels to provide for the prevention, abatement and control of pollution of rivers and streams, for maintaining and restoring the wholesomeness of such water and for controlling existing and new discharges of domestic and industrial wastes.

Water is a subject in the State List of the Constitution. The Act was enacted as a central law in pursuance of Article 252(1) of the Constitution which empowers the Union Government to legislate in a field reserved for the states, where two or more State Legislatures pass a resolution consenting to a central law.  All States have adopted the implementation of the Act as enacted in 1974.

The Act provided for the establishment of administrative boards under the executive branch of the Central and State governments. The powers and functions assigned to the boards broadly include the setting of standards (for effluent and sewage disposal) and advising the government on measures to combat pollution. The State Boards have the authority to grant consent to the use of new or existing disposal systems, and may impose certain conditions on the grant of such consent.
The law provides for penalties for the contravention of the provisions of the Act, which includes the failure to comply with the directives of the State Board.
It also provides for the establishment of Central and State water testing laboratories whose primary functions are to aid in the setting of standards, and for testing of water samples collected and analyzed under the provisions of the Act, to ensure compliance with the standards enforced or to establish contravention of the same.

The law defines pollution as “such contamination of water or such alteration of the physical, chemical or biological properties of water or such discharge of any sewage or trade effluent or of any other liquid, gaseous or solid substance into water (whether directly or indirectly), as may, or is likely to, create a nuisance or render such water harmful or injurious to public health or safety, or to domestic, commercial, industrial, agricultural or other legitimate uses, or to the life and health of animals or plants or of aquatic organisms”
The application of the Act covers streams, inland waters, subterranean waters, and sea or tidal waters.

The Water (Prevention and Control of Pollution) Act as it appears in this guide

The Bare Act has been divided into four sections:

Authorities/Boards and Laboratories – this section lists out authorities appointed under the Act by the Central Government and the State Governments for implementation of the Act. The central board and state boards are responsible for the implementation of the Act, and this function is assisted by committees that the board may set up for the purpose. Laboratories and analysts at the Central and State levels so recognized by the respective government or board carry out the functions of analysis of samples to ensure compliance to standards laid down. The report of such analysis may also be used in a court of law as evidence for defaulting provisions of the law.

Procedures –This section lists out the procedures carried out by various authorities for achieving the objectives of the Act; the control and abatement of water pollution.

Collection and analysis of samples: State Boards are empowered to collect water samples (or authorize a person to exercise this power) in order to ensure compliance to standards laid down for effluent discharge. The procedure by which the samples are collected, and then analyzed by the respective laboratory have been elaborated upon in this section.
Laying down of standards: Although standards are not specified within the Act, it empowers the Boards to establish and enforce effluent standards.
Procedures for State Board to carry out procedures: The Act empowers the State Board, upon thirty days notice to a polluter, to execute any work required under a consent order which has not been executed. (The procedure for grant of consent is discussed in the section on ‘Regulations and Prohibitions’).
Appeals: Under the Act, the State Board grants consent for the use of new or existing disposal systems and may impose certain conditions (see section on ‘Regulations and Prohibitions’). A person may prefer an appeal to the appellate authority constituted for this purpose, if aggrieved by the rejection of an application for consent or by the conditions imposed on the grant of consent.

Regulations and Prohibitions – this section includes activities that are prohibited or may be regulated under the Act. Section 21 of the Act prohibits the disposal of polluting matter into a stream or well in excess of the standards laid down.

The use of new or existing disposal systems (i.e. in  existence prior to the commencement of the Act) requires the consent of the State Board which must ensure that the standards laid down for effluent discharge are complied with, and to do so, the Board may impose conditions along with the grant of such consent.  

Offences and Penalties – The Amendment Act 1988 strengthened the penalties provided in the original Act of 1974. Failure to comply with orders or directions of the State Board, knowingly exceeding prescribed standards of effluents in discharge, carrying on activities without the consent of the State Board where such consent is mandatory, amount to offences under the Act and penalties (including penalties for subsequent offences of similar nature) have been specified in the Act.

Apart from these sections, the following from the Bare Act have been provided: Definitions, Power of the Central and State Government to make rules and Repeal and Saving.
Amendments, Notifications, Rules and Guidelines are also provided in downloadable pdf formats.