The State Water Control Law mandates the protection of existing high-quality state waters and provides for the restoration of all other state waters so they will permit reasonable public uses and will support the growth of aquatic life. The adoption of water quality standards under Section 62.1-44.15(3a) of the law is one of the State Water Control Board's methods of accomplishing the law's purpose.

Water quality standards consist of statements that describe water quality requirements. They also contain numeric limits for specific physical, chemical, biological or radiological characteristics of water. These statements and numeric limits describe water quality necessary to meet and maintain uses such as swimming and other water-based recreation, public water supply, and the propagation and growth of aquatic life.

Standards include general and specific descriptions, because not all requirements for water quality protection can be numerically defined. The standards will be adjusted constantly to reflect changes in law, technology and information available to the Water Board and DEQ.

The standards are intended to protect all state waters for recreation, wildlife, the growth of a balanced population of aquatic life, and the production of edible and marketable fish and shellfish. Through the protection of these uses, other uses such as industrial water supply, irrigation and navigation also are usually protected. Should additional standards be needed to protect other uses as dictated by changing circumstances or improved knowledge, they will be adopted.

What are Water Quality Standards?

Water quality standards consist of statements that describe water quality requirements. Water quality standards must have at least the following three components:

• Designated Uses
• Water Quality Criteria to Protect Designated Uses
• Antidegradation Policy