Problem:  Water-resource planning and water-quality assessment require a statewide base level of standardized information.  For planning and assessment of the water resource, the chemical and physical quality of the streams must be defined and monitored.

Objective: To provide a State-wide base of water-quality data for broad State and Federal planning and action programs, provide data for Federal management of interstate water, and develop a data base against which the short-term records acquired in areal studies can be compared.

Relevance and Benefits: An important part of the USGS mission is to provide scientific information to manage the water resources of the Nation. To effectively assess the quality of the Nation's surface-water and ground-water resources, the USGS collects water-quality data from rivers, lakes, estuaries, and ground-water aquifers. Water-quality data are published in annual data reports, and an increasing amount of real-time and historical water-quality data are available on the World Wide Web. The data, collected using standardized instruments and procedures, contribute to a nationally consistent data set for assessment of the water quality of the Nation. Long-term water-quality data characterize the physical, chemical,and biological changes in our water resources in response to natural processes including climatic variations, storms, floods, droughts, volcanic eruptions, and a variety of human activities that exert an influence on water-quality conditions. The data are useful in designing programs to protect watersheds, sensitive aquatic habitats, biota, and drinking water sources from urban and agricultural runoff, sewage, and industrial and mining wastes. The data are also useful in designing programs to maintain waterways for other designated beneficial uses such as navigation, aesthetics, contact recreation, and to meet national and international treaty obligations. The water-quality data collected in this State are an integral part of the nationwide water-quality data program.

Approach: Operation of a network of water-quality stations to provide chemical concentrations, loads, and temporal trends as required by planning and management agencies.  The network is designed to: (1) Selectively monitor all major rivers within Virginia, (2) obtain comprehensive description of chemical composition and loads for major hydrologic units as part of nationwide overviews, and (3) provide long-term monitoring of natural hydrologic conditions in selected areas minimally affected by man.  The hydrologic network is periodically analyzed to define the statistical properties of, and trends in, the quality of water and needs for network changes.