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USGS Water-Quality Information

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The Hydrologic Benchmark Network

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What is HBN?

The Hydrologic Benchmark Network (HBN) was established in 1963 to provide long-term measurements of streamflow and water quality in areas that are minimally affected by human activities. These data were used to study long-term trends in surface water flow and water chemistry and as a benchmark against which to compare changes in flow and chemistry in developed watersheds. At its peak the network consisted of 58 drainage basins in 39 States. Over time, changes in funding and land use within the watersheds reduced the number of stations and samples collected by HBN. In the mid-1990s, the USGS conducted a complete review of the network, and selected 5 eastern stations to conduct a pilot study to assess the optimum sampling strategy for assessing long-and short-term trends. In 2003, the USGS re-established a 15-station water-quality and 36-station discharge monitoring network with a new design that allows tracking of trends in water quality at a range of river flow conditions. Additional stations are anticipated to be added to the network as funding allows.

The HBN Network

The HBN Network

= Hydrologic Benchmark Site List =

USGS Circular 1173 (Environmental Characteristics and Water Quality of Hydrologic Benchmark Stations in the United States, 1963-95) describes each station within the historic HBN and provides summary analysis of the water quality data collected.

Questions or comments?

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