Data on the distribution, abundance and condition of aquatic and riparian biota are required to assess environmental flow needs in river systems. Ecological data are generally collected in site-specific studies by academic, government agencies, or private entities, are often not directly accessible on the web. Notable exceptions are bioassessment data collected by the U.S. Enviornmetnal Protection Agency and USGS.

USGS Water Quality Data 

The USGS collects and maintains water quality information from thousands of sites across the United States.

National Water-Quality Assessment Program (NAQWA)

NAWQA contains water quality data from across the United States that can be used to analyze trends in water quality conditions.

National Rivers and Streams Assessment (NRSA) 

The NRSA is an EPA-led survey of water quality and ecological health of the nation’s streams and rivers (completed in 2008).

Wadeable Streams Assessment (WSA) 

The WSA is a survey of ecological conditions of small streams throughout the Unites States (completed in 2005).

USGS BioData

BioData provides access to aquatic bioassessment data (biological community and physical habitat data) collected by USGS scientists from stream ecosystems across the nation.

National Fish Habitat Partnership

The National Fish Habitat Partnership provides data related to inland and coastal fish habitat in the United States.

Woody riparian vegetation near selected stream gages in the Western United States 

Areal cover and occupancy of woody riparian species near 456 stream gages in the western United States were obtained from site visits during the growing seasons of 1996–2002.

State bioassessment data

Most states conduct their own ecological surveys and collect bioassessment data. Check with states agencies for data availability.

Syan River Channel, Oregon. Photo by Oregon Water USGS.
Syan River Channel, Oregon. Photo by Oregon Water USGS.