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Attribution of Chessie BIBI and fish sampling data to NHDPlusV2 Catchments within the Chesapeake Bay Watershed

March 10, 2022

This data release links fish survey data from a suite of programs in the Chesapeake Bay watershed as well the benthic macroinvertebrate sites included in the Chesapeake Bay Basin-wide Index of Biotic Integrity (Chessie BIBI) developed by the Interstate Commission on the Potomac River Basin (ICPRB) and available from the Chesapeake Bay Program. The data set contains site name, survey program, coordinates of sample, and ancillary information such as sample date and site location information where available. It also includes the NHDPlus V2.1 unique identifier, COMID, as well as a confidence classification category for each of these assignments based on a set of pre-determined rules. In total there were 15 confidence categories ranging from high confidence to low confidence. We caution the use of sampling points which were given anything other than "high" confidence in their assignment to a given NHD catchment/flowline to avoid spurious/inappropriate attribution of geospatial data to benthic macroinvertebrate and fish data samples represented herein and refer the potential user to the Confidence Dictionary.csv which describes the criteria for each confidence category.