This dataset contains watershed means of estimated percent impervious surfaces for three time periods: 1992, 2002, and 2012. Estimates are based on coefficients derived from comparing land use of the 2012 NAWQA Wall-to-wall Anthropogenic Land-use Trends (NWALT) product to the 2011 National Land Cover Database (NLCD) imperviousness, then applying those coefficients to previous years (1974-2002) of the NWALT dataset.

This data release contains three 10-meter resolution GeoTIFFs representing 10-meter (35-foot), 30-meter (100-foot) and 90-meter (300-foot) riparian buffer zones along shorelines, rivers, streams, and other lotic (flowing) water features. The layers are binary, where the value of each cell represents the presence or absence of the buffer zone. In addition, the data release contains shapefile layers that document the extent of corrections that were made to the data to address errors in the stream network (see processing steps section for more details).. The methodology combines various fine-scale input layers, including a 1:24k stream network and Chesapeake Bay 1-meter resolution Land Use/Land Cover to approximate banks of stream channels and waterbodies to better define the riparian zone (CBP, 2023; Hopkins and others, 2020). For shorelines and large rivers, the width of the buffer zone (10, 30, 90 meters) begins at the banks, where land meets water. For finer scale (1:24k) stream features, the buffer zone includes both water and riparian land area, where the buffered width begins at the estimated top of bank. Each 10-meter resolution riparian buffer zone GeoTIFF dataset is contained in an individual .zip file (CBW_riparian_10m_24k_2024.zip, CBW_riparian_30m_24k_2024.zip, CBW_riparian_90m_24k_2024.zip). The shapefile layers that contain the data correction extents are available in the correction_layers.zip file.

The Chesapeake Bay Hyper-Resolution Hydrography Database is intended to facilitate analysis of the landscape in the Chesapeake Bay watershed through identification of headwater and other low-order streams or drainage features (e.g. ditches) that, to date, may be absent from existing hydrography data products. A full description of the methodology and accuracy assessment is provided in the accompanying report titled: "Hydrography Mapping Supporting Modeling and Targeted Conservation: Project Overview and Lessons Learned". The data products were developed by the Chesapeake Conservancy and the University of Maryland Baltimore County (UMBC) as part of a 6-year Cooperative Agreement between the Chesapeake Conservancy and the U.S. Environmental Protection Agency (EPA) and a separate Interagency Agreement between the USGS and the EPA to provide geospatial support to the Chesapeake Bay Program Office. The data release is structured by eight-digit level hydrologic unit codes (HUC8) for the Chesapeake Bay watershed. Each HUC8 contains seven files (see below) and uses the following nomenclature: where HUC_ID and WATERSHED_NAME are placeholders for HUC8 ID(s), and local watershed name(s) (e.g., "Hydrographic Datasets for Hydrologic Unit 02050101 - Upper Susquehanna") Data Release Structure: Project Overview and Lessons Learned.pdf (Project overivew, methodology and accuracy assessment) huc_[HUC_ID]_streamLine.zip (Stream Lines) huc_[HUC_ID]_streamPoly.zip (Stream Polygons) huc_[HUC_ID]_agDitches.zip (Agricultural Ditches) huc_[HUC_ID]_rdDitches.zip (Road Ditches) huc_[HUC_ID]_geomorphon1m.tif (Geomorphon 1-meter) huc_[HUC_ID]_geomorphon10m.tif (Geomorphon 10-meter) metadata_[HUC_ID].xml (metadata xml)

The Chesapeake Bay Hyper-Resolution Hydrography Database is intended to facilitate analysis of the landscape in the Chesapeake Bay watershed through identification of headwater and other low-order streams or drainage features (e.g. ditches) that, to date, may be absent from existing hydrography data products. A full description of the methodology and accuracy assessment is provided in the accompanying report titled: "Hydrography Mapping Supporting Modeling and Targeted Conservation: Project Overview and Lessons Learned". The data products were developed by the Chesapeake Conservancy and the University of Maryland Baltimore County (UMBC) as part of a 6-year Cooperative Agreement between the Chesapeake Conservancy and the U.S. Environmental Protection Agency (EPA) and a separate Interagency Agreement between the USGS and the EPA to provide geospatial support to the Chesapeake Bay Program Office. The data release is structured by eight-digit level hydrologic unit codes (HUC8) for the Chesapeake Bay watershed. Each HUC8 contains seven files (see below) and uses the following nomenclature: where HUC_ID and WATERSHED_NAME are placeholders for HUC8 ID(s), and local watershed name(s) (e.g., "Hydrographic Datasets for Hydrologic Unit 02050101 - Upper Susquehanna") Data Release Structure: Project Overview and Lessons Learned.pdf (Project overivew, methodology and accuracy assessment) huc_[HUC_ID]_streamLine.zip (Stream Lines) huc_[HUC_ID]_streamPoly.zip (Stream Polygons) huc_[HUC_ID]_agDitches.zip (Agricultural Ditches) huc_[HUC_ID]_rdDitches.zip (Road Ditches) huc_[HUC_ID]_geomorphon1m.tif (Geomorphon 1-meter) huc_[HUC_ID]_geomorphon10m.tif (Geomorphon 10-meter) metadata_[HUC_ID].xml (metadata xml)

Hydrographic and Impairment Statistics (HIS) is a National Park Service (NPS) Water Resources Division (WRD) project established to track certain goals created in response to the Government Performance and Results Act of 1993 (GPRA). One water resources management goal established by the Department of the Interior under GRPA requires NPS to track the percent of its managed surface waters that are meeting Clean Water Act (CWA) water quality standards. This goal requires an accurate inventory that spatially quantifies the surface water hydrography that each bureau manages and a procedure to determine and track which waterbodies are or are not meeting water quality standards as outlined by Section 303(d) of the CWA. This project helps meet this DOI GRPA goal by inventorying and monitoring in a geographic information system for the NPS: (1) CWA 303(d) quality impaired waters and causes; and (2) hydrographic statistics based on the United States Geological Survey (USGS) National Hydrography Dataset (NHD). Hydrographic and 303(d) impairment statistics were evaluated based on a combination of 1:24,000 (NHD) and finer scale data (frequently provided by state GIS layers).

Hydrographic and Impairment Statistics (HIS) is a National Park Service (NPS) Water Resources Division (WRD) project established to track certain goals created in response to the Government Performance and Results Act of 1993 (GPRA). One water resources management goal established by the Department of the Interior under GRPA requires NPS to track the percent of its managed surface waters that are meeting Clean Water Act (CWA) water quality standards. This goal requires an accurate inventory that spatially quantifies the surface water hydrography that each bureau manages and a procedure to determine and track which waterbodies are or are not meeting water quality standards as outlined by Section 303(d) of the CWA. This project helps meet this DOI GRPA goal by inventorying and monitoring in a geographic information system for the NPS: (1) CWA 303(d) quality impaired waters and causes; and (2) hydrographic statistics based on the United States Geological Survey (USGS) National Hydrography Dataset (NHD). Hydrographic and 303(d) impairment statistics were evaluated based on a combination of 1:24,000 (NHD) and finer scale data (frequently provided by state GIS layers).

The Chesapeake Bay Hyper-Resolution Hydrography Database is intended to facilitate analysis of the landscape in the Chesapeake Bay watershed through identification of headwater and other low-order streams or drainage features (e.g. ditches) that, to date, may be absent from existing hydrography data products. A full description of the methodology and accuracy assessment is provided in the accompanying report titled: "Hydrography Mapping Supporting Modeling and Targeted Conservation: Project Overview and Lessons Learned". The data products were developed by the Chesapeake Conservancy and the University of Maryland Baltimore County (UMBC) as part of a 6-year Cooperative Agreement between the Chesapeake Conservancy and the U.S. Environmental Protection Agency (EPA) and a separate Interagency Agreement between the USGS and the EPA to provide geospatial support to the Chesapeake Bay Program Office. The data release is structured by eight-digit level hydrologic unit codes (HUC8) for the Chesapeake Bay watershed. Each HUC8 contains seven files (see below) and uses the following nomenclature: where HUC_ID and WATERSHED_NAME are placeholders for HUC8 ID(s), and local watershed name(s) (e.g., "Hydrographic Datasets for Hydrologic Unit 02050101 - Upper Susquehanna") Data Release Structure: Project Overview and Lessons Learned.pdf (Project overivew, methodology and accuracy assessment) huc_[HUC_ID]_streamLine.zip (Stream Lines) huc_[HUC_ID]_streamPoly.zip (Stream Polygons) huc_[HUC_ID]_agDitches.zip (Agricultural Ditches) huc_[HUC_ID]_rdDitches.zip (Road Ditches) huc_[HUC_ID]_geomorphon1m.tif (Geomorphon 1-meter) huc_[HUC_ID]_geomorphon10m.tif (Geomorphon 10-meter) metadata_[HUC_ID].xml (metadata xml)

This metadata report documents a shapefile of watershed boundaries for 84 selected United States Geological Survey (USGS) water quality stations that are part of the Chesapeake Bay non-tidal network (NTN).

The Chesapeake Bay Hyper-Resolution Hydrography Database is intended to facilitate analysis of the landscape in the Chesapeake Bay watershed through identification of headwater and other low-order streams or drainage features (e.g. ditches) that, to date, may be absent from existing hydrography data products. A full description of the methodology and accuracy assessment is provided in the accompanying report titled: "Hydrography Mapping Supporting Modeling and Targeted Conservation: Project Overview and Lessons Learned". The data products were developed by the Chesapeake Conservancy and the University of Maryland Baltimore County (UMBC) as part of a 6-year Cooperative Agreement between the Chesapeake Conservancy and the U.S. Environmental Protection Agency (EPA) and a separate Interagency Agreement between the USGS and the EPA to provide geospatial support to the Chesapeake Bay Program Office. The data release is structured by eight-digit level hydrologic unit codes (HUC8) for the Chesapeake Bay watershed. Each HUC8 contains seven files (see below) and uses the following nomenclature: where HUC_ID and WATERSHED_NAME are placeholders for HUC8 ID(s), and local watershed name(s) (e.g., "Hydrographic Datasets for Hydrologic Unit 02050101 - Upper Susquehanna") Data Release Structure: Project Overview and Lessons Learned.pdf (Project overivew, methodology and accuracy assessment) huc_[HUC_ID]_streamLine.zip (Stream Lines) huc_[HUC_ID]_streamPoly.zip (Stream Polygons) huc_[HUC_ID]_agDitches.zip (Agricultural Ditches) huc_[HUC_ID]_rdDitches.zip (Road Ditches) huc_[HUC_ID]_geomorphon1m.tif (Geomorphon 1-meter) huc_[HUC_ID]_geomorphon10m.tif (Geomorphon 10-meter) metadata_[HUC_ID].xml (metadata xml)

The Chesapeake Bay Hyper-Resolution Hydrography Database is intended to facilitate analysis of the landscape in the Chesapeake Bay watershed through identification of headwater and other low-order streams or drainage features (e.g. ditches) that, to date, may be absent from existing hydrography data products. A full description of the methodology and accuracy assessment is provided in the accompanying report titled: "Hydrography Mapping Supporting Modeling and Targeted Conservation: Project Overview and Lessons Learned". The data products were developed by the Chesapeake Conservancy and the University of Maryland Baltimore County (UMBC) as part of a 6-year Cooperative Agreement between the Chesapeake Conservancy and the U.S. Environmental Protection Agency (EPA) and a separate Interagency Agreement between the USGS and the EPA to provide geospatial support to the Chesapeake Bay Program Office. The data release is structured by eight-digit level hydrologic unit codes (HUC8) for the Chesapeake Bay watershed. Each HUC8 contains seven files (see below) and uses the following nomenclature: where HUC_ID and WATERSHED_NAME are placeholders for HUC8 ID(s), and local watershed name(s) (e.g., "Hydrographic Datasets for Hydrologic Unit 02050101 - Upper Susquehanna") Data Release Structure: Project Overview and Lessons Learned.pdf (Project overivew, methodology and accuracy assessment) huc_[HUC_ID]_streamLine.zip (Stream Lines) huc_[HUC_ID]_streamPoly.zip (Stream Polygons) huc_[HUC_ID]_agDitches.zip (Agricultural Ditches) huc_[HUC_ID]_rdDitches.zip (Road Ditches) huc_[HUC_ID]_geomorphon1m.tif (Geomorphon 1-meter) huc_[HUC_ID]_geomorphon10m.tif (Geomorphon 10-meter) metadata_[HUC_ID].xml (metadata xml)