The last update to this data was completed on 6/22/2020, this update focused on reviewing existing waterbodies and folding in missing waterbodies for the Chemung HUC (02050105) and the Tioga HUC (02050104). A History of edits is listed below. The full statewide dataset can be downloaded from: https://www.usgs.gov/national-hydrography/access-national-hydrography-productsWeb Service url - https://gisservices.its.ny.gov/arcgis/rest/services/NYS_Hydrography_HollowFill/MapServerThis web service is a subset for New York State of the National Hydrography Dataset (NHD), there is more information about each layer in the description of the groups and specific layers. The NHD is a feature-based database that interconnects and uniquely identifies the stream segments or reaches that make up the nation's surface water drainage system. NHD data was originally developed at 1:100,000-scale and exists at that scale for the whole country. This high-resolution NHD, generally developed at 1:24,000/1:12,000 scale, adds detail to the original 1:100,000-scale NHD. Local resolution NHD is being developed where partners and data exist. The NHD contains reach codes for networked features, flow direction, names, and centerline representations for areal water bodies. Reaches are also defined on waterbodies and the approximate shorelines of the Great Lakes and the Atlantic Ocean. The NHD also incorporates the National Spatial Data Infrastructure framework criteria established by the Federal Geographic Data Committee. -- History of edits 02/18/2020 -- Waterbody Updates to Southern Long Island HUC (02030202) & Owego-Wappasening HUC (02050103) 10/04/2019 – Waterbody Updates to Upper Susquehanna HUC (02050101) 08/19/2019 – Waterbody Updates to Chenango HUC (02050102) & Northern Long Island HUC (02030201)Please contact NYS ITS Geospatial Services at nysgis@its.ny.gov if you have any questions.

The last update to this data was completed on 6/22/2020, this update focused on reviewing existing waterbodies and folding in missing waterbodies for the Chemung HUC (02050105) and the Tioga HUC (02050104). A History of edits is listed below. The full statewide dataset can be downloaded from: https://www.usgs.gov/national-hydrography/access-national-hydrography-products

Web Service url - https://gisservices.its.ny.gov/arcgis/rest/services/NYS_Hydrography/MapServer

This web service is a subset for New York State of the National Hydrography Dataset (NHD), there is more information about each layer in the description of the groups and specific layers. The NHD is a feature-based database that interconnects and uniquely identifies the stream segments or reaches that make up the nation's surface water drainage system. NHD data was originally developed at 1:100,000-scale and exists at that scale for the whole country. This high-resolution NHD, generally developed at 1:24,000/1:12,000 scale, adds detail to the original 1:100,000-scale NHD. Local resolution NHD is being developed where partners and data exist. The NHD contains reach codes for networked features, flow direction, names, and centerline representations for areal water bodies. Reaches are also defined on waterbodies and the approximate shorelines of the Great Lakes and the Atlantic Ocean. The NHD also incorporates the National Spatial Data Infrastructure framework criteria established by the Federal Geographic Data Committee. -- History of edits 02/18/2020 -- Waterbody Updates to Southern Long Island HUC (02030202) & Owego-Wappasening HUC (02050103) 10/04/2019 – Waterbody Updates to Upper Susquehanna HUC (02050101) 08/19/2019 – Waterbody Updates to Chenango HUC (02050102) & Northern Long Island HUC (02030201)Please contact NYS ITS Geospatial Services at nysgis@its.ny.gov if you have any questions.