NYSHD Web Services
NYSHD Status
NYSHD Update (Post NHD)
We are using hydro breaklines generated through the USGS 3DEP process as well as reviewing existing hydrography to update this dataset. Our goal is to pick up where we left off with updating the NHD using a similar process outlined below.
NYSHD Waterbody Update Process
The primary focus at this stage is to review existing waterbodies and utilize the 3D derived USGS 3DEP hydro-breaklines that are 2 acres and above. The typical update process for an 8 digit Hydrologic Unit Code (HUC) is explained below.
- Review existing waterbodies to see if they are still valid
- Edit any existing waterbodies that are not spatially correct. These are edited to the most recent orthoimagery from the NYS Digital Ortho Program (NYSDOP)
- Replace geometry where hydro breaklines are available from the 3DEP Program. Attributes will be retained and the source of update will be included
- Add any breaklines that are not included in the waterbody feature class
- Delete any waterbodies that are no longer relevant
NYSHD Area Update Process
The hydrography area layer represents major rivers and stream polygons. One of the deliverables for 3DEP breaklines is rivers and streams with a nominal width of 30 meters or wider. These breaklines will be used similarly to the waterbody update process explained above. Area features that cannot be updated via the breakline file will be reviewed and realigned to orthoimagery at a scale of 1:3000
Samples of Hydrography Edits
Waterbodies removed that are no longer valid
Waterbody needing spatial improvement (before edit)
Waterbody needing spatial improvement (after edit)
Waterbody needing replacement using available hydro breaklines (before edit)
Waterbody needing replacement using available hydro breaklines (after edit)
Rivers/Streams needing realignment (before edit)
Rivers/Streams needing realignment (after edit)
NYS Hydrography History
NYS ITS signed a Memorandum of Understanding (MOU) with the United States Geological Survey (USGS) to become stewards for both the National Hydrography Dataset (NHD) and Watershed Boundary Dataset (WBD) in July of 2019. NYS ITS was able to update 7 HUCs with better hydro data before the NHD program was retired on October 1, 2023. NYS continues to update the statewide hydrography dataset while we look into becoming more involved in the USGS 3DHP. The USGS NHD Dataset remains available and can be accessed using the following links.