Irma Basemap - Boundaries and Hydrology Data

This resource contains medium-resolution (1:100k) National Hydrography Dataset (NHDPlus) [1] map data for a region of 23 Hydrologic Unit Code (HUC) 6-digit (HUC6) basins around the Hurricane Irma impact zone across Florida, Georgia, and the Carolinas. This includes 5,236 subwatersheds, 217,308 catchments, and 220,418 flowlines.

State and county boundaries were obtained from the Esri Living Atlas [2].

USGS active stream gages can be downloaded from the USGS National Water Information System (NWIS) [3], or visualized at the USGS WaterWatch site [4].
NOAA Advanced Hydrologic Prediction System (AHPS) river forecast points can be downloaded as well [5]. Many of these are co-located with USGS NWIS gages to leverage authoritative observation data.

References
[1] NHDPlus Version 2 [http://www.horizon-systems.com/NHDPlus/V2NationalData.php]
[2] Esri Living Atlas [https://livingatlas.arcgis.com]
[3] USGS NWIS [https://waterdata.usgs.gov/nwis]
[4] USGS WaterWatch [https://waterwatch.usgs.gov]
[5] NOAA AHPS [https://water.weather.gov/ahps/forecasts.php]