The National Hydrography Dataset (NHD) is used to portray surface water. The NHD represents the drainage network with features such as rivers, streams, canals, lakes, ponds, coastline, etc. The principal components of the NHD are: NHDFlowline: This is the fundamental … Continued
Hydrography depicts surface water, including rivers and streams, lakes and ponds, canals, coastlines, and many other water features. The Hydrography layer combines two data sets: the 2014 National Map Hydrographic Geodatabase (1:1,000,000 scale) for small to medium scales, and the … Continued
The National Wetlands Inventory (NWI) provides detailed information on the characteristics and distribution of wetlands in the United States. This update incorporates many changes, including the representation of wetland areas for intermittent streams.
This layer displays United States Army Core of Engineers surveyed Floodwalls. The USACE defines an Floodwall as a structure erected to protect areas from high river stages. For more information about USACE data, visit the National Levee Database here .
This layer displays United States Army Core of Engineers surveyed Leveed Areas. The USACE defines a Levee Areas as the area of a floodplain from which flood water is excluded by the levee system. For more information about USACE data, … Continued
This layer displays United States Army Core of Engineers surveyed Embankments. The USACE defines an Embankment as the area of a floodplain from which flood water is excluded by the levee system. For more information about USACE data, visit the … Continued
This layer displays the amount of toxic releases based on the Environmental Protection Agency (EPA) Toxics Release Inventory (TRI), a national program which tracks the management of over 650 toxic chemicals that pose a threat to human health and the … Continued
This layer displays the locations of a subset of the Environmental Protection Agency (EPA) Safe Drinking Water Information System (SDWIS) sites. The SDWIS contains information about public water systems and their violations of EPA’s drinking water regulations. Data can be … Continued
The National Hydrography Dataset (NHD) is used to portray surface water. The NHD represents the drainage network with features such as rivers, streams, canals, lakes, ponds, coastline, etc. The principal components of the NHD are: NHDFlowline: This is the fundamental … Continued
Hydrography depicts surface water, including rivers and streams, lakes and ponds, canals, coastlines, and many other water features. The Hydrography layer combines two data sets: the 2021 National Map Hydrographic Geodatabase (1:1,000,000 scale) for small to medium scales, and the … Continued