AIS has been contracted multiple times by the New Jersey Department of Environmental Protection (NJDEP) to create their statewide land use/land cover (LU/LC) and impervious surface (IS) dataset and to perform periodic statewide updates of the data.
The original LU/LC data layer was created by AIS in the late 1980s as part of NJDEP’s Integrated Terrain Unit Map (ITUM) project. At that time, AIS produced an Anderson Level II land use/land cover layer for the ITUM in conjunction with soils, geology, and flood prone data. Since then, AIS has utilized Anderson Level III classes in updating the LU/LC dataset to conditions in 1997, 2002, 2007 and 2012. Beginning with the 1997 update, percentages of impervious surface have been assessed as part of the mapping effort, adding detail to the LU/LC interpretations where necessary.
The updates were performed using color infrared (CIR) digital images, Esri GIS software and computer interactive photo interpretation techniques. Using a one-acre resolution, the existing LU/LC and IS data were compared against the current digital imagery and analyzed for change. Polygon attributes and boundaries were revised to reflect current conditions using custom .NET tools developed by AIS programming staff. To enhance map accuracy, photo signatures that were difficult to identify were flagged for on-site visits performed by AIS field survey teams.
Concurrent with the 2002 LU/LC Update, NJDEP tasked AIS to create a detailed statewide hydrologic layer, with the intention of incorporating the data into the US Geological Survey (USGS) National Hydrologic Dataset (NHD) program. AIS utilized the same CIR imagery and computer interactive photo interpretation data capture methods employed for LU/LC interpretation. The resulting hydrologic dataset is so detailed that the existing NHD coding guidelines were not sufficient. NJDEP has subsequently been working with U.S.G.S. to develop new NHD coding guidelines to accommodate the additional information of NJDEP’s current hydrology layer.
To view the full state data visit the NJDEP website.