The Single Line Hydrography Network (SLNET) contains all captured single line representations of hydrographic features. In addition, single line representations of polygonal features and single line arbitrary network connectors are in the file.

The Base Hydrography Single Line Hydrography Network (SLNET) is the Alberta Environment and Protected Areas base SLNET data set. It is an update of the Base Features Hydrography SLNET in Central and Southern Alberta using aerial imagery, digital elevation models (DEM's) and various sources of provincial base data. The dataset includes all captured single-line hydrographic features, as well as centerline representations of polygonal water features and arbitrary connectors that maintain network connectivity.