Tier II High Quality Waters Map

Please note that it may take several seconds for the map to fully load.


About the Map

The map above displays Maryland's Tier II high quality stream segments and their drainage areas/catchments. Streams and their catchments are symbolized as to whether assimilative capacity remains.

How to Use the Interactive Map

To navigate the interactive map, use your arrow to drag and pan. Click the plus and minus buttons to zoom in and out. You can also enter an address in the window (top right) to zoom to a location. Clicking on "Basemap" allows the user to change the background (e.g. aerial photography, topographic coverage, etc). Clicking a stream or catchment will display the Tier II segment or catchment information. This map is current and was most recently updated in November of 2016. This map will be updated on an as-needed basis as new information becomes available. Clicking on “View Larger Map” will take the user to a customizable map interface where additional layers may be added. 

GIS Download

Download Shapefiles

Users attempting to use these shapefiles must have ESRI's ArcGIS 9.3 or a later version installed on their computer. Users should always consult the metadata included with these shapefiles prior to using them. These shapefiles provide geospatial information for the Tier II high quality water segments found in COMAR as well as those high quality segments on the pending list of Tier II segments (which are also protected under Click "download" above for a zip file containing the following Tier II GIS files (updated as of November 2016):

  • Tier II Stream Segments
  • Tier II Catchments/Watersheds
  • Tier II Nested Catchments

To return to the main High Quality Waters (Tier II) page, click here.

Please direct any questions or comments concerning Maryland's Antidegradation program to Angel Valdez at Angel.Valdez@maryland.gov or 410-537-3606.​