This page provides links to online maps and GIS downloads to assist in implementing TMDLs. The resources below include maps of every approved TMDL (categorized by pollutant) as well as shapefiles relating to the implementation process. Two separate TMDL maps are provided for nitrogen, phosphorus and sediment; one map for those TMDLs that were developed by the state, and one map for those TMDLs which are part of the 2010 Chesapea​ke Bay TMDLs. The geodatabase with all of the pollutant map files is​ available here​.

TMDL Maps by Pollutant

  Bacteria  Low​ pH
​  Metals
  Polychlorinated Biphenyls (PCBs)   Pesticides
  Sediment​   Trash

Additional Geographic Resources for TMDL I​mplementation

Watershed Delineations

County Boundaries

Stormwater Delineations

  • Phase 6 - NPDES-Regulated Stormwater Systems (download​)
  • Phase 5 - NPDES-Regulated Stormwater Systems (info | download)

Land Cover

Other Mapping Resources

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