Water Quality Maps

Maps provide a unique way to explore a particular topic. The maps in this gallery were developed by the Department for use in Water Quality P​rotection, Restora​tion and Advisories.

Shellfish Harvesting and Closure AreasShellfish Harvesting and Closure Areas
The map generally depicts the classification of shellfish waters of the State: restricted, conditionally approved, or approved.

Maryland's Current Shellfish AdvisoriesMaryland's Current Shellfish Advisories
Use this map to view Maryland's up-to-date shellfish harvesting advisories for conditionally approved waters.

Maryland Healthy BeachesMaryland Healthy Beaches
Use this interactive map to find the current conditions at your favorite beaches.

Designated Use ClassificationsDesignated Use Classifications
This map displays the designated use classes assigned to Maryland's surface waters as promulgated in Code of Maryland Regulations Section Maryland classifies surface water bodies according to use classes which describe the suite of specific designated uses for that water body.

Water Quality AssessmentsWater Quality Assessments
This interactive map displays surface water quality assessment information found in Maryland’s 2018 Integrated Report of Surface Water Quality (IR).  Assessments have been made for a variety of water body types and show both good water quality and impairments.​

Maryland's Tier II High Quality WatersMaryland's Tier II High Quality Waters
This map displays Maryland's Tier II high quality stream segments and their drainage areas/catchments.

Maryland's Tier II High Quality WatersMaryland's Tier II Waters Story Map
This interactive story map provides an introduction to Maryland's Tier II waters which are the designated high quality streams and their watersheds, through text, maps, photos, and diagrams.

These maps display watersheds where TMDLs have been developed.

Md's 8-Digit Watershed MapsMaryland's 8-Digit Watershed Maps
This map displays Maryland's Watershed Maps.

MD 319(h) Program ProjectsMaryland 319(h) Program Projects
Learn how Maryland is reducing nonpoint source pollution with an interactive application highlighting Maryland’s 319(h) Nonpoint Source Program under the Clean Water Act. Navigate the story map to learn more about 319(h) funded projects that provide measurable improvements in water quality and habitat.

Road Salt in MDRoad Salt in Maryland Story Map
View this storymap to learn how the excessive use of road salt is affecting you. For more information check the page on road salt

Stormwater graphicStormwaterPrint
StormwaterPrint is a Geographic Information System (GIS) application developed by the Maryland Department of the Environment (MDE) in support of the MD iMap initiative. It highlights the efforts being undertaken by the State and county and municipal stormwater management programs to control urban water pollution. The aim is to provide planners, government authorities, and the public with critical data and analyses that will help with decision-making and provide public outreach.