This dataset depicts TMDL watershed boundaries. A TMDL watershed is the area covered by a TMDL equation. It consists of one or more impaired streams that have an assigned Cause Group Code (CGC). The CGC is the link between the TMDL and the Assessment Report. The TMDL equations are stored in a table in the TMDL database. Currently, the database contains about 650 equations, which are set across the entire state. Each equation includes the Waste Load Allocation (WLA), which is the portion of the TMDL that accounts for pollution from point sources (permits). The WLA cannot be exceeded during permit reissuance or its TMDL equation must be modified.

The Virginia Water Protection Program (VWP) regulates activities in all surface waters which includes wetlands, streams, and open water. A permit (general permit coverage or individual permit) may be required in accordance with program regulations and State Water Control Law. This layer represents the project boundaries of both active and historic VWP General Permits and VWP Individual Permits for the state. The VWP permit's number, name, and regional office are among several attributes in this layer. The permit boundaries are drawn to represent the project boundary map provided by the permittee. The GIS data layers and maps produced by the Virginia Department of Environmental Quality (DEQ) are provided as a public resource. The Virginia Department of Environmental Quality has attempted to ensure the accuracy and completeness of the data. DEQ makes or extends no warranties of any type, expressed or implied, including but not limited to: appropriateness of use, accuracy, or completeness of data.
DEQ does not guarantee the GIS data provided is complete or current because the information contained in these data may change over time. These data and related maps are not legal documents and should not be construed or used as such. It is encouraged that these data are obtained from a DEQ resource and not through other sources which may lead to changed or outdated data. While using DEQ GIS data, the use and modification of such data is done at the risk of the user, and where DEQ holds no liability of any nature resulting from the use or correctness of this data.
Pursuant to Section 54.1-402, paragraph C of the Code of Virginia, this data may not be used for purposes listed in said paragraph C, since the data was not created, nor is it maintained under the supervision of a licensed land surveyor.

Links to the page of data assets pertaining to water resources in Virginia

Polygon layer showing the boundaries of Virginia Soil and Water Conservation Districts within the Commonwealth of Virginia.

Water quality monitoring stations and parameters to be sampled during the calendar year.

The Virginia Water Protection Program (VWP) regulates activities in all surface waters which includes wetlands, streams, and open water. A permit (general permit coverage or individual permit) may be required in accordance with program regulations and State Water Control Law. This layer represents the Permittee Responsible Mitigation Area (PRMA) boundaries which certain VWP Permits require as part of their permit's compensation plan. The VWP permit's number, name, and regional office are among several attributes in this layer. The PRMA boundaries are drawn to represent the project's mitigation area boundary which is usually onsite of the VWP project. The GIS data layers and maps produced by the Virginia Department of Environmental Quality (DEQ) are provided as a public resource. The Virginia Department of Environmental Quality has attempted to ensure the accuracy and completeness of the data. DEQ makes or extends no warranties of any type, expressed or implied, including but not limited to: appropriateness of use, accuracy, or completeness of data.
DEQ does not guarantee the GIS data provided is complete or current because the information contained in these data may change over time. These data and related maps are not legal documents and should not be construed or used as such. It is encouraged that these data are obtained from a DEQ resource and not through other sources which may lead to changed or outdated data. While using DEQ GIS data, the use and modification of such data is done at the risk of the user, and where DEQ holds no liability of any nature resulting from the use or correctness of this data.
Pursuant to Section 54.1-402, paragraph C of the Code of Virginia, this data may not be used for purposes listed in said paragraph C, since the data was not created, nor is it maintained under the supervision of a licensed land surveyor.

The Virginia Water Protection Program (VWP) regulates activities in all surface waters which includes wetlands, streams, and open water. A permit (general permit coverage or individual permit) may be required in accordance with program regulations and State Water Control Law. This layer represents the project location of both active and historic VWP General Permit Coverage (GP) issued across the state. The General Permit Tracking number, name, and regional office are among several attributes in this layer. The attribute data is pulled from DEQ's Comprehensive Environmental Data System (CEDS). The GIS data layers and maps produced by the Virginia Department of Environmental Quality (DEQ) are provided as a public resource. The Virginia Department of Environmental Quality has attempted to ensure the accuracy and completeness of the data. DEQ makes or extends no warranties of any type, expressed or implied, including but not limited to: appropriateness of use, accuracy, or completeness of data.
DEQ does not guarantee the GIS data provided is complete or current because the information contained in these data may change over time. These data and related maps are not legal documents and should not be construed or used as such. It is encouraged that these data are obtained from a DEQ resource and not through other sources which may lead to changed or outdated data. While using DEQ GIS data, the use and modification of such data is done at the risk of the user, and where DEQ holds no liability of any nature resulting from the use or correctness of this data.
Pursuant to Section 54.1-402, paragraph C of the Code of Virginia, this data may not be used for purposes listed in said paragraph C, since the data was not created, nor is it maintained under the supervision of a licensed land surveyor.