This is a MD iMAP hosted service layer. Find more information at http://imap.maryland.gov. The Maryland Department of Natural resources began updating the National Wetlands Inventory (NWI) mapping of wetlands in Maryland in the early 1990s. This database lists the 3.75' x 3.75' USGS quadrangles for which 'DNR Wetlands' have been mapped. It identifies the date of source photography used to map wetlands - and the status of mapping effort. This database also gives the five-letter abbreviation used for naming 'DNR_Wetlands' files. In most cases - the first five characters are the first 'five characters' of the 'USGS 7.5' Quad Name.' When completed - the series will provide coverage for the entire State of Maryland. Last Updated: Feature Service Layer Link: http://geodata.md.gov/imap/rest/services/Hydrology/MD_Wetlands/MapServer/0 ADDITIONAL LICENSE TERMS: The Spatial Data and the information therein (collectively "the Data") is provided "as is" without warranty of any kind either expressed implied or statutory. The user assumes the entire risk as to quality and performance of the Data. No guarantee of accuracy is granted nor is any responsibility for reliance thereon assumed. In no event shall the State of Maryland be liable for direct indirect incidental consequential or special damages of any kind. The State of Maryland does not accept liability for any damages or misrepresentation caused by inaccuracies in the Data or as a result to changes to the Data nor is there responsibility assumed to maintain the Data in any manner or form. The Data can be freely distributed as long as the metadata entry is not modified or deleted. Any data derived from the Data must acknowledge the State of Maryland in the metadata.

This is a MD iMAP hosted service layer. Find more information at http://imap.maryland.gov. This data set represents the extent - approximate location and type of wetlands and deepwater habitats in the conterminous United States. These data delineate the areal extent of wetlands and surface waters as defined by Cowardin et al. (1979). Certain wetland habitats are excluded from the National mapping program because of the limitations of aerial imagery as the primary data source used to detect wetlands. These habitats include seagrasses or submerged aquatic vegetation that are found in the intertidal and subtidal zones of estuaries and near shore coastal waters. Some deepwater reef communities (coral or tuberficid worm reefs) have also been excluded from the inventory. These habitats - because of their depth - go undetected by aerial imagery. By policy - the Service also excludes certain types of farmed wetlands"" as may be defined by the Food Security Act or that do not coincide with the Cowardin et al. definition. Contact the Service's Regional Wetland Coordinator for additional information on what types of farmed wetlands are included on wetland maps. Last Updated: Feature Service Layer Link: http://geodata.md.gov/imap/rest/services/Hydrology/MD_Wetlands/MapServer/2 ADDITIONAL LICENSE TERMS: The Spatial Data and the information therein (collectively the ""Data"") is provided "as is" without warranty of any kind either expressed implied or statutory. The user assumes the entire risk as to quality and performance of the Data. No guarantee of accuracy is granted nor is any responsibility for reliance thereon assumed. In no event shall the State of Maryland be liable for direct indirect incidental consequential or special damages of any kind. The State of Maryland does not accept liability for any damages or misrepresentation caused by inaccuracies in the Data or as a result to changes to the Data nor is there responsibility assumed to maintain the Data in any manner or form. The Data can be freely distributed as long as the metadata entry is not modified or deleted. Any data derived from the Data must acknowledge the State of Maryland in the metadata.

This is a MD iMAP hosted service layer. Find more information at http://imap.maryland.gov. In Maryland certain wetlands with rare - threatened - endangered species or unique habitat receive special attention. The Code of Maryland Regulations (COMAR) Title 26 - Subtitle 23 - Chapter 06 - Sections 01 & 02 identifies these Wetlands of Special State Concern (WSSC) and affords them certain protections including a 100 foot buffer from development. The Maryland Department of the Environment is responsible for identifying and regulating these wetlands. In general - the US Fish and Wildlife Service's National Wetlands Inventory wetlands provide the basis for identifying these special wetlands. Additional information - determined from field inspections - is used to identify and classify these areas. Last Updated: Feature Service Layer Link: http://geodata.md.gov/imap/rest/services/Hydrology/MD_Wetlands/MapServer/3 ADDITIONAL LICENSE TERMS: The Spatial Data and the information therein (collectively "the Data") is provided "as is" without warranty of any kind either expressed implied or statutory. The user assumes the entire risk as to quality and performance of the Data. No guarantee of accuracy is granted nor is any responsibility for reliance thereon assumed. In no event shall the State of Maryland be liable for direct indirect incidental consequential or special damages of any kind. The State of Maryland does not accept liability for any damages or misrepresentation caused by inaccuracies in the Data or as a result to changes to the Data nor is there responsibility assumed to maintain the Data in any manner or form. The Data can be freely distributed as long as the metadata entry is not modified or deleted. Any data derived from the Data must acknowledge the State of Maryland in the metadata.

This is a MD iMAP hosted service layer. Find more information at http://imap.maryland.gov. In Maryland certain wetlands with rare - threatened - endangered species or unique habitat receive special attention. The Code of Maryland Regulations (COMAR) Title 26 - Subtitle 23 - Chapter 06 - Sections 01 & 02 identifies these Wetlands of Special State Concern (WSSC) and affords them certain protections including a 100 foot buffer from development. The Maryland Department of the Environment is responsible for identifying and regulating these wetlands. In general - the US Fish and Wildlife Service's National Wetlands Inventory wetlands provide the basis for identifying these special wetlands. Additional information - determined from field inspections - is used to identify and classify these areas.The Department of Natural Resources makes no warranty - expressed or implied - as to the use or appropriateness of Spatial Data - and there are no warranties of merchantability or fitness for a particular purpose or use. The information contained in Spatial Data is from publicly available sources - but no representation is made as to the accuracy or completeness of Spatial Data. The Department of Natural Resources shall not be subject to liability for human error - error due to software conversion - defect - or failure of machines - or any material used in the connection with the machines - including tapes - disks - CD-ROMs or DVD-ROMs and energy. The Department of Natural Resources shall not be liable for any lost profits - consequential damages - or claims against the Department of Natural Resources by third parties. The liability of the Department of Natural Resources for damage regardless of the form of the action shall not exceed any distribution fees that may have been paid in obtaining Spatial Data. Last Updated: Feature Service Layer Link: http://geodata.md.gov/imap/rest/services/Hydrology/MD_Wetlands/MapServer/4 ADDITIONAL LICENSE TERMS: The Spatial Data and the information therein (collectively "the Data") is provided "as is" without warranty of any kind either expressed implied or statutory. The user assumes the entire risk as to quality and performance of the Data. No guarantee of accuracy is granted nor is any responsibility for reliance thereon assumed. In no event shall the State of Maryland be liable for direct indirect incidental consequential or special damages of any kind. The State of Maryland does not accept liability for any damages or misrepresentation caused by inaccuracies in the Data or as a result to changes to the Data nor is there responsibility assumed to maintain the Data in any manner or form. The Data can be freely distributed as long as the metadata entry is not modified or deleted. Any data derived from the Data must acknowledge the State of Maryland in the metadata.

This is a MD iMAP hosted service layer. Find more information at http://imap.maryland.gov. The Maryland coastal zone is comprised of the land - water and subaqueous land between the territorial limits of Maryland in the Chesapeake Bay - Atlantic Coastal Bays and the Atlantic Ocean - as well as the towns - cities and counties that contain and help govern the thousands of miles of Maryland shoreline. The Maryland coastal zone extends from three miles out in the Atlantic Ocean to the inland boundaries of the 16 counties and Baltimore City that border the Atlantic Ocean - Chesapeake Bay and the Potomac River up to the District of Columbia. This area encompasses two-thirds of the State s land area and is home to almost 70% of Maryland's residents. Feature Service Layer Link: http://geodata.md.gov/imap/rest/services/Hydrology/MD_Watersheds/FeatureServer/4 ADDITIONAL LICENSE TERMS: The Spatial Data and the information therein (collectively "the Data") is provided "as is" without warranty of any kind either expressed implied or statutory. The user assumes the entire risk as to quality and performance of the Data. No guarantee of accuracy is granted nor is any responsibility for reliance thereon assumed. In no event shall the State of Maryland be liable for direct indirect incidental consequential or special damages of any kind. The State of Maryland does not accept liability for any damages or misrepresentation caused by inaccuracies in the Data or as a result to changes to the Data nor is there responsibility assumed to maintain the Data in any manner or form. The Data can be freely distributed as long as the metadata entry is not modified or deleted. Any data derived from the Data must acknowledge the State of Maryland in the metadata.

This is a MD iMAP hosted service layer. Find more information at http://imap.maryland.gov. Line features of rivers and streams (detailed shape) in Maryland. Last Updated: Feature Service Layer Link: http://geodata.md.gov/imap/rest/services/Hydrology/MD_Waterbodies/MapServer/2 ADDITIONAL LICENSE TERMS: The Spatial Data and the information therein (collectively "the Data") is provided "as is" without warranty of any kind either expressed implied or statutory. The user assumes the entire risk as to quality and performance of the Data. No guarantee of accuracy is granted nor is any responsibility for reliance thereon assumed. In no event shall the State of Maryland be liable for direct indirect incidental consequential or special damages of any kind. The State of Maryland does not accept liability for any damages or misrepresentation caused by inaccuracies in the Data or as a result to changes to the Data nor is there responsibility assumed to maintain the Data in any manner or form. The Data can be freely distributed as long as the metadata entry is not modified or deleted. Any data derived from the Data must acknowledge the State of Maryland in the metadata.

This is a MD iMAP hosted service layer. Find more information at http://imap.maryland.gov. The digital segmented network based on watershed boundaries - ERF1-2 - includes enhancements to the U.S. Environmental Protection Agency's River Reach File 1 (RF1) (USEPA - 1996; DeWald and others - 1985) to support national and regional-scale surface water-quality modeling. Alexander and others (1999) developed ERF1 - which assessed the hydrologic integrity of the digital reach traces and calculated the mean water time-of-travel in river reaches and reservoirs. ERF1-2 serves as the foundation for SPARROW (Spatially Referenced Regressions (of nutrient transport) On Watershed) modeling. Within the context of a Geographic Information System - SPARROW estimates the proportion of watersheds in the conterminous U.S. with outflow concentrations of several nutrients - including total nitrogen and total phosphorus - (Smith - R.A. - Schwarz - G.E. - and Alexander - R.B. - 1997). This version of the network expands on ERF1 (version 1.2; Alexander et al. 1999) - and includes the incremental and total drainage area derived from 1-kilometer (km) elevation data for North America. Previous estimates of the water time-of-travel were recomputed for reaches with water- quality monitoring sites that included two reaches. The mean flow and velocity estimates for these split reaches are based on previous estimation methods (Alexander et al. - 1999) and are unchanged in ERF1-2. Drainage area calculations provide data used to estimate the contribution of a given nutrient to the outflow. Data estimates depend on the accuracy of node connectivity. Reaches split at water- quality or pesticide-monitoring sites indicate the source point for estimating the contribution and transport of nutrients and their loads throughout the watersheds. The ERF1-2 coverage extends the earlier ERF1 coverage by providing digital-elevation-model (DEM-based estimates of reach drainage area founded on the 1-kilometer data for North America (Verdin - 1996; Verdin and Jenson - 1996). A 1-kilometer raster grid of ERF1-2 projected to Lambert Azimuthal Equal Area - NAD 27 Datum (Snyder - 1987) - was merged with the HYDRO1K flow direction data set (Verdin and Jenson - 1996) to generate a DEM-based watershed grid - ERF1_2WS. The watershed boundaries are maintained in a raster (grid cell) format as well as a vector (polygon) format for subsequent model analysis. Both the coverage - ERF1-2 - and the grid - ERF1-2WS are available at: http://water.usgs.gov/lookup/gisgetlist. The version of RF1 used to compile ERF1-2 was an early edition of a USGS RF1 translation and was updated by USEPA (USEPA - 1996). The capabilities of the enhanced version of RF1 (ERF1-2) and the current USEPA version have not been evaluated. The user is referred to the USEPA version [http://www.epa.gov/owow/monitoring/rf/rfindex] for discussions of streamflow accuracy and general background on the origin of RF1. Last Updated: Feature Service Layer Link: http://geodata.md.gov/imap/rest/services/Hydrology/MD_Waterbodies/MapServer/0 ADDITIONAL LICENSE TERMS: The Spatial Data and the information therein (collectively "the Data") is provided "as is" without warranty of any kind either expressed implied or statutory. The user assumes the entire risk as to quality and performance of the Data. No guarantee of accuracy is granted nor is any responsibility for reliance thereon assumed. In no event shall the State of Maryland be liable for direct indirect incidental consequential or special damages of any kind. The State of Maryland does not accept liability for any damages or misrepresentation caused by inaccuracies in the Data or as a result to changes to the Data nor is there responsibility assumed to maintain the Data in any manner or form. The Data can be freely distributed as long as the metadata entry is not modified or deleted. Any data derived from the Data must acknowledge the State of Maryland in th

This is a MD iMAP hosted service layer. Find more information at http://imap.maryland.gov. Although the State of Maryland has no natural lakes - it has an abundance of created lakes and ponds that are used for wildlife habitat - recreation - water supply - and other reasons. This digital file shows the locations of the largest and most significant lakes - as well as some of the smaller lakes and ponds in the state. Most of the digitized lakes and ponds are greater than 2 acres. Last Updated: Feature Service Layer Link: http://geodata.md.gov/imap/rest/services/Hydrology/MD_Waterbodies/MapServer/3 ADDITIONAL LICENSE TERMS: The Spatial Data and the information therein (collectively "the Data") is provided "as is" without warranty of any kind either expressed implied or statutory. The user assumes the entire risk as to quality and performance of the Data. No guarantee of accuracy is granted nor is any responsibility for reliance thereon assumed. In no event shall the State of Maryland be liable for direct indirect incidental consequential or special damages of any kind. The State of Maryland does not accept liability for any damages or misrepresentation caused by inaccuracies in the Data or as a result to changes to the Data nor is there responsibility assumed to maintain the Data in any manner or form. The Data can be freely distributed as long as the metadata entry is not modified or deleted. Any data derived from the Data must acknowledge the State of Maryland in the metadata.

This is a MD iMAP hosted service layer. Find more information at http://imap.maryland.gov. Maryland Tributary Teams-comprised of local citizens - farmers - business leaders and government officials appointed by the Governor-are working to keep local waterways clean and healthy. TheTributary Team jurisdictions were determined from the watershed boundaries that were developed in a joint state and federal effort to create a consistent watershed file for use by all government agencies with an interest in Maryland's watersheds. Feature Service Layer Link: http://geodata.md.gov/imap/rest/services/Hydrology/MD_Watersheds/FeatureServer/5 ADDITIONAL LICENSE TERMS: The Spatial Data and the information therein (collectively "the Data") is provided "as is" without warranty of any kind either expressed implied or statutory. The user assumes the entire risk as to quality and performance of the Data. No guarantee of accuracy is granted nor is any responsibility for reliance thereon assumed. In no event shall the State of Maryland be liable for direct indirect incidental consequential or special damages of any kind. The State of Maryland does not accept liability for any damages or misrepresentation caused by inaccuracies in the Data or as a result to changes to the Data nor is there responsibility assumed to maintain the Data in any manner or form. The Data can be freely distributed as long as the metadata entry is not modified or deleted. Any data derived from the Data must acknowledge the State of Maryland in the metadata.

This is a MD iMAP hosted service layer. Find more information at http://imap.maryland.gov. Hydrologic unit boundaries define the aerial extent of surface water drainage to a point. Hydrologic units through four levels were created in the 1970's and have been used extensively throughout the United States. During that time the U.S. Geological Survey (USGS) developed a hierarchical hydrologic unit code (HUC) for Hydrologic unit boundaries define the aerial extent of surface water drainage to a point. Hydrologic units through four levels were created in the 1970's and have been used extensively throughout the United States. During that time the U.S. Geological Survey (USGS) developed a hierarchical hydrologic unit code (HUC) for the United States. This system divides the country into 21 Regions - 222 Subregions - 352 Accounting Units - and 2 - 149 Cataloging Units based on surface hydrologic features. The smallest USGS unit (8-digit HU) is approximately 448 - 000 acres. During the late 1970's the Natural Resources Conservation Service (NRCS) - formerly the Soil Conservation Service - initiated a national program to further subdivide HU's into smaller watersheds for water resources planning. A 3-digit extension was added to the 8-digit identification. By the early 1980's this 11-digit HU mapping was completed for most of the U.S. These data demonstrate Maryland's watersheds as represented by the federal Hydrologic Unit Code denoted by an 11-digit numerical code. The watersheds were defined using contours on U.S. Geological Survey (USGS) 7.5 minute quadrangle map sheets. The state has been divided into 138 watersheds that are identified by Maryland - using an 8-digit numerical code. These watersheds are equivalent to the HUC 11-digit codes. The watershed file is generally considered to be map accurate at a scale of 1:24 - 000. A new 12-digit watershed file is available from DNR which provides more detailed line work for over 1 - 100 watersheds which is approximately equivalent to the HUC 14-digit code. Feature Service Layer Link: http://geodata.md.gov/imap/rest/services/Hydrology/MD_Watersheds/FeatureServer/0 ADDITIONAL LICENSE TERMS: The Spatial Data and the information therein (collectively "the Data") is provided "as is" without warranty of any kind either expressed implied or statutory. The user assumes the entire risk as to quality and performance of the Data. No guarantee of accuracy is granted nor is any responsibility for reliance thereon assumed. In no event shall the State of Maryland be liable for direct indirect incidental consequential or special damages of any kind. The State of Maryland does not accept liability for any damages or misrepresentation caused by inaccuracies in the Data or as a result to changes to the Data nor is there responsibility assumed to maintain the Data in any manner or form. The Data can be freely distributed as long as the metadata entry is not modified or deleted. Any data derived from the Data must acknowledge the State of Maryland in the metadata.