Keywords
Theme:
Strahler, Tributary Strategy, Federal Information Processing Standard, FIPS, Watersheds, Maryland watershed codes, Third-Order streams, Hydrologic Unit Codes, Drainage Area, USGS 7.5' Quadrangle, Topography
Place:
Maryland, Prince George's County
Description
Abstract
This file is a statewide digital watershed file. It was created primarily for state and federal agency use. The watersheds define Strahler (Strahler 1952 p. 1120) third order stream drainage by contours on U.S. Geological Survey (USGS) 7.5 minute quadrangle map sheets. Some watersheds drainage areas were defined for streams less than third order and some large area watershed were split to maintain a maximum size of 15,000 acres. The watershed boundaries in this file 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. The U.S. Natural Resources Conservation Service (NRCS) redefined the third order watersheds creating the HUA14 file. This file contains all of the HUA14 watersheds and some added watersheds to maintain water quality sampling sites. It was also used to create the Maryland Sub-Watershed file.
Purpose
This file was created to identify and define third order watershed from contours on the U.S. Geological Survey (USGS) 7.5 minute quadrangle map sheets. In addition to identifying Strahler third order streams it was necessary to separate certain streams to ensure their association with a proper receiving body of water. Some watersheds were split to maintain the size of watershed areas for state planning purposes. It was intended to maintain a unique watershed number in both this file and HUA14 so that state and federal agencies would have a consistent code for reference. This file has both the federal codes and the state codes for cross referencing. Most of the watersheds in this file are the same as the watershed boundaries in the federal file HUA14. There is one difference in the watershed files. This file has a buffered shoreline added to separate the Chesapeake Bay from land. The parent federal file HUA14 identifies watersheds by the federal Hydrologic Unit Code (HUA or HUC code) while the state file uses the Maryland Department of the Environment (MDE) watershed codes.
Supplementary Information
See Maryland's Sub-Watershed which is an 8-digit watershed file and its metadata. The State political boundary in this file is used for all Statewide files created by the Geographic Information Services Division of MD DNR. HUA14 Watershed codes are in the file. MDE collects data to the MDE8DIGT code. MD DNR maintains data for the 10 Tributary Strategy Watersheds in the STRACODE and STRANAME field. This file is derived from SHED1998.
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Status of the data
Complete
Data update frequency:
As needed
Time period for which the data is relevant
Date and time:
19970201 at time 000000
Description:
Publication date
Publication Information
Who created the data: Maryland Department of Natural Resources, Ken Miller, Chief. Spatial Data Production Services
Date and time:
19980101 at time 000000
Contact
Name:
GIS Supervisor
Title:
GIS Supervisor
Organization:
The Maryland-National Capital Park & Planning Commission - Prince George's County
Phone:
(301) 952-3108
email:
**NO_SPAM**ppd-gis@ppd.mncppc.org
Hours of Operation:
9AM - 5PM
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Constraints on accessing and using the data
Access constraints:
See http://www.mncppc.org/html/gismaps.htm#price
Use constraints:
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-ROM’s or DVD-ROM’s 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.
Details about this document
Contents last updated: 20140225
Contents last reviewed: As needed
Who completed this document
GIS Coordinator
The Maryland-National Capital Park & Planning Commission
mailing:
14741 Governor Oden Bowie Drive
Upper Marlboro, Maryland 20772
US
(301) 952-4779 (voice)
(301) 952-3459 (fax)
**NO_SPAM**ppd-gis@ppd.mncppc.org
Hours of service:
9AM - 5PM
Standards used to create this document
Standard name: FGDC Content Standard for Digital Geospatial Metadata
Standard version: FGDC-STD-001-1998
Time convention used in this document: local time
Horizontal coordinate system
Details
Map Projection Name: NAD 1983 StatePlane Maryland FIPS 1900 Feet
Standard Parallel: 38.3
Standard Parallel: 39.45
Longitude of Central Meridian: -77.0
Latitude of Projection Origin: 37.66666666666666
False Easting: 1312333.333333333
False Northing: 0.0
Planar Coordinate Information
Planar Distance Units: Foot_US
Coordinate Encoding Method: coordinate pair
Coordinate Representation
Abscissa Resolution: 0.00025600000023841865
Ordinate Resolution: 0.00025600000023841865
Geodetic Model
Horizontal Datum Name: D North American 1983
Ellipsoid Name: GRS 1980
Semi-major Axis: 6378137.0
Denominator of Flattening Ratio: 298.257222101
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Bounding coordinates
Horizontal
In decimal degrees
West:
-77.077197
East:
-76.668433
North:
39.130714
South:
38.540697
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Lineage
Feature and Attribute Updates
Update 1
Edit Description: Creation of hardcopy of Maryland watershed maps for planning - MDE - 1960's - 1:62,500 watershed maps were created from county topographic maps produced in the 1960's. These hardcopy maps were used by hydrologists and planners to create the first statewide Watershed maps. The Watersheds were attributed with a Maryland Department of the Environment (MDE) 8 digit code. MDE is the custodian of these hard copy maps.
Date Updated: 19600101
Who did this process
Ken Miller
Maryland Department of Natural Resources
Update 2
Edit Description: Creation of hardcopy of Federal watershed maps for planning - NRCS - 1960's - Process - manual cartographic interpretation. During this era the U.S. Natural Resource Conservation Service (NRCS) created hardcopy Watershed 100,000 scale state wide map attributed with the Hydrologic Unit Code (HUA or HUC).
Date Updated: 19600101
Update 3
Edit Description: Creation of digital Maryland watershed file (SWSHED) - MOP - Process - manual cartographic interpretation. The Watersheds in both maps were for groupings of large rivers. These groupings were hydrologically correct but not the same. Daft, McCune and Walker, working under contract with the Maryland Office of Planning (OP), digitized the MDE Watershed maps. The contract specified delineation of Watersheds for third order streams using hard copy USGS 7.5 minute quadrangle map sheets as a basis for contour lines. This file was completed in 1994. OP is the custodian of this original digital Watershed file. Projection State Plane 27 feet.
Date Updated: 19940101
Update 4
Edit Description: Combining Maryland and Federal watersheds to create a digital file - NRCS - Process - digitization from hard copy maps into ARC/INFO. This file defines third order Watersheds correctly, although it has tidal areas that were too large to use in Watershed planning. State and federal agencies formed a work group to define Watersheds of consistent size for planning purposes. The NRCS was given directions to define smaller Watersheds and create a digital file. NRCS added the line work to the Maryland file over USGS quad sheets. Projection converted to UTM zone 17 meters.
Date Updated: 19950101
Update 5
Edit Description: QC digital watershed file - DNR - Process - digitization from hard copy maps into GRASS. QC was done on this file over USGS quad sheets and it was determined that some of the lines were not quad accurate. DNR reviewed each of the Watersheds and coordinated with NRCS to make the changes; projection converted to State Plane 27 feet
Date Updated: 19960101
Update 6
Edit Description: Create digital file DNRHUA14 - DNR - process: on screen review over scanned USGS 7.5 minute quad sheets in Micro Images, Inc. TNTMIPS. This file had no attributes. A unique four digit number was added to each polygon for identification. Each member of the work group was given this file (DNRHUA14) as a beta release with hopes that no new Watershed would need to be defined; projection State Plane 27 feet.
Date Updated: 19960101
Update 7
Edit Description: Attribute DNRHUA14 - DNR - process: create a field and fill with a unique number. This was done in ARC/INFO. DNR began attributing the file DNRHUA14 with MDE codes. Pennsylvania and Virginia began digitizing Watersheds for their state. They used DNRHUA14 to edge match between states. Some of the Watersheds could be better defined using elevation from the adjoining state. Some of the MDE codes could not be maintained because lines were missing; projection State Plane 27 feet. Process was visual interpretation.
Date Updated: 19960101
Update 8
Edit Description: Add lines to maintain MDE codes and to be consistent with adjoining states - DNR - process: visual interpretation. DNR coordinated with NRCS to add the appropriate lines from other states. NRCS does not maintain all-water polygons (Maryland does) so it was necessary to create two files: one with the all-water Watersheds (SHED1997) and one without (HUA14). DNR discovered that the state line in DNRHUA14 was a 250,000 scale line that had an error. DNR removed this line and merged in the State Highway Administration (SHA) 24,000 scale state line. DNR completed the line work that would be maintained in the federal file and sent the file to NRCS for QC review. Exported file to DLG format in UTM zone 17. DNR completed the line work that would be maintained by Maryland; projection DNR's file State Plane 27 feet, NRCS's file UTM zone 17 meters.
Date Updated: 19960101
Update 9
Edit Description: Create digital file SHED96A - DNR - Process was heads up digitizing in Micro Images Inc. TNTMIPS and attribution done in ARC/INFO. DNR released SUBS96A, a draft file. This file contained the MDE codes and the line work to be maintained by Maryland; projection State Plane 27 feet.
Date Updated: 19960101
Update 10
Edit Description: Remove dangles and overshoots in SHED96A - DNR - Users reported dangles and overshoots in the file. DNR cleaned the file. Process was done in ARC/INFO; projection State Plane 27 feet.
Date Updated: 19960101
Update 11
Edit Description: Create digital file SHED96B - DNR - DNR released SUBS96B, a draft file. This file is a cleaned version of the SUBS96A Watershed file. Projection State Plane 27 feet.
Date Updated: 19960101
Update 12
Edit Description: QC SHED96A - NRCS - NRCS reviewed the line work and determined that the lines were generalized; projection UTM Zone 17 meters. Process was to digitally compare the file to DNRHUA14 file in GRASS software package.
Date Updated: 19960101
Update 13
Edit Description: Correct the generalization of line work in SHED96A - NRCS - Process was to digitally compare the file to DNRHUA14 file in GRASS. NRCS re-digitized the lines (see event 8). NRCS digitized lines to be consistent with adjoining states and 250,000 scale state boundary; projection still UTM Zone 17 meters; digitizing - in GRASS.
Date Updated: 19960101
Update 14
Edit Description: Create digital files HUA14, HUA11, and HUA8 - NRCS - NRCS released HUA14 in a DLG format; projection UTM Zone 17 meters.
Date Updated: 19970101
Update 15
Edit Description: Using HUA14 change state line and make edits for compliance with MDE code - DNR - DNR removed the state line from HUA14 and added the SHA state line. The all-water Watersheds needing to maintain MDE Watershed codes were added and the file was attributed. Projection converted from UTM Zone 17 meters to State Plane 27 feet.
Date Updated: 19970101
Update 16
Edit Description: Create digital file SHED1997 - DNR - Process -done in ARC/INFO. DNR completed Metadata and released SHED1998.
Date Updated: 19970101
Update 17
Edit Description: Dissolve SHED1997 to SUB Watersheds Maryland's original hardcopy 1:62,500. DNR dissolved SHED1998 to Sub-watersheds, completed Metadata and released SUB1998.
Date Updated: 19970101
Update 18
Edit Description: Fixed problems in SHED1997. Released as SHED1998. The file was projected to Maryland State Plane NAD 1983 with units in Meters. The format of the file was converted to ESRI shape file. This is the current format for distribution.
Date Updated: 19980101
Sources
Source 1:
Maryland 8-Digit Watershed designation
(Maryland 8-Digit Watershed designation)
Media: None
Scale denominator: 62500
Contribution: 1:62,500 watershed maps were created from county topographic maps produced in the 1960's. These hardcopy maps were used by hydrologists and planners to create the first statewide watershed maps. The watersheds were attributed with a Maryland Department of the Environment (MDE) 8 digit watershed code. MDE is the custodian of these hard copy maps. Process - manual cartographic interpretation.
Source 2:
Hydrological Units map
(Hydrological Units map)
Media: None
Scale denominator: 100000
Contribution: During this era the U.S. Natural Resource Conservation Service (NRCS) created hardcopy watershed maps for 100,000 scale statewide map attributed with the Hydrologic Unit Code (HUA or HUC). Process - manual cartographic interpretation.
Source 3:
Digitized MDE watersheds
(Digitized MDE watersheds)
Media: None
Scale denominator: 62500
Contribution: Daft McCune and Walker working under contract with the Maryland Office of Planning (OP) digitized the MDE watershed maps. The contract specified delineation of watersheds for third order streams using hard copy USGS 7.5 minute quadrangle map sheets as a basis for contour lines. This file was completed in 1994. OP is the custodian of this original digital watershed file. Projection State Plane 27 feet. Process - digitization from hard copy maps into ARC/INFO. This file defines third order watersheds correctly, although it has tidal areas that were too large to use in watershed planning. State and federal agencies formed a work group to define watersheds of consistent size for planning purposes.
Source 4:
Maryland 8-Digit Watershed designation
(Maryland 8-Digit Watershed designation)
Media: None
Scale denominator: 62500
Contribution: Watershed Designations.
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Spatial data description
Vector data information
SDTS description
Feature class: SDTS feature type, feature count
Feature class:
GT-polygon composed of chains, 83