Connecticut Subregional Drainage Basin Town Union is 1:24,000-scale data that is the geographic combined union of subregional drainage basins and towns in Connecticut. It includes polygon features that define where the Connecticut Subregional Drainage Basin Poly and Connecticut Town Polygon layers intersect and overlap each other as well as where, out of state, they do not. The geographic area covered includes the Connecticut mainland and islands along the Connecticut coastline, the Connecticut portion of Long Island Sound, and adjacent land areas in Massachusetts, New York and Rhode Island. Data is compiled at 1:24,000 scale (1 inch = 2,000 feet). This is static information that is not updated. The total geographic area covered by all polygon features is 7,201.26 square miles, larger than the area covered by Connecticut. Polygon feature attributes include basin number and name, town number and name, and feature size in acres and square miles. Each polygon feature includes the 1-digit major (MBAS_NO), 2-digit regional (RBAS_NO), 4-digit subregional (SBAS_NO) drainage basin number, and the Connecticut Town number (TOWN_NO). Subregional drainage basins typically are located in more than one town and a town will include more than one basin. A polygon feature exists for each subregional basin - town occurrence. Polygon features with Connecticut Town number values of zero (0) are basin features that do not overlap a Connecticut town and are either located in Long Island Sound, Massachusetts, New York, or Rhode Island. Connecticut Subregional Drainage Basin Town Union is derived from the union of the geometry and attributes of the Connecticut Subregional Drainage Basins for Clipping and Connecticut Town Polygon feature classes.
These data are used for geoprocessing and analysis purposes, particularly when analyzing subregional drainage basins located both in Connecticut and outside of Connecticut along the state boundary. As with the Connecticut Subregional Drainage Basin Town Intersect feature class, these data function as a two-way index of basins and towns, identifying the towns each subregional drainage basin is located in as well as identifying the subregional drainage basins located in each town. This feature class, however, accounts for basin areas outside of Connecticut so basins along the state boundary can be analized relative to their occurence, location, and size both in and outside of Connecticut. A Connecticut town can be analyzed relative to basins, or a basin can be analyzed relative to towns and areas out of state. A polygon feature exists for each area where subregional basins and Connecticut towns occur. If a basin is located in two different parts of town, a polygon feature will exist for each. If a portion of a basin is located outside of Connecticut, a polygon feature also exists. Polygon feature size is available in square miles or acres so basin occurrence as a percent of town area can be determined. These data are intended for analysis with other digital data compiled at 1:24,000 scale or greater.
A standardized mapping of natural drainage basins in Connecticut was completed in 1981 by the Connecticut Department of Environmental Protection. This drainage basin system divided Connecticut into 8 major basins, 45 regional basins, 337 subregional basins, 2,898 local basins, and 7,067 small drainage basin areas. Major basins are subdivided into regional basins. Regional basins are subdivided into subregional basins. Subregional basins are subdivided into local basins. Local basins are subdivided into smaller drainage basin areas for impoundments and river reaches. A pair of 1:24,000-scale polygon and line feature classes is available for all basin levels. These data are named Connecticut Major Basins, Connecticut Regional Basins, Connecticut Subregional Basins, Connecticut Local Basins, and Connecticut Drainage Basins. Connecticut Drainage Basins includes the most detailed information upon which the other basin datasets are based. A hierarchical drainage basin number was assigned to uniquely identify drainage basin areas. Drainage basin areas are numbered sequentially beginning upstream and proceeding downstream. The first digit (column 1) identifies the major basin, the first two digits (columns 1-2) identify the regional basin, the first 4 digits (columns 1-4) identify the subregional basin, and the first seven digits (columns 1-7) identify the local basin. Below are examples of the hierarchical drainage basin numbers. Basin Numbers: 4 = Major drainage basin number, MBAS_NO (column 1) 43 = Regional drainage basin number, RBAS_NO (columns 1-2) 4302 = Subregional drainage basin number, SBAS_NO (columns 1-4) 4302-04 = Local drainage basin number, LBAS_NO (columns 1-7) 4302-04-1-R12 = Basin drainage identification number, BASIN_NO (columns 1-13) Stream Order (column 9): 4304-00-1 = Stream order value of 1 represents a headwater basin. 4304-00-2 = Stream order value > 1 denotes the complexity of the drainage basin morphology. Mapping Status Element (column 10): 4302-00-2- = Ending with minus sign (-) denotes detail mapping at 1:24,000 scale for entire basin. 4302-00-2+ = Ending with plus sign (+) denotes detailed mapping not performed at 1:24,000 scale for the entire drainage basin. The Stream Order value will not reflect the complexity of the drainage basin morphology. 4302-00-1* = Ending with asterisk sign (*) denotes a headwater basin containing a delineated impoundment into which a delineated drainage basin outlets. Reach-Impoundment Identifier (column11) and Number (column 12-13): 4302-00-1-L1 = The value for the Reach-Impoundment Identifier for an impounment basin is L (for lake). It is followed by the Reach-Impoundment Number (1). 4302-04-1-R12 = The value for the Reach-Impoundment Identifier for a stream reach basin is R (for reach). It is followed the Reach-Impoundment Number (12).
publication date
No restrictions or legal prerequisites for using the data. The data is suitable for use at appropriate scale, and is not intended for maps printed at scales greater or more detailed than 1:24,000 scale (1 inch = 2,000 feet). Although this data set has been used by the State of Connecticut, Department of Environmental Protection, no warranty, expressed or implied, is made by the State of Connecticut, Department of Environmental Protection as to the accuracy of the data and or related materials. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the State of Connecticut, Department of Environmental Protection in the use of these data or related materials. The user assumes the entire risk related to the use of these data. Once the data is distributed to the user, modifications made to the data by the user should be noted in the metadata. When printing this data on a map or using it in a software application, analysis, or report, please acknowledge the State of Connecticut, Department of Environmental Protection as the source for this information. For example, include the following data source description when this layer is used in analysis or when printed on a map: Basins - From the Subregional Drainage Basin Town Union layer, compiled and published by CT DEP. Source map scale is 1:24,000.
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Tom Nosal, State of Connecticut, Department of Environmental Protection, for the final compilation and delineation of 1:24,000-scale drainage basin boundaries, assignment of drainage basin numbers, and conversion to digitial format. Basin boundaries were manually delineated at 1:24,000-scale by visually interpreting the 10 feet contour elevation lines and waterbody features appearing on 1:24,000-scale 7.5 minute USGS topographic quadrangle maps for Connecticut published between 1969 and 1984. The metadata abstract includes a brief description of a drainage basin obtained from material written by Jim Murphy in an article entitled Reading the Landscape published in the Citizen's Bulletin, a CT DEP monthy magazine.
The primary data source for basin information in the Connecticut Subregional Drainage Basin Town Union feature class is the Connecticut Drainage Basins layer. The Connecticut Drainage Basins layer retains the feature types and information identified on the 1:24,000-scale compilation sheets for the Natural Drainage Basins in Connecticut map, McElroy, 1981. All attributes have valid values. Values are within defined domains. There are no duplicate LBASIN_NO values except where expected (see definition of LBASIN_NO attribute). The SBASIN_NO is derived from the first 4-digits of BASIN_NO so the accuracy of the SBASIN_NO is dependent on that for the BASIN_NO. For polygon features, the accuracy test for the BASIN_NO attribute values was conducted by visually comparing the basin number information depicted on the source Mylar overlays with 1:24,000-scale check plots or interactive displays of the digital data on a computer graphic system. These check plot maps and computer displays labeled polygon features with BASIN_NO values and differentiated line features based on DBARC_COD values for comparison with the original source Mylars. Subsequently, four additional fields (MBAS_NO, RBAS_NO, SBAS_NO, LBAS_NO) were added and populated based on the first, first 2, first 4, and first 7 columns of the BASIN_NO attribute. The MAJOR, REGIONAL, and SUBREGION attributes store drainage basin names based on MBAS_NO, RBAS_NO, SBAS_NO values, respectively. Basin names were attributed by joining basin name lookup tables to the polygon features base on MBAS_NO, RBAS_NO, SBAS_NO key values and populating the corresponding fields. These basin names are from the Natural Drainage Basins in Connecticut map, McElroy, 1981. The AREA_SQMI (area in square miles) and ACREAGE (area in acres) field were automatically calculated for each polygon feature based on computer generated feature area in square feet. The primary data source for the town attribute information is the Connecticut Town Poly feature class. Refer to this feature class metadata for town number and name attribute accuracy report information.
Polygon features conform to the following topological rules. Polygons are single part. There are no duplicate polygons. Polygons do not self overlap. Polygons do not overlap other polygons. Lines are single part. Line features conform to the following topological rules. There are no duplicate lines. Lines do not self overlap. Lines do not overlap other lines. Lines intersect only at nodes, and nodes anchor the ends of all lines. Lines do not overshoot or undershoot other lines they are supposed to meet and intersect. In general, there are no duplicate features, unresolved intersections, overshooting lines, open polygons, sliver polygons, or unlabeled (unattributed) polygons. The tests of logical consistency were performed by the State of Connecticut using ESRI ArcInfo software to maintain feature topology in ArcInfo coverage format. The data is topologically clean. The ArcInfo Clean function was repeatedly used following edits to verify topology and enforce a minimum distance between vertices of 4 feet (fuzzy tolerance) and a minimum allowed overshoot length of 0 feet (dangle length).
The data reflects the content of the data source, which is a set of 1:24,000 scale mylar sheets used to compile and publish the 1:125,000-scale Drainage Basins in Connecticut Map, McElroy, 1982. All major, regional, subregional, local and smaller basin divides were digitized from these 1:24,000-scale mylar compilation sheets. This data is not updated.
The horizontal positional accuracy of this data complies with the United States National Map Accuracy Standards for 1:24,000 scale maps. According to this standard, not more than 10 percent of the locations tested are to be in error by more than 1/50 inch (40 feet) measured on the publication scale of a USGS 7.5 minute topographic quadrangle map. Drainage basin boundaries were interpolated from 10 FT elevation contours and surface water body (hydrography) information published on a set of USGS 1:24,000-scale, 7.5-minute topographic quadrangle maps that cover the State of Connecticut. Natural drainage basin boundaries were manually delineated by interpolating elevation and water body information found on topographic quadrangle maps published by the USGS between 1962 and 1984.
Basins compiled on 1:24,000-scale 7.5 minute USGS quadrangle area mylar overlays.
Connecticut Drainage Basins is in ArcInfo Coverage format having both polygon and line features. The name of the ArcInfo Coverage is BASIN.
Connecticut Subregional Drainage Basins is in ArcInfo Coverage format having both polygon and line features. The name of the ArcInfo Coverage is SBASIN. These polygon and line feature data were subsequently converted to geodatabase feature format and named SUBREGIONAL_BASIN_POLY and SUBREGIONAL_BASIN_LINE, respectively.
A polygon feature-based layer that depicts the geographic area for the State of Connecticut as one polygon feature. Connecticut State Poly is in Geodatabase Feature Class format.
Connecticut Subregional Drainage Basins for Clipping originated from the Connecticut Subregional Drainage Basins Polygon feature class (SUBREGIONAL_BASIN_POLY)
A polygon feature-based layer that defines the geographic areas for the State of Connecticut and its counties and towns (municipalities) as depicted on the U.S. Geological Survey (USGS) 7.5 minute topographic quadrangle maps for the State of Connecticut. This layer only includes information for Connecticut. Connecticut_Town_Poly is in Geodatabase Feature Class format.
Feature digitizing and attribution (digitizing tablet method) - Using ESRI ArcInfo software, basin boundary line features were digitized by registering the individual compilation sheets to the digitizing tablet and using the crosshairs of the digitizer's mouse to manually capture the geometry (location) of features drafted on the map. The corners of the USGS 7.5 minute topographic quadrangle maps are used as registration points and are depicted on the source map. The source map was registered to the digitizing tablet by digitizing (entering) the locations of four quadrangle corner registration points shown on the map. ArcInfo software compared the values of the digitized coordinates with the actual (true) values for the quadrangle corner (tic) features. The Root Mean Square (RMS) error generated by the ArcInfo software indicated the amount of error involved in transforming coordinates from the registered map to the digital layer. RMS errors higher than 0.004 were not acceptable and required re-registering the source map by digitizing the tic locations again. With a correct registration, basins boundaries features were manually digitized off the source map. Where necessary, additional minor corrections (edits) to feature geometry were manually digitized on the screen (heads-up digitizing) at display scales greater than 1:24,000. Feature location and attribute accuracy was visually checked and inspected by symbolizing and labeling features according to attribute value on the computer screen and on hard copy paper maps, and comparing this information to the orginal source data. These check plot maps were printed at the same scale as the source maps in order to visually inspect digitizing quality and the assignment of attribute values. Individual quadrangle level basin boundary coverages were appended and edgematched along quadrangle boundaries to create a statewide layer in ArcInfo Coverage format having both polygon and line features. Polygon label points were created and assigned BASIN_NO values that uniquely identified each polygon feature. Most other related polygon and line feature attributes were assigned through automated procedures based on the format and hierarchical nature of the BASIN_NO value. Four additional fields (MBAS_NO, RBAS_NO, SBAS_NO, LBAS_NO) were added and populated based on the first, first 2, first 4, and first 7 columns of the BASIN_NO attribute. The MAJOR, REGIONAL, and SUBREGION attributes store drainage basin names based on MBAS_NO, RBAS_NO, SBAS_NO values, respectively. Basin names were attributed by joining basin name lookup tables to the polygon features base on MBAS_NO, RBAS_NO, SBAS_NO key values and populating the corresponding fields. These basin names are from the Natural Drainage Basins in Connecticut map, McElroy, 1981. The AREA_SQMI (area in square miles) and ACREAGE (area in acres) field were automatically calculated for each polygon feature based on computer generated feature area in square feet. The GAZRECNO attribute was manually assigned to each basin polygon feature. For line features, the DBARC_COD attribute was populated through a combination of automated and manual processes that compared the BASIN_NO attribute value of the polygon on each side of the line. For example, if the two polygons are in different major basins (MBAS_NO on the left <> MBAS_NO on the right), then the line feature represents a Major basin drainage divide and is assigned a DBARC_COD value of 1. If the left and right polygons are in the same Major basins but in different regional basins (RBAS_NO on the left <> RBAS_NO on the right), the line feature is a Regional basin drainage divide and is assigned a DBARC_COD value of 2, and so on. DIVIDE is the English language equivalent of (decodes) the DBARC_COD attribute value and was populated by joining a lookup table to the line features instead of manually attributing these values for each line feature. AV_LEGEND and IMS_LEGEND values were also attributed through table joins.
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Create Subregional Drainage Basins - Using ArcInfo Workstation software, removed the BASIN_NO and LBAS_NO polygon feature attributes, calculated the ACREAGE and AREA_SQMI polygon attributes to zero, and dissolved polygon features on the remaining SBAS_NO, RBAS_NO, MBAS_NO, SUBREGIONAL, REGIONAL, and MAJOR attribute values to create subregional drainage basin polygon features. Using the ArcInfo Dissolve command, this step merged the smaller basin polygons into the larger subregional basin polygon features. Line features were preserved as part of the dissolve process and were merged using the ArcInfo Unsplit command afterwards. The ACREAGE and AREA_SQMI attributes were recalculated based on the new feature geometry, and ArcInfo coveage topology was re-established with the Build command.
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Subregional Drainage Basin Polygon features along the Connecticut coastline were enlarged to extend beyond the Connecticut shoreline into Long Island Sound to the boundary between the State of Connectict and New York in Long Island Sound. This feature class is designed to be used as a Clip feature class to clip other point line and polygon features to the subregional drainage basin areas. This feature class differs from the Subregional Drainage Basin Polygon feature class in that features along the Connecticut coastline were enlarged to extend beyond the Connecticut shoreline to the boundary between the State of Connectict and New York in Long Island Sound. These modifications apply to the coastal subregional basins 2000, 5000, and 7000 where the basin boundary coresponding to the Connecticut shoreline was replaced with the CT-NY state boundary in Long Island Sounce. These basin areas were enlarged to ensure Clip input features located along and near both sides of the shoreline are included in the Clip output feature class and associated with a subregional coastal basin (e.g. 2000, 5000, or 7000). Input features that should be in these coastal basins may not be in the resulting Clip output feature class unless the Connecticut Subregional Drainage Basins for Clipping is used as the Clip feature class. Using the unmodified, original Connecticut Subregional Drainage Basin Polygon feature class as the Clip feature class may produce different results for basins 2000, 5000, and 7000. The data source for the CT-NY state boundary is the Connecticut State Poly feature class. Both data sources used - Subregional Drainage Basins and Connecticut State Poly - have a 1:24,000-scale source map scale.
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Create Subregional Drainage Basin Town Union - Using a copy of the Connecticut Town Poly feature class, deleted all polygon attributes with the exception of town number (TOWN_NO) and town name (TOWN). Applied the Union geoprocessing command to overlay the modified town feature class with Subregional Drainage Basins for Clipping to create Connecticut Subregional Basin Town Union feature class, which splits and combines all features from both data sources into one feature class. The ACREAGE and AREA_SQMI attributes in Connecticut Subregional Basin Town Union were recalculated based on the new feature geometry. The total geographic area covered by all polygon features is 7,201.26 square miles, larger than the area covered by Connecticut.
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Internal feature number.
ESRI
Feature geometry.
ESRI
Subregional Drainage Basin Number - This number defines the Subregional drainage basin and is the first 4 digits of the 13-digit drainage basin identification number (BASIN_NO). The first digit corresponds to the Major basin number (MBAS_NO) and the first 2 digits represent the Regional basin number (RBAS_NO). All Subregional basins in the same Major and Regional basin have the same first and first 2 digits, respectively. A Subregional drainage basin number ending in "00" defines the main-stem basin for the corresponding Regional drainage basin. For example, Subregional basin 4300 is the main-stem basin for Regional basin 43. These main-stem Subregional basins are usually named after the corresponding Regional basin.
State of Connecticut, Department of Environmental Protection
Pawcatuck River
Wyassup Brook
Green Fall River
Ashaway River
Shunock River
Wood River
Brushy Brook
Southeast Shoreline
Anguilla Brook
Copps Brook
Williams Brook
Whitford Brook
Haleys Brook
Mystic River
Great Brook
Jordan Brook
Latimer Brook
Oil Mill Brook
Niantic River
Pattagansett River
Bride Brook
Fourmile River
Thames River
Trading Cove Brook
Shewville Brook
Poquetanuck Brook
Oxoboxo Brook
Stony Brook
Hunts Brook
Willimantic River
Edson Brook
Middle River
Furnace Brook
Roaring Brook
Mill Brook
Skungamaug River
Burnap Brook
Hop River
Giffords Brook
Tenmile River
Natchaug River
Bungee Brook
Still River
Bigelow Brook
Stonehouse Brook
Squaw Hollow Brook
Mount Hope River
Fenton River
Sawmill Brook
French River
Mill Brook
Fivemile River
Rocky Brook
Mary Brown Brook
Cady Brook
Whetstone Brook
Moosup River
Quanduck Brook
Snake Meadow Brook
Ekonk Brook
Pachaug River
Great Meadow Brook
Mount Misery Brook
Denison Brook
Myron Kinney Brook
Billings Brook
Quinebaug River
Hamilton Reservoir Brook
Breakneck Brook
Hatchet Brook
Cohasse Brook
Lebanon Brook
English Neighborhood Brook
Mill Brook
Little River
Wappoquia Brook
Mashamoquet Brook
Blackwell Brook
Fry Brook
Mill Brook
Kitt Brook
Cory Brook
Broad Brook
Choate Brook
Shetucket River
Indian Hollow Brook
Beaver Brook
Merrick Brook
Beaver Brook
Little River
Yantic River
Exeter Brook
Bartlett Brook
Sherman Brook
Deep River
Pease Brook
Gardner Brook
Susquetonscut Brook
Connecticut River
Great Brook
Threemile Brook
Freshwater Brook
Podunk River
Folly Brook
Salmon Brook
Hubbard Brook
Cold Brook
Roaring Brook
Goff Brook
Reservoir Brook
Carr Brook
Sumner Brook
Higganum Creek
Mill Creek
Whalebone Creek
Chester Creek
Deep River
Falls River
Lieutenant River
Black Hall River
Stony Brook
Muddy Brook
Scantic River
Watchaug Brook
Gillettes Brook
Gulf Stream
Abbey Brook
Buckhorn Brook
Broad Brook
Ketch Brook
Farmington River
Slocum Brook
Mad River
Still River
Sandy Brook
Morgan Brook
Valley Brook
Hubbard Brook
East Branch Farmington River
Cherry Brook
Nepaug River
Burlington Brook
Roaring Brook
Poland River
Copper Mine Brook
Pequabuck River
Thompson Brook
Nod Brook
Hop Brook
West Branch Salmon Brook
Salmon Brook
Mill Brook
Park River
Bass Brook
Piper Brook
Trout Brook
North Branch Park River
Hockanum River
Charters Brook
Marsh Brook
Tankerhoosen River
South Fork Hockanum River
Mattabesset River
Belcher Brook
Willow Brook
Webster Brook
Sawmill Brook
Allyn Brook
Sawmill Brook
Coginchaug River
Salmon River
Raymond Brook
Judd Brook
Meadow Brook
Pine Brook
Jeremy River
Fawn Brook
Blackledge River
Dickinson Creek
Pine Brook
Moodus River
Eightmile River
Harris Brook
East Branch Eightmile River
Beaver Brook
South Central Shoreline
Oyster River
Patchogue River
Menunketesuck River
Indian River
Chatfield Hollow Brook
Hammonasset River
Neck River
East River
Sluice Creek
West River
Branford River
Farm River
Quinnipiac River
Eightmile River
Tenmile River
Misery Brook
Broad Brook
Sodom Brook
Harbor Brook
Wharton Brook
Muddy River
Willow Brook
Mill River
Sargent River
Wintergreen Brook
West River
Indian River
Wepawaug River
Housatonic River
Sages Ravine Brook
Schenob Brook
Andrus Brook
Konkapot River
Factory Brook
Spruce Swamp Creek
Salmon Creek
Mill Brook
Carse Brook
Furnace Brook
Guinea Brook
Kent Falls Brook
Cobble Brook
Bog Hollow Brook
Macedonia Brook
Womenshenuk Brook
Morrissey Brook
Pond Brook
Deep Brook
Pootatuck River
Kettletown Brook
Halfway River
Eightmile Brook
Means Brook
Farmill River
Pumpkin Ground Brook
Blackberry River
Whiting River
Hollenbeck River
Brown Brook
Wangum Lake Brook
Tenmile River
Indian Lake Creek
Mill Brook
Webatuck Creek
Deuel Hollow Brook
Mill River
Swamp River
Lake Candlewood
Sawmill Brook
Ball Pond Brook
West Aspetuck River
Merryall Brook
East Aspetuck River
Still River
Miry Brook
Boggs Pond Brook
Padanaram Brook
Sympaug Brook
East Swamp Brook
Limekiln Brook
Shepaug River
Marshepaug River
West Branch Shepaug River
West Branch Bantam River
Butternut Brook
Bantam River
Jacks Brook
Pomperaug River
East Spring Brook
Nonewaug River
Sprain Brook
Weekeepeemee River
Hesseky Brook
Transylvania Brook
Naugatuck River
Hall Meadow Brook
Hart Brook
Nickel Mine Brook
West Branch Naugatuck River
East Branch Naugatuck River
Spruce Brook
Rock Brook
Leadmine Brook
Northfield Brook
Branch Brook
Hancock Brook
Steele Brook
Beaver Pond Brook
Mad River
Fulling Mill Brook
Hop Brook
Long Meadow Pond Brook
Beacon Hill Brook
Bladens River
Little River
Southwest Shoreline
Lewis Gut
Bruce Brook
Yellow Mill Channel
Booth Hill Brook
Pequonnock River
Ash Creek
Cricker Brook
Mill River
Sasco Brook
Saugatuck River
Little River
Aspetuck River
West Branch Saugatuck River
Norwalk River
Comstock Brook
Silvermine River
Fivemile River
Darien River
Noroton River
Mill River
Rippowam River
East Branch Mianus River
Mianus River
Greenwich Creek
Horseneck Brook
East Branch Byram River
Byram River
Blind Brook
Hudson River
Croton River
Quaker Brook
Corner Pond Brook
East Branch Croton River
Titicus River
Waccabuc River
Subregional Drainage Basin Name - Text values that correspond to numeric SBAS_NO attribute values. SUBREGION is the English language equivalent of (decodes) the SBAS_NO field.
State of Connecticut, Department of Environmental Protection
Regional Drainage Basin Number - This number defines the Regional drainage basin and is the first 2 digits of the 13-digit drainage basin identification number (BASIN_NO). The first digit corresponds to the Major basin number (MBAS_NO). All Regional basins in the same Major basin have the same first digit. A Regional drainage basin number ending in "0" defines the greater main-stem basin for the corresponding Major drainage basin. For example, Regional basin 40 is the main-stem basin for Major basin 4. These main-stem Regional basins are usually named after the corresponding Major basin.
State of Connecticut, Department of Environmental Protection
Pawcatuck Main Stem
Wood
Southeast Shoreline
Southeast Eastern Complex
Southeast Western Complex
Thames Main Stem
Willimantic
Natchaug
French
Fivemile
Moosup
Pachaug
Quinebaug
Shetucket
Yantic
Connecticut Main Stem
Stony Brook
Scantic
Farmington
Park
Hockanum
Mattabesset
Salmon
Eightmile
South Central Shoreline
South Central Eastern Complex
Quinnipiac
South Central Western Complex
Housatonic Main Stem
Blackberry
Hollenbeck
Tenmile
Candlewood
Aspetuck
Still
Shepaug
Pomperaug
Naugatuck
Southwest Shoreline
Southwest Eastern
Saugatuck
Norwalk
Southwest Western Complex
Hudson Main Stem
Croton
Regional Drainage Basin Name - Text values that correspond to numeric RBAS_NO attribute values. REGIONAL is the English language equivalent of (decodes) the RBAS_NO field.
State of Connecticut, Department of Environmental Protection
Major Drainage Basin Number - This number defines the major drainage basin and is the first digit of the 13-digit drainage basin identification number (BASIN_NO). There are 8 Major basins.
State of Connecticut, Department of Environmental Protection
Pawcatuck
Southeast Coast
Thames
Connecticut
South Central Coast
Housatonic
Southwest Coast
Hudson
Major Drainage Basin Name - Text values that correspond to numeric MBAS_NO attribute values. MAJOR is the English language equivalent of (decodes) the MBAS_NO field.
State of Connecticut, Department of Environmental Protection
Town Number - ID number for the Connecticut Town (municipality), based on the Town Codes issued by the State of Connecticut, Office of the State Controller, which range from 1 to 169. Polygon features with Connecticut Town number values of zero (0) are basin features that do not overlap a Connecticut town and are either located in Long Island Sound, Massachusetts, New York, or Rhode Island.
State of Connecticut, Office of the State Controller
Town Name - Text values that correspond to numeric TOWN_NO attribute values. TOWN is the English language equivalent of (decodes) the TOWN_NO field. Polygon features with Connecticut Town name values that are null or empty are basin features that do not overlap a Connecticut town and are either located in Long Island Sound, Massachusetts, New York, or Rhode Island.
State of Connecticut, Office of the State Controller
Calculated area of polygon feature in acres. Note, ACREAGE values are not automatically updated after modifying feature geometry (shape). Values must be recalculated after features are edited, simplified, generalized, clipped, dissolved, etc.
State of Connecticut, Department of Environmental Protection
Calculated area of polygon feature in square miles. Note, AREA_SQMI values are not automatically updated after modifying feature geometry (shape). Values must be recalculated after features are edited, simplified, generalized, clipped, dissolved, etc.
State of Connecticut, Department of Environmental Protection
Information encoded for drainage basin polygon features generally includes drainage basin number and name, town number and name, and feature size. The SBAS_NO uniquely identifes subreginal drainage basins and uniquely identifies each polygon feature. It represents the first 4 digits of the 13 digit BASIN_NO. The drainage basin numbering system is hierarchical. Use the MBAS_NO and RBAS_NO attributes to identify the major and regional drainage basin for each subregional drainage basin feature. The TOWN_NO identifies the Connecticut Town the basin feature is located in. Typically basins are located in more than one town and a town will include more than one basin so there is a polygon feature for each subregional basin - town occurence. Polygon features with Connecticut Town number values of zero (0) are basin features that do not overlap a Connecticut town and are either located in Long Island Sound, Massachusetts, New York, or Rhode Island. Use the AREA_SQMI and ACREAGE attributes to determine drainage basin - town polygon feature size. These values reflect the area of the respective polygon feature. They do not reflect the cumulative (upstream) drainage area for each basin. Note, ACREAGE and AREA_SQMI values are not automatically updated after modifying feature geometry (shape). These values must be recalculated after features are edited, simplified, generalized, clipped, dissolved, etc.
Basin Numbers: 4 = Major drainage basin number, MBAS_NO (column 1) 43 = Regional drainage basin number, RBAS_NO (columns 1-2) 4302 = Subregional drainage basin number, SBAS_NO (columns 1-4) 4302-04 = Local drainage basin number, LBAS_NO (columns 1-7) 4302-04-1-R12 = Basin drainage identification number, BASIN_NO (columns 1-13) Stream Order (column 9): 4304-00-1 = Stream order value of 1 represents a headwater basin. 4304-00-2 = Stream order value > 1 denotes the complexity of the drainage basin morphology. Mapping Status Element (column 10): 4302-00-2- = Ending with minus sign (-) denotes detail mapping at 1:24,000 scale for entire basin. 4302-00-2+ = Ending with plus sign (+) denotes detailed mapping not performed at 1:24,000 scale for the entire drainage basin. The Stream Order value will not reflect the complexity of the drainage basin morphology. 4302-00-1* = Ending with asterisk sign (*) denotes a headwater basin containing a delineated impoundment into which a delineated drainage basin outlets. Reach-Impoundment Identifier (column11) and Number (column 12-13): 4302-00-1-L1 = The value for the Reach-Impoundment Identifier for an impounment basin is L (for lake). It is followed by the Reach-Impoundment Number (1). 4302-04-1-R12 = The value for the Reach-Impoundment Identifier for a stream reach basin is R (for reach). It is followed the Reach-Impoundment Number (12).
Connecticut Town numbers, based on the Town Codes issued by the State of Connecticut, range from 1 to 169 in the following order: Andover (1), Ansonia (2), Ashford (3), Avon (4), Barkhamsted (5), Beacon Falls (6), Berlin (7), Bethany (8), Bethel (9), Bethlehem (10), Bloomfield (11), Bolton (12), Bozrah (13), Branford (14), Bridgeport (15), Bridgewater (16), Bristol (17), Brookfield (18), Brooklyn (19), Burlington (20), Canaan (21), Canterbury (22), Canton (23), Chaplin (24), Cheshire (25), Chester (26), Clinton (27), Colchester (28), Colebrook (29), Columbia (30), Cornwall (31), Coventry (32), Cromwell (33), Danbury (34), Darien (35), Deep River (36), Derby (37), Durham (38), Eastford (39), East Granby (40), East Haddam (41), East Hampton (42), East Hartford (43), East Haven (44), East Lyme (45), Easton (46), East Windsor (47), Ellington (48), Enfield (49), Essex (50), Fairfield (51), Farmington (52), Franklin (53), Glastonbury (54), Goshen (55), Granby (56), Greenwich (57), Griswold (58), Groton (59), Guilford (60), Haddam (61), Hamden (62), Hampton (63), Hartford (64), Hartland (65), Harwinton (66), Hebron (67), Kent (68), Killingly (69), Killingworth (70), Lebanon (71), Ledyard (72), Lisbon (73), Litchfield (74), Lyme (75), Madison (76), Manchester (77), Mansfield (78), Marlborough (79), Meriden (80), Middlebury (81), Middlefield (82), Middletown (83), Milford (84), Monroe (85), Montville (86), Morris (87), Naugatuck (88), New Britain (89), New Canaan (90), New Fairfield (91), New Hartford (92), New Haven (93), Newington (94), New London (95), New Milford (96), Newtown (97), Norfolk (98), North Branford (99), North Canaan (100), North Haven (101), North Stonington (102), Norwalk (103), Norwich (104), Old Lyme (105), Old Saybrook (106), Orange (107), Oxford (108), Plainfield (109), Plainville (110), Plymouth (111), Pomfret (112), Portland (113), Preston (114), Prospect (115), Putnam (116), Redding (117), Ridgefield (118), Rocky Hill (119), Roxbury (120), Salem (121), Salisbury (122), Scotland (123), Seymour (124), Sharon (125), Shelton (126), Sherman (127), Simsbury (128), Somers (129), Southbury (130), Southington (131), South Windsor (132), Sprague (133), Stafford (134), Stamford (135), Sterling (136), Stonington (137), Stratford (138), Suffield (139), Thomaston (140), Thompson (141), Tolland (142), Torrington (143), Trumbull (144), Union (145), Vernon (146), Voluntown (147), Wallingford (148), Warren (149), Washington (150), Waterbury (151), Waterford (152), Watertown (153), Westbrook (154), West Hartford (155), West Haven (156), Weston (157), Westport (158), Wethersfield (159), Willington (160), Wilton (161), Winchester (162), Windham (163), Windsor (164), Windsor Locks (165), Wolcott (166), Woodbridge (167), Woodbury (168), and Woodstock (169).
79 Elm Street
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79 Elm Street