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This is a Non-Federal dataset covered by different Terms of Use than Data.gov.

Coastal Boundary

Metadata Updated: February 12, 2025

The Coastal Boundary layer is a 1:24,000-scale, polygon feature-based layer of the legal mylar-based maps adopted by the Commissioner of the Department of Environmental Protection (DEP) (i.e., maps were adopted on a town by town basis) showing the extent of lands and coastal waters as defined by Connecticut General Statute (C.G.S.) 22a-93(5)) within Connecticut's coastal area (defined by C.G.S. 22a-94(c)). The coastal boundary is a hybrid of the original 1:24,000 version maps prepared by DEP consistent with C.G.S. 22a-94(d) (Coastal Area) and the revised boundary mapping undertaken by twenty-two coastal towns prepared pursuant to C.G.S. 22a-94(f). This layer therefore does not replace the legal maps and may not be used for legal determinations. The Coastal Boundary layer includes a single polygon feature that represents the coastal boundary. No other features are included in this layer. Data is compiled at 1:24,000 scale. Attribute information is comprised of an Av_Legend attribute and a CoastB_Flg attribute to denote the coastal boundary. Other attributes include automatically calculated Shape_Length and Shape_Area fields. This data is not updated. Any regulated activity conducted within the coastal boundary by a municipal agency (i.e., plans of development, zoning regulations, municipal coastal programs and coastal site plan review (i.e., site plans submitted to zoning commission, subdivision or resubdivision plans submitted to planning commission, application for special permit or exception to the zoning or planning commissions or zoning board of appeals, variance submitted to zoning board of appeals and a referral of a municipal project)) must be conducted in a manner consistent with the requirements of the Connecticut Coastal Management Act (CMA; C.G.S. 22a-90 to 22a-113). As the Coastal Boundary is a hybrid of the Coastal Area, all state and federal agency activities must be consistent with the requirements of the CMA. As defined in C.G.S. 22a-94(b) the coastal boundary is a "continuous line delineated on the landward side by the interior contour elevation of the one hundred year frequency coastal flood zone, as defined and determined by the National Flood Insurance Act, as amended (USC 42 Section 4101, P.L. 93-234), or a one thousand foot linear setback measured from the mean high water mark in coastal waters, or a one thousand foot linear setback measured from the inland boundary of tidal wetlands mapped under section 22a-20, whichever is farthest inland; and shall be delineated on the seaward side by the seaward extent of the jurisdiction of the state." The original boundary maps were created in 1979 on stable mylar overlay using the 1:24,000-scale US Geological Survey topographic quadrangle maps (mylar film format). The source for tidal wetland maps were the legal 1:24,000 maps (mylar format) adopted by the Commissioner of DEP and transformed to 1:24,000 mylar-scale maps by the Office of Policy and Management (OPM) using an accurate pantograph. OPM similarly converted FEMA's flood insurance maps (various scales) to a 1:24,000 mylar overlay. The inland extent of coastal waters was plotted on 1:24,000 USGS topographic maps following the procedures and sources described in The Boundary Between Saltwater and Freshwater in Connecticut, December 1978 prepared by the State of Connecticut, Department of Environmental Protection, Coastal Area Management Program. The following twenty-two towns have adopted municipal coastal boundaries: Chester, Clinton, Darien, Deep River, East Haven, Essex, Fairfield, Greenwich, Groton, Guilford, Hamden, Ledyard, Madison, Milford, New Haven, New London, North Haven, Norwalk, Old Lyme, Old Saybrook, Stamford and Waterford. The coastal boundary maps for these towns may be at different scales than the original DEP draft maps and may contain minor adjustments to the boundary as permitted in C.G.S. 22a-94(f).

Access & Use Information

Public: This dataset is intended for public access and use. Non-Federal: This dataset is covered by different Terms of Use than Data.gov. License: Creative Commons CCZero

Downloads & Resources

Dates

Metadata Created Date September 2, 2022
Metadata Updated Date February 12, 2025

Metadata Source

Harvested from Connecticut Data.json

Additional Metadata

Resource Type Dataset
Metadata Created Date September 2, 2022
Metadata Updated Date February 12, 2025
Publisher Department of Energy & Environmental Protection
Maintainer
Identifier https://www.arcgis.com/home/item.html?id=b5cdf26c7449400caa33b5ef58e4c086&sublayer=0
Data First Published 2018-12-21
Data Last Modified 2018-12-21
Category geospatial
Public Access Level public
Metadata Context https://project-open-data.cio.gov/v1.1/schema/catalog.jsonld
Metadata Catalog ID https://data.ct.gov/data.json
Schema Version https://project-open-data.cio.gov/v1.1/schema
Catalog Describedby https://project-open-data.cio.gov/v1.1/schema/catalog.json
Harvest Object Id 91231ed3-e0fb-49d1-b1a8-9aafc200ad73
Harvest Source Id 36c82f29-4f54-495e-a878-2c07320bf10c
Harvest Source Title Connecticut Data.json
Homepage URL https://geodata.ct.gov/datasets/CTDEEP::coastal-boundary
License https://creativecommons.org/publicdomain/zero/1.0
Metadata Type geospatial
Old Spatial -73.6595,40.9505,-71.8259,41.5402
Source Datajson Identifier True
Source Hash a2709a08cfc4e46718e9bf896d5868c2d54017813fcd0c383bbc990e6fc73a7a
Source Schema Version 1.1
Spatial {"type": "Polygon", "coordinates": -73.6595, 40.9505, -73.6595, 41.5402, -71.8259, 41.5402, -71.8259, 40.9505, -73.6595, 40.9505}

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