August 1996
This datalayer represents Offshore city and town boundaries for Massachusetts.

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OVERVIEW

This datalayer represents Offshore city and town boundaries for Massachusetts. The data are derived from 1:80,000 NOAA Charts and 1:24,000 USGS quadrangle maps of various dates. The coastline is the same as in the TOWNS_POLY and OUTLINE _POLY layers (1:100,000 USGS).

In ArcSDE are two layers - OFFSH80K_POLY and OFFSH80K_ARC.

ATTRIBUTES

The OFFSH80K_POLY attribute table contains the following items:

SEA	0 and 1
TOWN_ID	Unique municipal identifier (from 1-351 Town ID List)

The OFFSH80K_ARC attribute table contains the following items:

SOURCE	Source of arc and person digitizing. Arc source is either NOAA 1:80,000 charts or USGS 1:24,000 topographic quadrangle maps.
TYPE	Numeric code for source

Codes are as follows:

Type	Source
0	UNKNOWN
1	V. ANTIL, DFWELE, NOAA CHARTS
2	V. ANTIL, DFWELE, USGS 1:24,000 TOPO MAPS
3	D. WEAVER, MassGIS, 1:24,000 USGS TOPO MAPS
4	N. MACGAFFEY, CZM, USGS 1:24,000 TOPO MAPS
5	MISC SOURCES

 

MAINTENANCE

MassGIS is maintaining the datalayer. No updates are planned. For more spatially-accurate coastline data see the Towns from Survey Points layer.

 

Last Updated 9/30/2008