Description: This dataset consists of 2-dimensional roof outlines ("roofprints") for all buildings larger than 150 square feet, as interpreted by a contractor (Rolta) for the whole area of the Commonwealth using DigitalGlobe ortho images obtained in 2011 and 2012, supplemented with LiDAR (Light Detection And Ranging) data collected from 2002 to 2011 for the eastern half of the state. The roofprints as delivered were enhanced by MassGIS using Normalized Digital Surface Models (NDSMs) derived from the same LiDAR data. Other layers were used, including the Level 3 Parcels, to aid in review, especially where LiDAR data were not available.This feature class is being updated using ortho imagery captured in 2013, 2014, 2015 and 2016. The newer imagery allows MassGIS staff to remove, modify and add structures to keep up with more current ground conditions. Structures from the original compilation that are removed are stored in an "archive" feature class for edit tracking and historical purposes.Last updated on 10/2/2017.In ArcSDE the layer is named STRUCTURES_POLY.
CoastalStructureType
(
type: esriFieldTypeString, alias: Coastal Structure Type, length: 50
, Coded Values:
[Jetty: Man-made piles of boulders or concrete that are built on either side of a coastal inlet]
, [Groins: A groin is a shoreline structure that is perpendicular to the beach.]
, [Revetment: Structures built of concrete, wood, steel or boulders that run parallel to the beach at the land/water interface]
)
Description: This layer is a combination of individual town layers that went through low-lying road analyses from 2021-2023. Risk, inundation probability, criticality, and mean high water elevations were evaluated to enable participating towns to prioritize areas for transportation design improvements.