Dewberry 20250207 vector data Product: Building footprints are used support planning and other State and local uses and were created during the CT Statewide GIS Services lidar project. Building footprints are reviewed against lidar intensity imagery to verify completeness of capture. Geographic Extent: CT Statewide covering approximately 5,241 square miles. Dataset Description: CT Statewide GIS Services Lidar project called for the Planning, Acquisition, processing and derivative products of lidar data to be collected at a nominal pulse spacing (NPS) of 0.35 meter; coastal areas were acquired to achieve >=20 ppsm, and all other areas were acquired to achieve >=14 ppsm. Project specifications are based on the U.S. Geological Survey National Geospatial Program Base Lidar Specification, Version 2023 rev. A. The data was developed based on a horizontal datum/projection of NAD83 (2011), State Plane Connecticut, U.S. Survey Feet and vertical datum of NAVD88 (GEOID18), U.S. Survey Feet. Lidar data was delivered as processed Classified LAS 1.4 files, formatted to 23,381 individual 2,500 ft x 2,500 ft tiles, as tiled Intensity Imagery, and as tiled bare earth DEMs; all tiled to the same 2,500 ft x 2,500 ft schema. Maximium Surface Height Raster and Swath Separation Image tiles 025645_se, 080655_ne, 085655_ne, 085655_nw, 090655_nw, 110660_se, and 135665_se do not exist in the deliverables due to all of the points in the cooresponding LAS tiles being flagged as withheld. LAS file 110660_se is all water and contains no lidar returns, this file does not exist in the deliverables. Ground Conditions: Lidar was collected in Spring 2023, while no snow was on the ground and rivers were at or below normal levels. In order to post process the lidar data to meet task order specifications and meet ASPRS vertical accuracy guidelines, Dewberry established a total of 38 ground control points that were used to calibrate the lidar to known ground locations established throughout the CT Statewide GIS Services project area. An additional 247 independent accuracy checkpoints, 145 in Bare Earth and Urban landcovers (145 NVA points), 102 in Tall Grass and Brushland/Low Trees categories (102 VVA points), were used to assess the vertical accuracy of the data. These checkpoints were not used to calibrate or post process the data. 2D building footprints are a digitial representation of a building's perimeter on a map. They are used for urban planning, land use analysis, risk assessment, and other mapping products. Building Footprint File Type = GDB 20230322 20230507 ground condition Complete None planned -73.753399 -71.774215 42.061450 40.973152 727500.000094 1264999.999895 947499.999991 552499.999967 None Model Building footprint Elevation Data Lidar None Connecticut No restrictions apply to these data. None. However, users should be aware that temporal changes may have occurred since this dataset was collected and that some parts of these data may no longer represent actual surface conditions. Users should not use these data for critical applications without a full awareness of its limitations. Data covers the entire area specified for this project. Building footprints were collected on both commerical and residential buildings. All buildings greater than 100 square feet were collected. Building footprints were created from the Lidar point cloud and thus may be affected by lidar point density, laser shadowing due to both vegetation and man made features, surface reflectivity, and irregularity of points. All files are inspected to ensure that they conform to the specified file naming conventions, all files load in their correct geographic position, all files conform to the project specifications for file standard and content. Dewberry has produced 2D building footprints from lidar for the State of Connecticut. These footprints were derived from Lidar using ArcGIS Pro and TerraScan software packages, and Dewberry's proprietary tools. Step 1: Classify Buildings: Using ArcGIS Pro or Terrascan the software uses designated parameters to reclassify non-ground points to class 6 Buildings. Among the criteria are minimum rooftop height, minimum area, and a maximum height above roof. Step 2: Aggregate Points: Using Dewberry's Automated Tool Suite, the class 6 Lidar points are used to create an aggregated polygon. Step 3: Regularize: Using ArcGIS Pro and Dewberry's Automated Tool Suite, the aggregated polygons are regularized to create right angles and straight lines. Step 4: Eliminate Parts: Using ArcGIS Pro, interior holes within the building footprints are removed if less than 65 square feet. In between each of the main four steps, the building data is reviewed by our independent quality team before it enters production as well as at the end of the building process. 20240505 Vector Lambert Conformal Conic (State Plane Connecticut FIPS 6434) 41.2 41.86666666666667 -72.75 40.83333333333334 999999.999996 499999.999998 coordinate pair 0.01 0.01 U.S. Survey Feet North American Datum of 1983 (2011) Geodetic Reference System 80 6378137 298.257222101 North American Vertical Datum of 1988, Geoid 18 0.01 U.S. Survey Feet Explicit elevation coordinate included with horizontal coordinates 20250207 20250207 Dewberry mailing and physical

1000 N Ashley Drive, suite 801

Tampa FL 33602 USA (813)225-1325 FGDC Content Standard for Digital Geospatial Metadata FGDC-STD-001-1998 None. None. None. Unclassified. None. None. None.