Upper Rio Grande Watershed Building Footprints
Metadata from the RGIS Metadata Repository
Identification Information
- Title Upper Rio Grande Watershed Building Footprints
- Date 2019-09-16
- Date Type Publication
- Cited Responsible Party
-
- Organization Name Shawn Penman , Earth Data Analysis Center, GIT Manager
- Role identify
- Presentation Form vector digital data
- Abstract The LAS data set was originally classified according to 4 classes (ground,
water, bridge overpass, and noise), with the rest of the data being unclassified.
That left some classes to be derived and classified, of which one—the building/
structure class—was considered necessary for this project. In theory, deriving a
building/structure layer is relatively straightforward: the building reflectance
response should be unclassified, single-reflectance response points, whereas the
vegetation, also unclassified, should yield a multiple-reflectance response as the
beam bounces back through the canopy. Following this idea, we created a Digital
Surface Model (DSM) from the single-response, unclassified LAS point cloud. We then
subtracted these DSMs from the Bare Earth DEMs to create a difference image, which
ideally should represent only buildings. Unfortunately, many trees were included in
this “buildings” layer, due possibly to the sparse canopy that is characteristic of
trees found in southwestern forests and possibly to the presence of fairly recent
burn scars that include a number of standing dead trees and snags. In an attempt to
remove the clutter of false positives due to trees, we developed a Normalized
Difference Vegetation Index (NDVI) from the NAIP imagery acquired over the area in
the same year. The NDVI is an image-processing technique that uses the reflective
information found in the red (Red) and near-infrared (NIR) wavelengths to enhance
the “green” vegetative response over other, non-vegetated surface features (Eq. 1).
NDVI = (NIR−Red)/(NIR+Red) [Eq. 1]. This provides a floating-point image of values
from -1 to 1, with numbers above 0 representing increasing vegetative cover. We
further modified the NDVI equation to create an 8-bit image (Eq. 2). NDVImod =
(NDVI+1)*100 [Eq. 2]. This 8-bit image had all positive integer values, where values
above 100 indicated increasing vegetative cover. We used the generated NDVI image,
in particular values above 109, to mask out many of the false anomalies. In
addition, all heights less than 6 feet were masked out, as this was considered a
minimum height for most buildings. We added 1 to values in the resulting image so
that all values, even the zeroes, would be counted. Then values were clumped to
produce an image of individually coded raster polygons. We eliminated all clusters
smaller than 32 square meters (345 square feet) from the clumped image, ran a 3x3
majority filter to remove relict edges, and ran a 3x3 morphological close filter to
remove holes in the raster polygons. We completed the raster processing in ERDAS
IMAGINE and then converted the data set to a polygon layer in ESRI ArcGIS, as is and
without using the ‘simplify polygon’ option. This was cleaned up further using the
simplify buildings module with a minimum spacing of 2 meters. Once this was
completed, the polygon layer was edited using the NAIP imagery and DSM Shaded Relief
imagery as a background by a heads-up digitizing at a 1:3,000 scale (the approximate
base resolution of the LiDAR data). The building/structure layer contained more than
44,612 identified structures.
- Purpose This is a layer showing building footprints within the Upper Rio Grande Watershed. This layer was derived from QL2 LiDAR data
and processed using
semi-automated techniques.
- Data Set Credit Earth Data Analysis Center
- Status Complete
- Point of Contact
-
- Individual Name
- Organization Name Earth Data Analysis Center
- Position Name GIT Specialist
- Role Point of contact
- Voice 505-277-3622 ext. 227
- Facsimile
- Address
-
- Delivery Point 400 University Blvd NE #16
- City Albuquerque
- Administrative Area NM
- Postal Code 87131
- Country US
- Electronic Mail Address spenman@edac.unm.edu
- Maintenance and Update Frequency As needed
- Descriptive Keywords Building footprints, LiDAR, DSM, DEM
- Access Constraints None
- Use Constraints None
- Language English
- Topic Category structure
- Extent
-
- Geographic Bounding Box
-
- West Bound -106.388137164
- East Bound -105.292160176
- North Bound 37.014164902
- South Bound 35.713843327
- Temporal Extent
-
- DateTime 2019-05-16
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Distribution Information
- Distributor
-
- Individual Name
- Organization Name Earth Data Analysis Center
- Position Name Clearinghouse Manager
- Role Point of contact
- Voice 505-277-3622 ext. 230
- Facsimile 505-277-3614
- Address
-
- Delivery Point MSC01 1110
- Delivery Point 1 University of New Mexico
- City Albuquerque
- Administrative Area NM
- Postal Code 87131-0001
- Country USA
- Electronic Mail Address clearinghouse@edac.unm.edu
- Transfer Options
-
- Online Resource ZIP
- Online Resource ESRI Shapefile (shp)
- Online Resource GML
- Online Resource KML
- Online Resource GeoJSON
- Online Resource JSON
- Online Resource Comma Separated Values (csv)
- Online Resource MS Excel format (xls)
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Spatial Reference Information
- Spatial References
-
- Spatial Reference NAD 1983 UTM Zone 13N
-
- Online Reference EPSG:26913
- Indirect Spatial Reference Upper Rio Grande Watershed in New Mexico
- Geometric Object Type GT-polygon composed of chains
- Geometric Object Count 44611
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Data Quality Information
- Logical Consistency Report Not provided
- Completeness Report Not provided
- Lineage
-
- Process Step
-
- Process Description Created DSM and DEM from the LiDAR LAS dataset.
- Process Date 2017-10-16
- Process Time 17:00:00
- Process Contact
-
- Individual Name
- Organization Name Earth Data Analysis Center
- Position Name GIS Specialist/Programmer
- Role Point of contact
- Voice 505-277-3622 ext. 244
- Facsimile
- Address
-
- Delivery Point 400 University Blvd NE #16
- City Albuquerque
- Administrative Area NM
- Postal Code 87131
- Country
- Electronic Mail Address pneville@edac.unm.edu
- Process Step
-
- Process Description Extracted the DEM from the DSM.
- Process Date 2017-10-16
- Process Time 17:00:00
- Process Contact
-
- Individual Name
- Organization Name Earth Data Analysis Center
- Position Name GIS Specialist/Programmer
- Role Point of contact
- Voice 505-277-3622 ext. 244
- Facsimile
- Address
-
- Delivery Point 400 University Blvd NE #16
- City Albuquerque
- Administrative Area NM
- Postal Code 87131
- Country
- Electronic Mail Address pneville@edac.unm.edu
- Process Step
-
- Process Description Using NDVI to remove the fal postitives due to trees and
vegetation.
- Process Date 2018-04-17
- Process Time 17:00:00
- Process Contact
-
- Individual Name
- Organization Name Earth Data Analysis Center
- Position Name GIS Specialist/Programmer
- Role Point of contact
- Voice 505-277-3622 ext. 244
- Facsimile
- Address
-
- Delivery Point 400 University Blvd NE #16
- City Albuquerque
- Administrative Area NM
- Postal Code 87131
- Country
- Electronic Mail Address pneville@edac.unm.edu
- Process Step
-
- Process Description We added 1 to values in the resulting image so that all values, even the
zeroes, would be counted. Then values were clumped to produce an image of
individually coded raster polygons. Majority filter and morphological fliter
were used to remove relict edges and holes in the raster polygons.
- Process Date 2018-04-19
- Process Time 17:00:00
- Process Contact
-
- Individual Name
- Organization Name Earth Data Analysis Center
- Position Name GIS Specialist/Programmer
- Role Point of contact
- Voice 505-277-3622 ext. 244
- Facsimile
- Address
-
- Delivery Point 400 University Blvd NE #16
- City Albuquerque
- Administrative Area NM
- Postal Code 87131
- Country
- Electronic Mail Address pneville@edac.unm.edu
- Process Step
-
- Process Description Raster polygons were converted to vector polygons and further processed
with heads-up digitizing.
- Process Date 2019-01-15
- Process Time 17:00:00
- Process Contact
-
- Individual Name
- Organization Name Earth Data Analysis Center
- Position Name GIS Specialist/Programmer
- Role Point of contact
- Voice 505-277-3622 ext. 244
- Facsimile
- Address
-
- Delivery Point 400 University Blvd NE #16
- City Albuquerque
- Administrative Area NM
- Postal Code 87131
- Country
- Electronic Mail Address pneville@edac.unm.edu
- Process Step
-
- Process Description Final product layer was exported as a shapefile.
- Process Date 2019-05-15
- Process Time 17:00:00
- Process Contact
-
- Individual Name
- Organization Name Earth Data Analysis Center
- Position Name GIS Specialist/Programmer
- Role Point of contact
- Voice 505-277-3622 ext. 244
- Facsimile
- Address
-
- Delivery Point 400 University Blvd NE #16
- City Albuquerque
- Administrative Area NM
- Postal Code 87131
- Country
- Electronic Mail Address pneville@edac.unm.edu
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Metadata Reference Information
- File Identifier ef5dc9d2-1ab4-4458-a059-4e056ef0c054
- Metadata Language English
- Hierarchy Level Dataset
- Date Stamp 2025-07-26
- Metadata Standard Name ISO 19115:2003
- Metadata Standard Version 1.0
- Metadata Contact
-
- Individual Name
- Organization Name Earth Data Analysis Center
- Position Name Clearinghouse Manager
- Role Point of contact
- Voice 505-277-3622 ext. 230
- Facsimile 505-277-3614
- Address
-
- Delivery Point MSC01 1110
- Delivery Point 1 University of New Mexico
- City Albuquerque
- Administrative Area NM
- Postal Code 87131-0001
- Country USA
- Electronic Mail Address clearinghouse@edac.unm.edu
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