This raster dataset is the result of a subtraction of the classification
of raster datasets bhd2030us and bhd2000us. Both are produced using the
SERGoM v3 model, they depict housing density for the coterminous US in
2030 and 2000, resp., and are based on 2000 US Census Bureau block (SF1)
datasets. (The classication of the subtraction is shown below.) A
raster layer that portrays not-developed (and assumed to be
undevelopable) called CUS_UPP_100 depicts protected/unprotected lands
and Census water polygons. First, Land was removed from blocks (reducing
the area of a block, but not its number of housing units -- assuming
that private housing units must be on private land) that was public
and/or protected in the UNPROTPRIV100 dataset produced by Forest
Inventory and Analysis, North Central Research Station, USDA Forest
Service -- which is based on the second edition (2001) of the Protected
Areas Database, produced by the Conservation Biology Institute. Second,
locations of blocks that are identified as water polygons (rivers,
lakes, reservoirs, marshes -- basically unbuildable areas) in the US
Census Bureau TIGER files were also removed from the blocks. Third,
blocks that had no housing units in them AND were dominated (>25% of
their area) by developed land use were also not allowed to have any
housing density in subsequent years (by removing those cells from the
developable layer). The value of 22, 23, and 24 from the USGS's NLCD
2001 was used, then aggregated by a factor of 4 (from 30 m to 120 m
cells). Locations where >25% comm/ind/trans were found to create
NLCD_COMMIND dataset.
Classification of Housing Density
Value Acres per Unit Name Definition 0-10 scale
0 Private, no units Private, no units No development
risk 0
1 >40 Rural Low
development risk 3
2 10 - 40 Exurban Moderate
development risk 5
3 1.7-10 Suburban High
development risk 8
4 <1.7 Urban Very
high development risk 10