PAG protocol for Land Use map updates

1. Obtain County tax assessor’s records
2. Apply lookup table (attached) to convert use codes to preliminary land use categories
3. Override preliminary land use categories using polygons derived from the following twelve ancillary shapefiles, which are updated separately on an annual basis by PAG::
a. Mines—updated based on aerials?
b. Airport
c. Multi-use family
d. ??
e. 

4. Convert to 10 square foot grid cells
5. Use SHRINK in ArcGIS.  This routine identifies gaps and grows the category outward to fill the gap.  It also searches nearest neighbor cells and aggregates when similar cells are encountered.
6. Convert back to polygons.  This is the end of the main protocol.  
7. There is an additional subroutine to update residential density categories as follows:  intersect land use categories with census blocks to identify residential.  If the census identfies as residential then
8. Apply building permits to update the census count on each residential polygon.    Building permit data is also used to override vacant tax codes. Note that PAG uses a 6 month lag on building permits to give time to complete projects.