The parcels are, of course, horizontal only datum.
from the .prj
PROJCS["NAD_1983_StatePlane_New_Jersey_FIPS_2900_Feet",
GEOGCS["GCS_North_American_1983",
DATUM["D_North_American_1983",SPHEROID["GRS_1980",6378137.0,298.257222101]],
PRIMEM["Greenwich",0.0],UNIT["Degree",0.0174532925199433]],
PROJE
You may want to join the proj list.
Your parcel maps are in EPSG (ESRI, really) 102711, which is:
http://spatialreference.org/ref/esri/102711/
This is a horizontal-only datum. I have only encountered horizontal
data in parcel maps (Mass, not NJ). Do you have any heights presented
with this?
