Coordinate Transformation Issues

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We are a GIS department using ArcDesktop and SDE 10.3. We are receiving service requests through a 3rd party web application (seeclickfix) that records the service request in WGS 84 lat/long. The application then transforms the coordinates into TN State Plane using the method described below.

Here is the projection data that postgis (our database) uses to do the X/Y conversion.

Standard NAD83 / Tennessee (ftUS) that comes loaded with PostGIS 2.1.

SRID 2274

PROJCS["NAD83 / Tennessee (ftUS)",GEOGCS["NAD83",DATUM["North_American_Datum_1983",SPHEROID["GRS 1980",6378137,298.257222101,AUTHORITY["EPSG","7019"]],TOWGS84[0,0,0,0,0,0,0],AUTHORITY["EPSG","6269"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4269"]],UNIT["US survey foot",0.3048006096012192,AUTHORITY["EPSG","9003"]],PROJECTION["Lambert_Conformal_Conic_2SP"],PARAMETER["standard_parallel_1",36.41666666666666],PARAMETER["standard_parallel_2",35.25],PARAMETER["latitude_of_origin",34.33333333333334],PARAMETER["central_meridian",-86],PARAMETER["false_easting",1968500],PARAMETER["false_northing",0],AUTHORITY["EPSG","2274"],AXIS["X",EAST],AXIS["Y",NORTH]]

+proj=lcc +lat_1=36.41666666666666 +lat_2=35.25 +lat_0=34.33333333333334 +lon_0=-86 +x_0=600000 +y_0=0 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=us-ft +no_defs

When the points hit our system they are consistently off by a few meters. Ie if a service request comes in as 123 main, it gets the lat/long and converts, when it comes back to us in the GIS as a point, it is now slightly shifted to a neighboring house. Are we missing a parameter in the transformation? What could be causing this issue?



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