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  • Important fields for record selection criteria in SIMS-County queries.

SIMS Field Name

Item #

SIMS Table




Code "Y" indicates that a road is carried on the bridge and that the road is linked in the Illinois Roadway Information System.



Code "Y" indicates that a road is carried under the bridge and that the road is linked in the Illinois Roadway Information System.


ISIS Master
ISIS Summary

Field operational status of bridge. e.g., Code "2" indicates weight limit posting in place and code "9" is for bridges not yet built, etc.


ISIS Master
ISIS Summary

Bridges 20.0' or less that carry a road are not subject to the NBIS.


ISIS Master
ISIS Summary

Indicates type of agency responsible for reporting ISIS data to IDOT. e.g., State reported structures = "1", County reported structures = "3".


ISIS Master
ISIS Summary

2-digit ID # for the structural type of a bridge. Code "26" (Low Water Crossing) structures, and certain other types, should normally be excluded in queries since they are not subject to the NBIS.


Tables w/2 or more records per bridge*

Indicates the historical sequence of NBIS inspections, etc., with the most recent coded "1".
MaintRespA & MaintRespB

21A & 21B

ISIS Master
ISIS Summary

Indicates the types of agencies responsible for the maintenance of a structure.


ISIS Master
ISIS Summary

3-digit ID # indicating the county where the agency with primary maintenance responsibility is located.
MunicipalityCodeOn or ...Under


Key Route On or …Under
ISIS Summary

4-digit ID # for the municipality where the road on or under the structure is located. (Not related to bridge maintenance.)


ISIS Master
ISIS Summary

For township bridges, 2-digit ID # for township responsible for bridge maintenance.
* Tables that may have 2 or more records per bridge: Const Reconstruction, Fracture Critical Inspections, Fracture Critical Members, Inspection Appraisals, Key Route On, Key Route Under, Microfilm History, Scour Critical Inspections, Underwater Inspections.
Note: For detailed descriptions of fields refer to the IDOT Structure Information and Procedure Manual.
  • If the Criteria box in the query design for the field "KRLinkOn" is not set to "Y", your query will generate records for any structures that may be in your county carrying railroads, bikepaths, etc., in addition to bridges carrying roads. These structures do not require NBIS inspections.
  • The field "SequenceNbr" will usually be needed in queries that include tables that may have more than one record per structure. For example, in the table "Inspection Appraisals", SequenceNbr is 1 for the most recent inspection, 2 for the inspection previous to "1", 3 for the one previous to "2", etc. The SequenceNbr field in Construction / Reconstruction information employs a slightly different coding scheme. The Original Construction record (code "O") always has SequenceNbr = "0" (zero), Reconstruction (code "R") records are numbered in descending date order from "1" to "50" and minor maintenance (code "M") records are numbered by descending date beginning with "51".
  • Care must be exercised when performing queries referring to multiple tables where some of the records of one are not matched in the other. When the tables are joined in the query, give special attention to proper configuration of the join properties. Example: A query is based on the ISIS Master and Inspection Appraisals tables and it is desired to output data for bridges not yet inspected (i.e. no Inspection Appraisals record exists). Use the following Join Property- "Include ALL records from 'ISIS Master' and only those records from 'Inspection Appraisals' where the joined fields are equal." The link between the tables will be graphically represented by a line with and arrow head pointing to the Inspection Appraisals table box.
  • To simplify querying in SIMS-County, the ISIS Summary State And Local table has been provided. This table contains, in one record per bridge, data from the ISIS Master, Key Route, Construction and other tables including only the most recent inspection and reconstruction information. The one record per structure format simplifies querying by making table joins unnecessary.


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